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CHAPTER 1 GENERAL Chapter 1 General
ARTICLE 90 INTRODUCTION
90.1 Purpose: Add- (A) This Code is not
intended as a design specification or an
instruction manual for untrained persons.
90.8 (B) Number of Circuits in Enclosures.
Limiting the number of circuits in a single
enclosure minimizes the effects from a short
circuit or ground fault.
ARTICLE 100 DEFINITIONS ARTICLE 100 Definitions
Adjustable Speed Drive. New definitions.
Adjustable Speed Drive System. New
definitions.
Associated Apparatus [as applied to Hazardous
(Classified) Locations]. New definition.
Associated Nonincendive Field Wiring [as applied
to Hazardous (Classified) Locations]. New
definition.
Cable Routing Assemblies. A single channel or
connected multiple channels, as well as
associated fittings, forming a structural system
that is used to support and route communications
wires and cables associated with information
technology and communications equipment, Class
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2, Class 3, and Type PLTC cables, and power-
limited fire alarm cables in plenums, risers, and
general-purpose applications. (CMP-16)
Battery System. New definitions.
Cable Rating Assembly. New definitions.
Charge Controller. New definitions.
Combustible Dust [as applied to Hazardous
(Classified) Locations]. New definition.
Combustible Gas Detection System [as applied to
Hazardous (Classified) Locations]. New definition.
Communications Raceway. New definitions.
Control Circuit. New definitions.
Control Drawing (Classified) Locations]. New
definition.
Coordination (Selective). Localization of an
overcurrent
condition to restrict outages to the circuit or
equipment
affected, accomplished by the choice
selection and installation of overcurrent
protective devices and their ratings or
settings, for the full range of available
overcurrents, from overload to the
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maximum available fault current, and for the
full range of overcurrent protective device
opening time associated with those
overcurrents.
Device. A unit of an electrical system, other
than a conductor, that carries or controls
electric energy as its principal function.
Dust-IgnitionProof [as applied to Hazardous
(Classified) Locations]. New definition.
Dusttight [as applied to Hazardous (Classified)
Locations]. New definition.
Effective Ground-Fault Current Path. New
definitions.
Electric-Discharge Lighting. New definitions.
Electronically Actuated Fuse. New
definitions.
Ground-Fault Current Path. New definitions.
Grounding Conductor, Equipment (EGC).
The conductive path(s) that provides a
ground-fault current path and connects
installed to connect normally non–current-
carrying metal parts of equipment together
and to the system grounded conductor or to
the grounding electrode conductor, or both.
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Informational Note No. 1: It is recognized
that the equipment grounding conductor
also performs bonding.
Informational Note No. 2: See 250.118 for a
list of acceptable equipment grounding
conductors.
Hermetic Refrigerant Motor-Compressor.
New definitions.
Hermatically Sealed [as applied to Hazardous
(Classified) Locations]. New definition.
Industrial Control Panel. New definitions.
Information Technology Equipment (ITE) New
definition.
Innerduct. New definition.
Intrinsically Safe Apparatus. New definition.
Lighting Track (Track Lighting). New
definitions.
Nonincendive Circuit [as applied to Hazardous
(Classified) Locations]. New definition.
Nonincendive Component [as applied to
Hazardous (Classified) Locations]. New definition.
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Nonincendive Equipment [as applied to
Hazardous (Classified) Locations]. New definition.
Nonincendive Field Wiring [as applied to
Hazardous (Classified) Locations]. New definition.
Nonincendive Field Wiring Apparatus [as applied
to Hazardous (Classified) Locations]. New
definition.
Photovoltaic (PV) System. New definitions.
Retrofit Kit. New definitions.
Separately Derived System. A premises
wiring system whose power is derived from a
source of electric energy or equipment other
than a service. Such systems have no direct
connection from circuit conductors of one
system to circuit conductors of another
system, other than connections through the
earth, metal enclosures, metallic raceways,
or equipment grounding conductors.
Substation. New definitions.
Switchgear. New definitions.
ARTICLE 110 Requirements for Electrical
Installations
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110.9 Interrupting Rating. Equipment
intended to interrupt current at fault levels
shall have an interrupting rating not less
than the at nominal circuit voltage and
sufficient for the current that is available at
the line terminals of the equipment.
Equipment intended to interrupt current at
other than fault levels shall have an
interrupting rating at nominal circuit voltage
not less than sufficient for the current that
must be interrupted.
110.9 Interrupting Rating. Equipment intended to
interrupt current at fault levels shall have an
interrupting rating the at nominal circuit voltage
at least equal to sufficient for the current that is
available at the line terminals of the equipment.
Equipment intended to interrupt current at other
than fault levels shall have an interrupting rating
at nominal circuit voltage at least equal to
sufficient for the current that must be
interrupted.
110.14 Electrical Connections.
(D) Installation. New section.
110.16 Arc-Flash Hazard Warning. Electrical
equipment,
such as switchboards, switchgear,
panelboards, industrial control panels, meter
socket enclosures, and motor control
centers, that are in other than dwelling units,
and are likely to require examination,
adjustment, servicing, or maintenance while
energized shall be field or factory marked to
warn qualified persons of potential electric
arc flash hazards. The marking shall meet the
requirements in 110.21(B) and shall be
located so as to be clearly visible to qualified
110.16 Arc-Flash Hazard Warning.
(A) General. Electrical equipment, such as
switchboards, switchgear, panelboards, industrial
control panels, meter socket enclosures, and
motor control centers, that are in other than
dwelling units, and are likely to require
examination, adjustment, servicing, or
maintenance while energized shall be field or
factory marked to warn qualified persons of
potential electric arc flash hazards. The marking
shall meet the requirements in 110.21(B) and
shall be located so as to be clearly visible to
qualified persons before examination,
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persons before examination, adjustment,
servicing, or maintenance of the equipment.
adjustment, servicing, or maintenance of the
equipment.
(B) Service Equipment. New subsection.
110.21 Marking.
(A) Manufacturer’s Markings. The
manufacturer’s name, trademark, or other
descriptive marking by which the
organization responsible for the product can
be identified shall be placed on all electrical
equipment. Other markings that indicate
voltage, current, wattage, or other ratings
shall be provided as specified elsewhere in
this Code. The marking or label shall be of
sufficient durability to withstand the
environment involved.
(B) Field-Applied Hazard Marking. Where
caution warning, or danger signs or labels
are required by this Code, the labels shall
meet the following requirements:
(1) The marking shall adequately warn of the
hazard using effective words and/or colors
and/or symbols.
Informational Note: ANSI Z535.4-2011,
Product Safety Signs and Labels, provides
guidelines for suitable font sizes, words,
colors, symbols, and location requirements
for labels.
110.21 Marking.
(A) Manufacturer’s Markings. The manufacturer’s
name, trademark, or other descriptive marking by
which the organization responsible for the
product can be identified shall be placed on all
electrical equipment. Other markings that
indicate voltage, current, wattage, or other
ratings shall be provided as specified elsewhere in
this Code. The marking or label shall be of
sufficient durability to withstand the environment
involved.
(B) Field-Applied Hazard Marking. Where caution
warning, or danger signs or labels are required by
this Code, the labels shall meet the following
requirements:
(1) The marking shall adequately warn of the
hazard using effective words and/or colors and/or
symbols.
Informational Note: ANSI Z535.4-2011, Product
Safety Signs and Labels, provides guidelines for
suitable font sizes, words, colors, symbols, and
location requirements for labels.
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(2) The label shall be permanently affixed to
the equipment or wiring method and shall
not be hand written.
Exception to (2): Portions of labels or
markings that are variable, or that could be
subject to changes, shall be permitted to be
hand written and shall be legible.
(3) The label shall be of sufficient durability
to withstand the environment involved.
Informational Note: ANSI Z535.4-2011,
Product Safety Signs and Labels, provides
guidelines for the design and durability of
safety signs and labels for application to
electrical equipment.
(2) The label shall be permanently affixed to the
equipment or wiring method and shall not be
hand written.
Exception to (2): Portions of labels or markings
that are variable, or that could be subject to
changes, shall be permitted to be hand written
and shall be legible.
(3) The label shall be of sufficient durability to
withstand the environment involved.
Informational Note: ANSI Z535.4-2011, Product
Safety Signs and Labels, provides guidelines for
the design and durability of safety signs and labels
for application to electrical equipment.
110.25. New section.
110.26 Spaces About Electrical Equipment:
(C)(3) Personnel Doors. Where equipment
rated 1200 800 A or more that contains
overcurrent devices, switching devices, or
control devices is installed and there is a
personnel door(s) intended for entrance to
and egress from the working space less than
7.6 m (25 ft) from the nearest edge of the
working space, the door(s) shall open in the
direction of egress and be equipped with
listed panic hardware panic bars, pressure
110.26 Spaces About Electrical Equipment.
(A) Working Space. Working space for equipment
operating at 600 1000 volts, nominal, or less to
ground and likely to require examination,
adjustment, servicing, or maintenance while
energized shall comply with the dimensions of
110.26(A)(1), (A)(2), and (A)(3), and (A)(4) or as
required or permitted elsewhere in this Code.
(3) Height of Working Space. Add-
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plates, or other devices that are normally
latched but open under simple pressure.
(E)(2) Outdoor. Outdoor installations shall
comply with 110.26(E)(2)(a) and (b).
(a) Installation Requirements: Outdoor
electrical equipment shall be installed in
suitable enclosures and shall be protected
from accidental contact by unauthorized
personnel, or by vehicular traffic, or by
accidental spillage or leakage from piping
systems. The working clearance space shall
include the zone described in 110.26(A). No
architectural appurtenance or other
equipment shall be located in this zone.
(b) Dedicated Equipment Space. The space
equal to the width and depth of the
equipment, and extending from grade to a
height of 1.8 m (6 ft) above the equipment,
shall be dedicated to the electrical
installation. No piping or other equipment
foreign to the electrical installation shall be
located in this zone.
Exception No. 3: On battery systems mounted on
open racks, the top clearance shall comply with
480.10(D).
(4) Limited Access. New section.
(5) Separation from High Voltage Equipment.
New section.
(E)(2) Outdoor. Outdoor installations shall comply
with 110.26(E)(2) (a) and (b) through (c).
(a) Installation Requirements: Outdoor electrical
equipment shall be the following:
(1) Installed in identified enclosures
(2) Protected from accidental contact by
unauthorized personnel or by vehicular traffic.
(3) Protected from accidental spillage or leakage
from piping systems.
(b) Working Space. Outdoor electrical equipment
shall be installed in suitable enclosures and shall
be protected from accidental contact by
unauthorized personnel, or by vehicular traffic, or
by accidental spillage or leakage from piping
systems. The working clearance space shall
include the zone described in 110.26(A). No
architectural appurtenance or other equipment
shall be located in this zone
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Table 110.26(A)(1) Working Space. Revised
110.27 Guarding of Live Parts. Revise-
(4) By elevation of 2.5 m (8 ft) or more above
the floor or other working surface as shown
in 110.27(A)(4)(a) or (b) below: .
(a) A minimum of 2.5 m (8 ft) for 50 to 300
volts.
(b) A minimum of 2.6 m (8 ½ ft) for 301 to
600 volts.
110.27 Guarding of Live Parts.
(A) Live Parts Guarded Against Accidental
Contact. Except as elsewhere required or
permitted by this Code, live parts of electrical
equipment operating at 50 volts or more to 1000
volts, nominal shall be guarded against accidental
contact by approved enclosures, or by any of the
following:
(4) By elevation above the floor or other working
surface as follows shown in 110.27(A)(4)(a) or (b)
below:
a. A minimum of 2.5 m (8 ft) for 50 volts to 300
volts between ungrounded conductors.
b. A minimum of 2.6 m (8 ½ ft 6 in.) for 301 volts
to 600 volts between ungrounded conductors.
c. A minimum if 2.62 m (8 ft. 7 in.) for 601 volts to
1000 volts between ungrounded conductors.
110.28 Enclosure Types. Enclosures (other
than surrounding fences or walls) of
switchboards, switchgear, panelboards,
industrial control panels, motor control
centers, meter sockets, enclosed switches,
transfer switches, power outlets, circuit
breakers, adjustable-speed drive systems,
pullout switches, portable power distribution
110.28 Enclosure Types. Enclosures (other than
surrounding fences or walls covered in 110.31) of
switchboards, switchgear, panelboards, industrial
control panels, motor control centers, meter
sockets, enclosed switches, transfer switches,
power outlets, circuit breakers, adjustable-speed
drive systems, pullout switches, portable power
distribution equipment, termination boxes,
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equipment, termination boxes, general-
purpose transformers, fire pump controllers,
fire pump motors, and motor controllers,
rated not over 600 volts nominal and
intended for such locations, shall be marked
with an enclosure-type number as shown in
Table 110.28.
Table 110.28 shall be used for selecting these
enclosures for use in specific locations other
than hazardous (classified) locations. The
enclosures are not intended to protect
against conditions such as condensation,
icing, corrosion, or contamination that may
occur within the enclosure or enter via the
conduit or unsealed openings.
general-purpose transformers, fire pump
controllers, fire pump motors, and motor
controllers, rated not over 600 1000 volts nominal
and intended for such locations, shall be marked
with an enclosure-type number as shown in Table
110.28.
Table 110.28 shall be used for selecting these
enclosures for use in specific locations other than
hazardous (classified) locations. The enclosures
are not intended to protect against conditions
such as condensation, icing, corrosion, or
contamination that may occur within the
enclosure or enter via the conduit or unsealed
openings.
110.33 Entrance to Enclosures and Access to
Working Spaces.
(1) Large Equipment. On switchboard
switchgear and control panels exceeding 1.8
m (6 ft) in width, there shall be one entrance
at each end of the equipment. A single
entrance to the required working space shall
be permitted where either of the conditions
in 110.33(A)(1)(a) or (A)(1)(b) is met.
110.33 Entrance to Enclosures and Access to
Working Spaces.
(2) Guarding. Where bare energized parts at any
voltage or insulated energized parts above 600
1000 volts, nominal. To ground are located
adjacent to such entrance, they shall be suitably
guarded.
110.34 Working Space and Guarding.
(D) Illumination. Illumination shall be provided
for all working spaces about electrical equipment.
Control by automatic means only shall not be
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permitted. The lighting outlets shall be arranged
so that persons changing lamps or making repairs
on the lighting system are not endangered to live
parts, or other equipment.
The points of control shall be located so that
persons are not likely to come in contact with any
live part or moving part of the equipment while
turning on the lights.
Table 110.34(A) Minimum Depth of Clear
Working Space at Electrical Equipment. Revised.
Table 110.34(E) Elevation of Unguarded Live
Parts Above Working Space. Revised.
CHAPTER 2 WIRING AND PROTECTION CHAPTER 2 WIRING AND PROTECTION
ARTICLE 200 Use and Identification of
Grounded Conductors
ARTICLE 200 Use and Identification of Grounded
Conductors
200.2 General.
(A) Insulation. The grounded conductor,
where if insulated, shall have insulation that
is (1) suitable, other than color, for any
ungrounded conductor of the same circuit
on circuits for systems of less than 1000 volts
or less, or impedance grounded neutral
systems of 1 kV over 1000 volts, and over, or
(2) rated not less than 600 volts for solidly
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grounded neutral systems of over 1000 volts
1 kV and over as described in 250.184(A).
200.4 Neutral Conductors. Neutral
conductors shall be installed in accordance
with 200.4(A) and (B).
(A) Installation. Neutral conductors shall not
be used for more than one branch circuit, for
more than one multiwire branch circuit, or
for more than one set of ungrounded feeder
conductors unless specifically permitted
elsewhere in this Code.
(B) Multiple Circuits. Where more than one
neutral conductor associated with different
circuits is in an enclosure, grounded circuit
conductors of each circuit shall be identified
or grouped to correspond with the
unmarked circuit conductor(s) by wire
markers, cable ties, or similar means in at
least one location within the enclosure.
Exception No. 1: The requirement for
grouping or identifying shall not apply if the
branch-circuit or feeder conductors enter
from a cable or a raceway unique to the
circuit that makes the grouping obvious.
Exception No. 2: The requirement for
grouping or identifying shall not apply where
the branch-circuit conductors pass through a
box or conduit body without a loop as
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described in 314.16(B)(1) or without a splice
or termination.
ARTICLE 210 BRANCH CIRCUITS ARTICLE 210 BRANCH CIRCUITS
210.2 210.3 Other Articles for Specific- Purpose
Branch Circuits. Table 210.3 lists references for
specific equipment and applications not located in
Chapters 5, 6, and 7 that Branch circuits shall
comply with this article and also with the
applicable provisions of other articles of this
Code, The provisions for branch circuits supplying
equipment listed in Table 210.2 amend or
supplement the provisions requirements in this
article.
Table 210.3 Specific-Purpose Branch Circuits.
Revised.
210.5 Identification for Branch Circuits. (C)
Identification of Ungrounded Conductors.
Revised.
210.5 Identification for Branch Circuits.
(C) (1) Branch Circuits Supplied from More Than
One Nominal Voltage System.
(b) Add- The label shall be of sufficient durability
to withstand the environment involved and shall
not be handwritten.
Exception: In existing installations where a voltage
system(s) already exists and a different voltage
system is being added, it shall be permissible to
mark only the new system voltage. Existing
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unidentified systems shall not be required to be
identified at each termination, connection, and
splice point in compliance with 210.5(C)(1) (a) and
(b). Labeling shall be required at each voltage
system distribution equipment to identify that
only one voltage system has been marked for a
new system(s). The new system label(s) shall
include the words “other unidentified systems
exist on the premises.”
(C)(2) Branch Circuits Supplied from Direct-
Current Systems.
(a) Positive Polarity.
(4) An approved permanent marking means such
as sleeving or shrink-tubing that is suitable for the
conductor size, at all rumination, connection, and
splice points, with imprinted plus signs (+) or the
word POSITIVE or POS durably marked on
insulation or a color other than green, white, gray,
or black.
(b) Negative Polarity.
(4) An approved permanent marking means such
as sleeving or shrink-tubing that is suitable for the
conductor size, at all rumination, connection, and
splice points, with imprinted minus signs (-) or the
word NEGATIVE or NEG durably marked on
insulation or a color other than green, white, gray,
or red.
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210.6 Branch-Circuit Voltage Limitations.
(D) (3) Luminaires powered from direct-current
systems where either of the following apply:
a. The luminaire contains a listed, dc-rated ballast
that provides isolation between the dc power
source and the lamp circuit and protection from
electric shock when changing lamps.
b. The luminaire contains a listed, dc-rated ballast
and has no provision for changing lamps.
210.8 Ground-Fault Circuit-Interrupter
Protection for Personnel.
(A) Dwelling Units. Add-
(9) Bathtubs or shower stalls- where
receptacles are installed within 1.8 m (6 ft) of
the outside edge of the bathtub or shower
stall.
(10) Laundry Areas
(B) Other than Dwelling Units. Add-
(4) Outdoors
Exception to No. 1 to (3): Receptacles on
rooftops shall not be required to be readily
accessible other than from the rooftop.
210.8 Ground-Fault Circuit-Interrupter
Protection for Personnel. Ground-fault circuit-
interrupter protection for personnel shall be
provided as required in 210.8(A) through (D) (E).
The ground-fault circuit-interrupter shall be
installed in a readily accessible location.
For the purposes of this section, when
determining distance from receptacles the
distance with be measured as the shortest path
the cord of an appliance connected to the
receptacle would follow without piercing a floor,
wall, ceiling, or fixed barrier, or passing through a
door, doorway, or window.
(A) Dwelling Units.
(5) Unfinished basements- for purposes of this
section, unfinished basements are defined as
portions or areas of the basement not intended as
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(8) Garages, service bays, and similar areas
other than vehicle exhibition halls and
showrooms where electrical diagnostic
equipment, electrical hand tools, or portable
lighting equipment are to be used.
(D) Kitchen Dishwasher Branch Circuit. GFCI
protection shall be provided for outlets that
supply dishwashers installed in dwelling unit
locations.
habitable rooms and limited to storage areas,
work areas, and the like
(7) Sinks- where receptacles are installed within
1.8 m (6 ft) from the top inside of the outside
edge of the sink.
(B) Other than Dwelling Units. All single-phase
receptacles rated 150 volts to ground or less, 50
amperes or less and three-phase receptacles
rated 150 volts to ground or less, 100 amperes or
less installed in the following location shall have
ground-fault circuit-interrupter protection for
personnel All 125-volt, single-phase. 15- and 20-
ampere receptacles installed in the locations
specified in 210.8(B)(1) through (8) shall have
ground-fault circuit-interrupter protection for
personnel.
(5) Sinks- where receptacles are installed within
1.8 m (6 ft) from the top inside of the outside
edge of the sink.
(9) Crawl spaces- at or below grade level.
(10) Unfinished portions or areas of the basement
not intended as habitable space.
(E) Crawl Space Lighting Outlets. New section.
210.12(B) Branch Circuit Extensions or
Modifications. Deleted.
210.12 Arc-Fault Circuit-Interrupter
Protection. Arc-fault circuit-interrupter
protection shall be provided as required in
210.12(A), (B), and (C). The arc-fault circuit
210.12 Arc-Fault Circuit-Interrupter Protection.
(C) (B) Dormitory Units. All 120-volt, single-phase,
15- and 20-ampere branch circuits supplying
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interrupter shall be installed in a readily
accessible location.
(A) Dwelling Unit. Completely revised.
(B) Branch Circuit Extensions or
Modifications- Dwelling Unit. Add-
Exception: AFCI protection shall not be
required where the extension of existing
conductors is not more than 1.8 m (6 ft) and
does not include any additional outlets or
devices.
outlets and devices installed in dormitory unit
bedrooms, living rooms, hallways, closets,
bathrooms, and similar rooms shall be protected
by any of the means described in a listed arc-fault
circuit interrupter meeting the requirements of
210.12(A)(1) through (6) as appropriate.
(C) Guest Rooms and Guest Suites. New section.
210.18 Rating. New section.
210.22 Permits. New section.
210.52 Dwelling Unit Receptacle Outlets.
(A)(2)(1) Any space 600 mm (2 ft) or more in
width (including space measured around corners)
and unbroken along the floor line by doorways
and similar openings, fireplaces, and fixed
cabinets that do not have countertops or similar
work surfaces.
(B)(1)
Exception No. 2: In addition to the receptacles
specified by 210.52, a receptacle outlet to serve a
specific appliance The receptacle outlet for
refrigeration equipment shall be permitted to be
supplied from an individual branch circuit rated
15 amperes or greater.
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(G)(1) Garages. In each attached garage and in
each detached garage with electric power, . The
branch circuit supplying this receptacle(s) shall
not supply outlets outside of the garage. at least
one receptacle outlet shall be installed in each
vehicle bay and not more than 1.7 m (5 ½ ft)
above the floor for each car space.
210.62 Show Windows. At least one A 125-
volt, single-phase, 15- or 20-ampere-rated
receptacle outlet
shall be installed within 450 mm (18 in.) of
the top of a
show window for each 3.7 linear m (12 linear
ft) or major
fraction thereof of show window area
measured horizontally at its maximum width.
210.64 Electrical Service Area. New section. 210.64 Electrical Service Areas. At least one 125-
volt, single-phase, 15- or 20-ampere-rated
receptacle outlet shall be installed in an accessible
location within 7.5 m (25 ft) of the indoor within
15 m (50 ft) of the electrical service equipment.
The required receptacle outlet shall be located
within the same room or area as the service
equipment.
Exception No. 1: The receptacle outlet shall not
be required to be installed in one- and two-family
dwellings.
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Exception No. 2: When the service voltage is
greater than 120 volts to ground, a receptacle
outlet shall not be required for services dedicated
to equipment covered in Articles 675 and 682.
210.70 Lighting Outlets Required.
(A)(1) Habitable Rooms. At least one wall switch-
controlled lighting outlet shall be installed in
every habitable room, kitchen, and bathroom.
(2) Additional Locations. Additional lighting
outlets shall
be installed in accordance with the following:
(A)(2)(a), (A)(2)(b), and (A)(2)(c).
(a) (1) At least one wall switch–controlled lighting
outlet
shall be installed in hallways, stairways, attached
garages, and detached garages with electric
power.
(b) (2) For dwelling units, attached garages, and
detached garages with electric power, at least
one wall switch–
controlled lighting outlet shall be installed to
provide illumination on the exterior side of
outdoor entrances or exits with grade level
access. A vehicle door in a garage shall not be
considered as an outdoor entrance or exit.
(c) (3) Where one or more lighting outlet(s) are
installed
for interior stairways, there shall be a wall switch
at each
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floor level, and landing level that includes an
entryway, to control the lighting outlet(s) where
the stairway between floor levels has six risers or
more.
Exception to (A)(2)(a)(1), (A)(2)(b) (2), and
(A)(2)(c)(3): In hallways, in stairways, and at
outdoor entrances, remote, central, or automatic
control of lighting shall be permitted.
(4) Lighting outlets controlled in accordance with
210.70(A)(2)(3) shall not be controlled by use of
dimmer switches unless they provide the full
range of dimming control at each location.
(C) Other Than Dwelling Units All Occupancies.
For attics and underfloor
Spaces, utility rooms, and basements containing
equipment requiring servicing, such as
heating, air-conditioning, and refrigeration
equipment, at
least one lighting outlet containing a switch or
controlled
by a wall switch shall be installed where these
spaces are used for storage or contain equipment
requiring servicing in such spaces. At least one
point of control shall be at the usual point of
entry to these spaces. The lighting outlet shall be
provided at or near the equipment requiring
servicing.
210.71 Meeting Rooms. New section.
ARTICLE 215 FEEDERS ARTICLE 215 FEEDERS
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215.2 Minimum Rating and Size.
(A) Feeders Not More Than 600 Volts.
(1) General. Feeder conductors shall have an
ampacity not less than required to supply
the load as calculated in Parts III, IV, and V of
Article 220. Conductors shall be sized to
carry not less than the larger of
215.2(A)(1)(a) or (b).
(a) Where a feeder supplies continuous loads
or any combination of continuous and
noncontinuous loads, the The minimum
feeder-circuit conductor size, before the
application of any adjustment or correction
factors, shall have an allowable ampacity not
less than the noncontinuous load plus 125
percent of the continuous load.
(b) The minimum feeder conductor size shall
have an allowable ampacity not less than the
maximum load to be served after the
application of any adjustment or correction
factors.
Exception No. 1: If the assembly, including
the overcurrent devices protecting the
feeder(s), is listed for operation at 100
percent of its rating, the allowable ampacity
of the feeder conductors shall be permitted
215.2 Minimum Rating and Size.
(A)(1) General.
Exception No. 1: If the assembly, including the
overcurrent devices protecting the feeder(s), is
listed for operation at 100 percent of its rating,
the allowable ampacity of the feeder conductors
shall be permitted to be not less than the sum of
the continuous load plus the noncontinuous load.
Exception No. 2: Where a portion of a feeder is
connected at both its supply and load ends
separately installed pressure connections as
covered in 110.14(C)(2). It shall be permitt4ed to
have an allowable ampacity not less the sum of
the continuous load plus the noncontinuous load.
No portion of s feeder installed under the
provisions of this exception shall extend into an
enclosure containing either the feeder supply or
the feeder load terminations, as covered in
110.14(C)(1).
Exception No. 2 3: Grounded conductors that are
not connected to an overcurrent device shall be
permitted to be sized at 100 percent of the
continuous and noncontinuous load.
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to be not less than the sum of the continuous
load plus the noncontinuous load.
Exception No. 2: Grounded conductors that
are not connected to an overcurrent device
shall be permitted to be sized at 100 percent
of the continuous and noncontinuous load.
215.3 Overcurrent Protection.
Exception No. 2: Overcurrent protection for
feeders over between 600 volts to 1000 volts
nominal, shall comply with Parts I through
VIII of Article 240. Feeders over 1000 volts,
nominal, shall comply with Part IX with Part
IX of Article 240.
215.12 Identification for Feeders. Revised
section.
Add-
(1) Feeders Supplied from More Than
One Nominal Voltage System. New
section.
(2) Feeders Supplied from Direct-
Current Systems. New section.
215.12 Identification for Feeders.
(C)(2) Feeders Supplied from Direct-Current
Systems.
(a)(4) All approved permanent marking means
such as sleeving or shrink-tubing that is suitable
for the conductor size, at all terminals,
connections, and splice points, with imprinted
plus signs (+) or the word POSITIVE or POS durably
marked on insulation of a color other than green,
white, gray, or black.
(b)(4) All approved permanent marking means
such as sleeving or shrink-tubing that is suitable
for the conductor size, at all terminals,
connections, and splice points, with imprinted
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minus signs (-) or the word NEGATIVE or NEG
durably marked on insulation of a color other
than green, white, gray, or red.
ARTICLE 220 BRANCH-CIRCUIT, FEEDER,
AND SERVICE CALCULATIONS
ARTICLE 220 BRANCH-CIRCUIT, FEEDER, AND
SERVICE CALCULATIONS
220.3 Other Articles for Specific-Purpose
Calculations. New section.
220.12 Lighting Load for Specified
Occupancies.
Exception: Where the building is designed
and constructed to comply with an energy
code adopted by the local authority, the
lighting load shall be permitted to be
calculated at the values specified in the
energy code where the following conditions
are met:
(1) A power monitoring system is
installed that will provide continuous
information regarding the total
general lighting load of the building.
(2) The power monitoring system will
be set with alarm values to alert the
building owner or manager if the
lighting load exceeds the values set
by the energy code.
220.12 Lighting Load for Specified Occupancies
Exception No. 1: Where the building is designed
and constructed to comply with an energy code
adopted by the local authority, the lighting load
shall be permitted to be calculated at the values
specified in the energy code where the following
conditions are met:
(1) A power monitoring system is installed
that will provide continuous information
regarding the total general lighting load of
the building.
(2) The power monitoring system will be set
with alarm values to alert the building
owner or manager if the lighting load
exceeds the values set by the energy code.
(3) The demand factors specified in 220.42
are not applied to the general lighting
load.
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(3) The demand factors specified in
220.42 are not applied to the general
lighting load.
Exception No. 2: Where a building is designed and
constructed to comply with an energy code
adopted by the local authority and specifying an
overall lighting density of lss than13.5 volt-
amperes/13.5 m2 (1.2 volt-amperes/1.2 ft2), the
unit lighting loads in Table 220.12 for office and
bank areas within the building shall be permitted
to be reduced by 11 volt-amperes/11 m2 (1 volt-
amperes. 1 ft2).
ARTICLE 225 Outside Branch Circuits and
Feeders
ARTICLE 225 Outside Branch Circuits and Feeders
225.4 Conductor Covering. Where within 3.0
m (10 ft) of
any building or structure other than
supporting poles or
towers, open individual (aerial) overhead
conductors shall be insulated or covered for
the nominal voltage. Conductors in cables or
raceways, except Type MI cable, shall be of
the rubber-covered type or thermoplastic
type and, in wet locations, shall comply with
310.10(C). Conductors for festoon lighting
shall be of the rubber-covered or
thermoplastic type.
Exception: Equipment grounding conductors
and grounded
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circuit conductors shall be permitted to be
bare or covered as
specifically permitted elsewhere in this Code.
225.10 Wiring in Buildings (or Other Buildings).
Revised.
225.11 Feeder and Branch-Circuit
Conductors Entering, Exiting, or Attached to
Buildings or Structures. New section.
225.12 Open-Conductor Supports. Open
conductors
shall be supported on knobs, glass or porcelain
knobs, racks, brackets, or strain insulators that
are made of glass, porcelain, or other approved
materials.
225.14 Open-Conductor Spacings. Revise-
(A) 600 1000 Volts, Nominal, or Less.
Conductors of 600 1000 volts, nominal, or
less, shall comply with the spacings provided
in Table 230.51(C).
(B) Over 600 1000 Volts, Nominal.
Conductors of over 600 1000 volts, nominal,
shall comply with the spacings provided in
110.36 and 490.24.
225.17 Masts as Supports. Only feeder or
branch-circuit conductors specified within
this section shall be permitted to be
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attached to the feeder and/or branch-circuit
mast. Masts Where a mast is used for the
support of final spans of feeders or branch
circuits shall be installed in accordance with
225.17(A) and (B).
(A) Strength. The mast , it shall be of
adequate strength or be supported
by braces or guys to withstand safely
the strain imposed by the overhead
feeder or branch-circuit conductors
drop. Hubs intended for use with a
conduit that serves as a mast for
support of feeder or branch-circuit
conductors shall be identified for use
with a mast.
(B) Attachment. Feeder and/or branch-
circuit conductors shall not be
attached to a mast between a
weatherhead or the end of the
conduit and a coupling where the
coupling is located above the last
point of securement to the building
or other structure or is located above
the building or other structure.
Where raceway-type masts are used, all
raceway fittings shall be identified for use
with masts. Only the feeder or branch circuit
conductors specified within this section shall
be permitted to be attached to the feeder
and/or branch-circuit mast.
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225.20 Mechanical Protection of Conductors
Protection Against Physical Damage. Mechanical
protection of Conductors installed on buildings,
structures, or poles shall be protected against
physical damage as provided for services in
230.50.
225.30 Number of Supplies.
(A) Special Conditions. Add-
(7) Electric vehicle charging systems listed,
labeled, and identified for more than a single
branch circuit or feeder.
225.32 Location. The disconnection shall be
installed either inside or attached to the
outside of the building or structure served or
where the conductors pass through the
building or structure.
The disconnecting means shall be at a
readily accessible location nearest the point
of entrance of the conductors. For the
purpose of this section, the requirements in
230.6 shall be permitted to be utilized.
Exception No. 1: For installations under
single management, where documented safe
switching
procedures are established and maintained
for disconnection and where the installation
is monitored by qualified individuals, the
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disconnected means shall be permitted to be
located elsewhere on the premises.
Exception No. 2: For buildings or other
structures qualified under the provisions of
Article 685, the disconnecting means shall
be permitted to be located elsewhere on the
premises.
Exception No. 3: For towers or poles used
as lighting standards, the disconnecting
means shall be permitted to be located
elsewhere on the premises.
Exception No. 4: For poles or similar
structure used only for support of signs
installed in accordance with Article 600, the
disconnecting means shall be permitted to be
located elsewhere on the premises.
Exception No. 5: The disconnecting means
may be located independent of the building
or structure served, in direct line of sight,
but not to exceed thirty feet (30’).
Exception No. 6: The service disconnecting
means may be installed within a building
when an external remote shunt trip switch is
provided. All shunt trip switches shall be
located at seven feet (7’) above finish grade
at a location approved by the fire
department. All shunt trip switches
shall be located within a twelve inch (12”)
equilateral triangle, red in color.
225.36 Suitable for Service Equipment. The
disconnecting means specified in 225.31
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shall be comprised of a circuit breaker,
molded case switch, snap switch, or other
approved means. Where applied in
accordance with 250.32(B), Exception 1, the
disconnecting means shall be suitable for use
as service equipment.
Exception: For garages and outbuildings on
residential property, a snap switch or a set of
3-way or 4-way snap switches shall be
permitted as the disconnecting means.
225.36 Suitable for Service Equipment Type. 225.36 Type of Disconnecting Means.
225.38 Disconnect Construction. Disconnecting
means
shall meet the requirements of 225.38(A) through
(D).
Exception: For garages and outbuildings on
residential
property, snap switches or 3-way or 4-way snap
switches shall be permitted as the disconnecting
means.
(C) Disconnection of Grounded Conductor.
Where the
building or structure disconnecting means does
not disconnect the grounded conductor from the
grounded conductors in the building or structure
wiring, other means shall be provided for this
purpose at the location of disconnecting means. A
terminal or bus to which all grounded conductors
can be attached by means of pressure connectors
shall be permitted for this purpose.
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In a multisection switchboard or swichgear,
disconnects for the grounded conductor shall be
permitted to be in any section of the switchboard
or switchgear; if the provided any such
switchboard section or switchgear section is
marked to indicate a grounded conductor
disconnect is contained within the equipment.
225.52 Disconnecting Means.
(A) Location. A building or structure
disconnecting means
shall be located in accordance with 225.32,
or if not readily accessible, it shall be
operable by mechanical linkage from a
readily accessible point. For multibuilding
industrial installations under single
management it shall be permitted to be
electrically operated by a readily accessible,
similarly located remote-control device in a
separate building or structure.
225.56 Inspections and Tests.
(A) Pre-Energization and Operating Tests.
The complete
electrical system design, including settings
for protective, switching, and control circuits,
shall be prepared in advance and made
available on request to the authority having
jurisdiction and shall be performance tested
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when first installed on-site. Each protective,
switching, and control circuit shall be
adjusted in accordance with the system
design recommendations of the protective
device study and tested by actual operation
using current injection or equivalent
methods as necessary to ensure that each
and every such circuit operates correctly to
the satisfaction of the authority having
jurisdiction.
ARTICLE 230 Services ARTICLE 230 Services
230.6 Conductors Considered Outside the
Building. Revise-
(5) Where installed within rigid metal
conduit (Type RMC) or intermediate metal
conduit (IMC) used to accommodate the
clearance requirement in230.24 and routed
directly through the eave but not a wall of a
building. in overhead service masts on the
outside surface of the building traveling
through the eave of that building to meet
the requirements of 230.24
230.7 Other Conductors in Raceway or Cable.
Conductors other than service conductors shall
not be installed in the same service raceway or
service cable in which the service conductors are
installed.
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Exception No. 1: Grounding electrode conductors
or supply side and equipment bonding
Jumpers or conductors shall be permitted within
service raceways.
Exception No. 2: Load management control
conductors having overcurrent protection shall be
permitted within service raceways.
230.10 Vegetation as Support. Vegetation such as
trees shall not be used for support of overhead
service conductors or service equipment.
230.14 Clearances.
(B) Vertical Clearance for Overhead Service
Conductors. Add-
(5) 7.5 m (241/2 ft.) over tracks of railroads.
230.28 Service Masts as Supports. Where a
service mast is used for the support of
service-drop conductors, it shall be of
adequate strength or be supported by braces
or guys to withstand safely the strain
imposed by the service drop. Where
raceway-type service masts are used, all
raceway fittings shall be identified for use
with service masts. Only power service-drop
or overhead service conductors shall be
permitted to be attached to a service mast.
Service masts used for the support of
service-drop or overhead service conductors
shall be installed in accordance with
230.28(A) and (B).
(A) Strength. The service mast shall be of
adequate strength or be supported
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by braces or guys to withstand safely
the strain imposed by the service-
drop or overhead service conductors.
Hubs intended for use with a conduit
that serves as a service mast shall be
identified for use with service
entrance equipment.
(B) Attachment. Service-drop or
overhead service conductors shall not
be attached to a service made
between a weatherhead or the end
of the conduit or the end of the
conduit and a coupling, where the
coupling is located above the last
point of securement to the building
or other structure or is located above
the building or other structure.
230.29 Supports over Buildings. Service
conductors
passing over a roof shall be securely supported by
substantial structures. For a grounded system,
where the substantial structure is metal, it shall
be bonded by means of a bonding jumper and
listed connector to the grounded overhead
service conductor. Where practicable, such
supports shall be independent of the building.
230.30 Insulation Installation.
(A) Insulation. Renumbered.
(B) Wiring Methods. New subsection.
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230.42 Minimum Size and Rating.
(A) General. Insert-
(2) The sum of the noncontinuous load plus
the continuous load after the application of
any adjust or correction factors.
230.42 Minimum Size and Rating.
(A) General. The ampacity of the service-entrance
conductors shall before the application of any
adjustment or correction factors shall not be less
than either 230.42(A)(1) or (A)(2). Loads shall be
determined in accordance with Part III, IV, or V of
Article 220, as applicable. Ampacity shall be
determined from 310.15. The maximum allowable
current of busways shall be that value for which
the busway has been listed or labeled.
(1) Where the service-entrance conductors supply
continuous loads or any combination of
noncontiunous and continuous loads, the
minimum service-entrance conductor size shall
have an allowable ampacity not less than the sum
of the noncontinuous loads plus 125 percent of
continuous loads.
Exception No. 1: Grounded conductors that are
not connected to an overcurrent device shall be
permitted to be sized at 100 percent of the sum of
the continuous and noncontinuous load.
(3) Exception No. 2: The sum of the
noncontinuous load plus the continuous load if
the service-entrance conductors terminate in a
overcurrent device where both the overcurrent
device and tis assembly are listed for operation at
100 percent of their rating shall be permitted.
(2) The sum of the noncontinuous load plus the
continuous load after the application of and
adjustment or correction factors.
(3) The sum of the noncontinuous load plus the
continuous load if the service-entrance
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conductors terminate in a overcurrent device
where both the overcurrent device and tis
assembly are listed for operation at 100 percent
of their rating.
230.44 Cable Trays. Cable tray systems shall be
permitted to support service-entrance
conductors. Cable trays used to support service-
entrance conductors shall contain only service-
entrance conductors and shall be limited to the
following methods:
(1) Type SE cable
(2) Type MC cable
(3) Type MI cable
(4) Type IGS cable
(5) Single conductors 1/0 and larger that are listed
for use in cable tray.
Such cable trays shall be identified with
permanently
affixed labels with the wording “Service-Entrance
Conductors.” The labels shall be located so as to
be visible after installation with a spacing not to
exceed 3 m (10 ft) so that the service-entrance
conductors are able to be readily traced through
the entire length of the cable tray.
230.66 Marking. Service equipment rated at 600
volts or
less shall be marked to identify it as being suitable
for use
as service equipment. All service equipment shall
be listed or field labeled. Individual meter socket
enclosures shall not be considered service
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equipment but shall be listed and rated for the
voltage and ampacity of the service.
Exception: Meter sockets supplied by and under
the exclusive control of an electric utility shall not
be required to be listed.
230.70(A)(1) Readily Accessible Location.
The service disconnection means shall be
installed outside of a building or other
structure at a readily accessible location
nearest the point of entrance of the service
conductors. The disconnecting means may
be located independent of the
building or structure served, in direct line of
sight, but not to exceed thirty feet (30’). at a
readily accessible location either outside of a
building or structure or inside nearest the
point of entrance of the service conductors.
Exception: The service disconnecting
means may be installed within a building
when an external remote shunt trip switch is
provided. All shunt trip switches shall be
located at seven feet (7’) above finish grade
at a location approved by the fire
department. All shunt trip switches shall be
located within a twelve inch (12”)
equilateral triangle, red in color.
230.75 Disconnection of Grounded Conductor.
Where
the service disconnecting means does not
disconnect the
grounded conductor from the premises wiring,
other means shall be provided for this purpose in
the service equipment. A terminal or bus to which
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all grounded conductors can be attached by
means of pressure connectors shall be permitted
for this purpose. In a multisection switchboard or
swichgear, disconnects
for the grounded conductor shall be permitted to
be in
any section of the switchboard or switchgear; if
the provided any such switchboard or switchgear
section is marked to indicate a grounded
conductor disconnect is located within.
230.82 Equipment Connected to the Supply Side
of Service Disconnect.
(6) Solar photovoltaic systems, fuel cell systems,
wind electric systems, energy storage systems or
interconnected electric power production
sources.
230.91 Location. The service overcurrent device
shall be
an integral part of the service disconnecting
means or shall be located immediately adjacent
thereto. Where fuse are used as the service
overcurrent device, the disconnecting means shall
be located ahead of the supply side of the fuses.
ARTICLE 240 Overcurrent Protection ARTICLE 240 Overcurrent Protection
240.1 Scope. Parts I through VII of this article
provide the general requirements for
overcurrent protection and overcurrent
protective devices not more than 600 1000
volts, nominal. Part VIII covers overcurrent
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protection for those portions of supervised
industrial installations operating at voltages
of not more than 600 1000 volts, nominal.
Part IX covers overcurrent protection over
600 1000 volts, nominal.
240.13 Ground-Fault Protection of
Equipment. Ground-fault protection of
equipment shall be provided in accordance
with the provisions of 230.95 for solidly
grounded wye electrical systems of more
than 150 volts to ground but not exceeding
600 1000 volts phase-to-phase for each
individual device used as a building or
structure main disconnecting means rated
1000 amperes or more.
The provisions of this section shall not apply
to the disconnecting means for the
following:
(1) Continuous industrial processes where a
nonorderly shutdown will introduce
additional or increased hazards
(2) Installations where ground-fault
protection is provided by other requirements
for services or feeders
(3) Fire pumps
240.21 Location in Circuit.
(B)(1) Taps Not over 3 m (10 ft) Long.
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(1) The ampacity of the tap conductors is
a. Not less than the combined calculated
loads on the circuits supplied by the tap
conductors, and
b. Not less than the rating of the equipment
containing an overcurrent device(s) supplied
by the tap conductors or not less than the
rating of the overcurrent protective device at
the termination of the tap conductors.
Exception to b: Where listed equipment,
such as a surge protective device(s) [SPD(s)],
is provided with specific instructions on
minimum conductor sizing, the ampacity of
the tap conductors supplying that equipment
shall be permitted to be determined based
on the manufacturer’s instruction.
(C)(2) Transformer Secondary Conductors
Not over 3 m (10 ft) Long.
(1) The ampacity of the secondary
conductors is
a. Not less than the combined calculated
loads on the circuits supplied by the
secondary conductors, and
b. Not less than the rating of the equipment
containing overcurrent device(s) supplied by
the secondary conductors or not less than
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the rating of the overcurrent-protective
device at the termination of the secondary
conductors.
Exception. Where listed equipment, such as
surge protective device(s) [SPD(s)], is
provided with specific instructions on
minimum conductor sizing, the capacity of
the tap conductors supplying that equipment
shall be permitted to be determined based
on the manufacturer’s instructions.
240.24 Location in or on Premises.
(A) Accessibility. Switches containing fuses and
circuit breakers shall Overcurrent devices shall be
readily accessible and shall be installed so that the
center of the grip of the operating handle of the
switch or circuit breaker, when in its highest
position, is not more than 2.0 m (6 ft 7 in.) above
the floor or working platform, unless one of the
following applies:
(1) For busways, as provided in 368.17(C).
(2) For supplementary overcurrent protection, as
described in 240.10.
(3) For overcurrent devices, as described in
225.40 and
230.92.
(4) For overcurrent devices adjacent to utilization
equipment that they supply, access shall be
permitted to be by portable means.
Exception: The use of a tools shall be permitted to
access overcurrent devices located within listed
industrial control panels or similar enclosures.
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240.51(B) Replacement Only. Plug fuses of
the Edison-based shall be used only for
replacement in existing installations where
there is no evidence of overfusing or
tampering. In any existing building where
alterations or additions are made to any of
the premises wiring, all fuse holders shall
comply with Section 240.54.
240.87 Arc Energy Reduction. New section. 240.87 Arc Energy Reduction.
(B) Method to Reduce Clearing Time. One of the
following or approved equivalent means shall be
provided:
Add or revise-
(5) An instantaneous trip setting that is less than
the available arcing current
(6) In instantaneous override that is less than the
available arcing current
(7) An approved equivalent means.
ARTICLE 250 Grounding and Bonding ARTICLE 250 Grounding and Bonding
Table 250.3 Additional Grounding and Bonding
Requirements. Revised.
250.22 Circuits Not to Be Grounded.
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(6) Class 2 load side circuits for suspended ceiling
low-voltage power grid distribution systems as
provided in 393.60(B).
250.30 Grounding Separately Derived
Alternating-Current Systems. In addition to
complying with 250.30(A)for grounded
systems, or as provided in 250.30(B) for
ungrounded systems, separately derived
systems shall comply with 250.20, 250.21,
250.22, and 250.26, as applicable. Multiple
separately derived systems that are
connected in parallel shall be installed in
accordance with 250.30.
(A)(1) System Bonding Jumper.
Exception No. 2: If the building or structure is
supplied by a feeder from an outdoor
transformer, a A system bonding jumper at
both the source and the first disconnecting
means shall be permitted if doing so does not
establish a parallel path for the grounded
conductor. If a grounded conductor is used in
this manner, it shall not be smaller than the
size specified for the system bonding jumper
but shall not be required to be larger than
the ungrounded conductor(s). For the
purposes of this exception, connection
through the earth shall not be considered as
providing a parallel path.
250.30 Grounding Separately Derived
Alternating-Current Systems.
(A)(1) System Bonding Jumper.
Exception No. 2: If the building or structure is
supplied by a feeder from an outdoor transformer
separating derived system, a system bonding
jumper at both the source and the first
disconnecting means shall be permitted if doing so
does not establish a parallel path for the
grounded conductor. If a grounded conductor is
used in this manner, it shall not be smaller than
the size specified for the system bonding jumper
but shall not be required to be larger than the
ungrounded conductor(s). For the purposes of this
exception, connection through the earth shall not
be considered as providing a parallel path.
(A)(4) Grounding Electrode. The building or
structure grounding electrode system shall be
used as the grounding electrode for the
separately derived system. If located outdoors,
the grounding electrode shall be in accordance
with 250.30(C). as near as practicable to, and
preferably in the same area as, the grounding
electrode conductor connection to the system.
The grounding electrode shall be the nearest of
one of the following:
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(1) Metal water pipe grounding electrode as
specified in
250.52(A)(1)
(2) Structural metal grounding electrode as
specified in
250.52(A)(2)
Exception No. 1: Any of the other electrodes
identified in
250.52(A) shall be used if the electrodes specified
by
250.30(A)(4) are not available.
Exception No. 2 to (1) and (2): If a separately
derived
system originates in is listed and identified as
suitable for use as service equipment, equipment
suitable for use as
service equipment, the grounding electrode used
for the
service or feeder equipment shall be permitted to
be used as the grounding electrode for the
separately derived system.
(A)(6) (a) Common Grounding Electrode
Conductor. The common grounding electrode
conductor shall be permitted to be one of the
following:
(1) A conductor of the wire type not smaller than
3/0 AAWG copper or 250 kcmil aluminum
(2) A metal water pipe that complies with
250.68(C)(1)
(2) (3) The metal structural frame of the building
or structure that complies with 250.52(A)(2)
250.68(C)(2) or is connected to the grounding
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electrode system by a conductor of that shall not
be smaller than 3/0 AWG copper of 250 kcmil
aluminum
250.32 Buildings or Structures Supplied by a
Feeder(s) or Branch Circuit(s).
(1) Supplied by a Feeder or Branch Circuit.
Add-
Exception No. 2: If system bonding jumpers
are installed in accordance with
250.30(A)(1), Exception No. 2, the feeder
grounded circuit conductor at the building or
structure served shall be connected to the
equipment grounding conductors, grounding
electrode conductor, and the enclosure for
the first disconnecting means.
250.52 Grounding Electrodes.
(A)(2) Metal In-Ground Support Structures. New
subsection.
(A)(7)(B) Not Permitted for Use as Grounding
Electrodes. Add-
(3) The structures and structural reinforcing steel
described in 680.26(B)(1) and (B)(20.
250.62 Grounding Electrode Conductor
Material. The grounding electrode conductor
shall be of copper, aluminum, or copper-clad
aluminum, or the items as permitted in
250.62 Grounding Electrode Conductor Material.
(B) Securing and Protection Against Physical
Damage. Revised.
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250.68(C). The material selected shall be
resistant to any corrosive condition existing
at the installation or shall be protected
against corrosion. Conductors of wire type
The conductor shall be solid or stranded,
insulated, covered, or bare.
250.64 Grounding Electrode Conductor
Installation.
(B) Securing and Protection Against Physical
Damage. Add- Grounding electrode
conductors and grounding electrode bonding
jumpers shall not be required to comply with
300.5.
(D)(2). Individual Grounding Electrode
Conductors. A
grounding electrode conductor shall be
connected between the grounding electrode
system and one or more of the following, as
applicable:
(1) Grounded conductor in each service
equipment disconnecting means
enclosure
(2) Equipment grounding conductor
installed with the feeder
(3) Supply-side bonding jumper
Each grounding electrode conductor shall be
sized in accordance with 250.66 based on
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the service-entrance or feeder conductor(s)
supplying the individual disconnecting
means.
(D)(3) Common Location. A grounding
electrode conductor shall be connected in a
wireway or other accessible enclosure on the
supply side of the disconnecting means to
one or more of the following, as applicable:
(1) to the Grounded service conductor(s)
(2) Equipment grounding conductor installed
with the feeder
(3) Supply-side bonding jumper
In a wireway or other accessible enclosure
on the supply side of the service
disconnecting means. The connection shall
be made with exothermic welding or a
connector listed as grounding and bonding
equipment. The grounding electrode
conductor shall be sized in accordance with
250.66 based on the service-entrance
conductor(s) at the common location where
the connection is made.
250.66 Size of Alternating-Current Grounding
Electrode
Conductor.
(A) Connections to Rod, Pipe, or Plate Electrodes.
Where If the grounding electrode conductor or
bonding jumper is connected to a single or
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multiple rod, pipe, or plate electrodes, or any
combination thereof, as permitted described in
250.52(A)(5) or (A)(7), does not extend on to
other types of electrodes that require a larger size
conductor, the grounding electrode conductor
that portion of the conductor that is the sole
connection to the grounding electrode(s) shall not
be required to be larger than 6 AWG copper wire
or 4 AWG aluminum wire.
(B) Connections to Concrete-Encased Electrodes.
Where If the grounding electrode conductor or
bonding jumper is connected to a single or
multiple concrete-encased electrode(s) as
permitted described in 250.52(A)(3), does not
extend on to other types of electrodes that
require a larger size of conductor, the grounding
electrode conductor that portion of the conductor
that is the sole connection to the grounding
electrode(s) shall not be required to be larger
than 4 AWG copper wire.
(C) Connections to Ground Rings. Where If the
grounding electrode conductor or bonding jumper
is connected to a ground ring as permitted
described in 250.52(A)(4), does not extend on to
other types of electrodes that require a larger size
of conductor, the grounding electrode conductor
that portion of the conductor that is the sole
connection to the grounding electrode shall not
be required to be larger than the conductor used
for the ground ring.
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250.68 Grounding Electrode Conductor and
Bonding Jumper Connection to Grounding
Electrodes.
(C) Grounding Electrode Connections. Add-
(3) A concrete-encased electrode of either
the conductor type, reinforcing rod or bar
installed in accordance with 250.52(A)(3)
extended from its location within the
concrete to an accessible location above the
concrete shall be permitted.
250.68 Grounding Electrode Conductor and
Bonding Jumper Connection to Grounding
Electrodes.
(C) Grounding Electrode Connections.
(1) Interior metal water piping located not more
than 1.52 m (5 ft) from the point of entrance to
the building shall be permitted to extend the
connection to an electrode(s). Interior metal
water piping located more than 1.52 m (5 ft) from
the point of entrance to the building shall not be
used as a conductor to interconnect electrodes
that are part of the grounding electrode system.
Exception: In industrial, commercial, and
institutional
buildings or structures, if conditions of
maintenance and
supervision ensure that only qualified persons
service the
installation, interior metal water piping located
more than 1.52 m (5 ft) from the point of entrance
to the building shall be permitted as a bonding
conductor to interconnect electrodes that are part
of the grounding electrode system, or as a
grounding electrode conductor, if the entire
length, other than short sections passing
perpendicularly through walls, floors, or ceilings,
of the interior metal water pipe that is being used
for the conductor is exposed.
2.The metal structural frame of a building shall be
permitted to be used as a conductor to
interconnect electrodes that are part of the
grounding electrode system, or as a grounding
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electrode conductor. Hold-down bolts securing
the structural steel column that are connected to
a concrete-encased electrode that complies with
250.52 (A)(3) and is located in the support footing
or foundation shall be permitted to connect the
metal structural frame of the building or structure
to the concrete encased grounding electrode. The
hold-down bolts shall be connected to the
concrete-encased electrode by welding, the usual
steel tie wires, or other approved means.
(3) A rebar-type concrete-encased electrode of
either the conductor type, reinforcing rod or bar
installed in accordance with 250.52(A)(3) with an
additional rebar section extended from its
location within the concrete to an accessible
location that is not subject to corrosion above the
concrete shall be permitted for connection of
grounding electrode conductors and bonding
jumpers. The rebar extension shall not be
exposed to contact with the earth without
corrosion protection.
250.94 Bonding for Other Communication
Systems. Revised.
(A) General The Intersystem Boding Termination
Device. Revised.
(B) Other Means. New subsection.
250.96(A) General Metal raceways, cable
trays, cable armor, cable sheath, enclosures,
frames, fittings, and other metal non-current-
carrying parts that are to serve as ground
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conductors, with or without the use of
supplementary equipment grounding
conductors, shall be effectively bonded
where necessary to ensure electrical
continuity and the capacity to conduct safely
any fault current likely to be imposed on
them. Any nonconductive paint, enamel, or
similar coating shall be removed at threads,
contact points, and contact surfaces or be
connected by means of fittings
designed so as to make such removal
unnecessary. The Authority Having
Jurisdiction shall require a supplementary
grounding conductor where a metallic
raceway is subject to damage or likely to be
disturbed.
FPN: An example of ‘subject to damage’
might be a surface mounted conduit along a
traffic path in a warehouse. An example of
‘likely to be disturbed’ might be conduit
across a rooftop, where re-roofing
operations will require the conduit to be
removed.
250.104 Bonding of Piping Systems and
Exposed Structural Steel.
(B) Other Metal Piping. If installed in, or
attached to, a building or structure, a metal
piping system(s), including gas piping, that is
likely to become energized shall be bonded
to any of the following:
250.104 Bonding of Piping Systems and Exposed
Structural Metal
(A) Metal Water Piping. The metal water piping
system
shall be bonded as required in (A)(1), (A)(2), or
(A)(3) of
this section. The bonding jumper(s) shall be
installed in
accordance with 250.64(A), (B), and (E). The
points of
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(1) Equipment grounding conductor for
the circuit that is likely to energize
the piping system
(2) Service equipment enclosure
(3) Grounded conductor at the service
(4) Grounding electrode conductor, if of
sufficient size
(5) One or more grounding electrodes
used
the service equipment enclosure; the
grounded conductor at the service; the
grounding electrode conductor, if of
sufficient size; or to one or more grounding
electrodes used. The bonding conductor(s)
or jumper(s) shall be sized in accordance
with 250.122, using the rating of the circuit
that is likely to energize the piping system(s).
The equipment grounding conductor for the
circuit that is likely to energize the piping
shall be permitted to serve as the bonding
means. The points of attachment of the
bonding jumper(s) shall be accessible.
attachment of the bonding jumper(s) shall be
accessible.
(1) General. Metal water piping system(s)
installed in or
attached to a building or structure shall be
bonded to any of the following:
(1) Service equipment enclosure
(2) Grounded conductor at the service
(3) Grounding electrode conductor where of
sufficient size
(4) One or more grounding electrodes used, if
the grounding electrode conductor or
bonding jumper to the grounding
electrode is of sufficient size.
The bonding jumper(s) shall be sized installed in
accordance with Table 250.66 except as
permitted in 250.104(A)(2) and (A)(3) 250.64(A),
250.64(B), and 250.64(E). The points of
attachment of the bonding jumper(s) shall be
accessible. The bonding jumper(s) shall be sized in
accordance with Table 250.102(C)(1) except as
permitted in 250.104(A)(2) and 250.104(A)(3).
(B) Other Metal Piping. If installed in, or attached
to, a building or structure, a metal piping
system(s), including gas piping, that is likely to
become energized shall be bonded to any of the
following:
(1) Equipment grounding conductor for the
circuit that is likely to energize the piping
system
(2) Service equipment enclosure
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(3) Grounded conductor at the service
(4) Grounding electrode conductor, if of
sufficient size
(5) One or more grounding electrodes used, if
the grounding electrode conductor or
bonding jumper to the grounding
electrode is of sufficient size.
C) Structural Metal. Exposed structural metal that
is interconnected to form a metal building frame
and is not
intentionally grounded or bonded and is likely to
become
energized shall be bonded to any of the following:
(1) Service equipment enclosure
(2) Grounded conductor at the service
(3) Disconnecting means for buildings or
structures supplied by a feeder or branch
circuit
(4) Grounding electrode conductor, if of
sufficient size
(5) One or more grounding electrodes used, if
the grounding electrode conductor or
bonding jumper to the grounding
electrode is of sufficient size.
The bonding conductor(s) or jumper(s) shall be
sized in accordance with Table 250.66
250.102(C)(1) and installed in accordance with
250.64(A), 250.64(B), and 250.64(E). The points of
attachment of the bonding jumper(s) shall be
accessible unless installed in compliance with
250.68(A), Exception No. 2.
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(D) Separately Derived Systems. Metal water
piping systems and structural metal that is
interconnected to form a building frame shall be
bonded to separately derived systems in
accordance with 250.104(D)(1) through
250.104(D)(3).
250.119 Identification or Equipment
Grounding Conductors. Add-
Exception No. 2: Flexible cords having an
integral insulation and jacket without an
equipment grounding conductor shall be
permitted to have a continuous outer finish
that is green.
Exception No. 3: Conductors with green
insulation shall be permitted to be used as
ungrounded signal conductors where
installed between the output terminations of
traffic signal control and traffic signal
indicating heads. Signaling circuits installed
in accordance with this exception shall
include an equipment grounding conductor
in accordance with 250.118. Wire-type
equipment grounding conductors shall be
bare or have insulation or covering that is
green with one or more yellow stripes.
250.119 Identification or Equipment Grounding
Conductors.
(C) Flexible Cord. Equipment grounding
conductors in flexible cords shall be insulated and
An uninsulated equipment grounding conductor
shall be permitted, but, if individually covered,
the covering shall have a continuous outer finish
that is either green or green with one or more
yellow stripes.
250.121 Use of Equipment Grounding
Conductors. Add-
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Exception: A wire-type equipment grounding
conductor installed in compliance with
250.6(A) and the applicable requirements for
both the equipment grounding conductor
and the grounding electrode conductor and
the grounding electrode conductor in Parts
II, III, and VI of this article shall be permitted
to serve as both an equipment grounding
conductor and a grounding electrode
conductor.
250.122 Size of Equipment Grounding
Conductors. Revise-
(B) Increased in Size. Where ungrounded
conductors are increased in size from the
minimum size that has sufficient ampacity
for the intended installation, wire type,
equipment grounding conductors, where
installed, shall be increased in size
proportionately according to the circular mil
area of the ungrounded conductors.
250.122 Size of Equipment Grounding
Conductors.
(F) Conductors in Parallel. For circuits of parallel
conductors as permitted in 310.10(H), the
equipment grounding conductor shall be installed
in accordance with (1) of (2). Where conductors
are installed in parallel in multiple raceways or
cables as permitted in 310.10(H), the equipment
grounding conductors, where used, shall be
installed in parallel in each raceway or cable.
Where conductors are installed in parallel in the
same raceway, cable, or cable tray as permitted in
310.10(H), a single equipment grounding
conductor shall be permitted. Equipment
grounding conductors installed in cable tray shall
meet the minimum requirements of
392.10(B)(1)(c).
Each equipment grounding conductor shall be
sized incompliance with 250.122.
250.130 Equipment Grounding Conductor
Connections.
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(C) Nongrounding Receptacle Replacement
or Branch Circuit Extensions. Insert-
(4) An equipment grounding conductor that
is part if another branch circuit that
originates from the enclosure where the
branch circuit for the receptacle or branch
circuit originates.
250.166 Size of the Direct-Current
Grounding Electrode
Conductor. The size of the grounding
electrode conductor for a dc system shall be
as specified in 250.166(A) and (B), except as
permitted by 250.166(C) through (E).
The grounding electrode conductor for a dc
system shall meet the sizing requirements in
this section but shall not be required to be
larger than 3/0 copper or 250 kcmil
aluminum.
250.167 Direct-Current Ground-Fault
Detection. New section.
250.186 Ground-Fault Circuit Conductor
Brought to Service Equipment. New section
and subsections inserted.
250.187 Impedance Grounded Neutral System.
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(B) Identified and Insulated. The neutral
conductor shall comply with both of the
following:
(1) The neutral conductor shall be identified.
(2) The neutral conductor shall be insulated for
the maximum neutral voltage.
of an impedance grounded neutral system shall
be identified, as well as fully insulated with the
same insulation as the phase conductors.
250.194 Grounding and Bonding of Fences
and Other Metal Structures. New section
and subsections.
ARTICLE 280
Surge Arresters, Over 1000 Volts
280.12 Uses Not Permitted. New section.
ARTICLE 285 Surge-Protective Devices
(SPDs), 1000 Volts or Less
285.13 Type 4 and Other Component Type
SPDs. New section.
Chapter3 Wiring Methods and Materials
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ARTICLE 300 General Requirements for
Wiring Methods and Materials
ARTICLE 300 General Requirements for Wiring
Methods and Materials
300.7 Raceways Exposed to Different
Temperatures.
(B) Expansion, Expansion-Deflection, and
Deflection Fittings. Raceways shall be
provided with expansion, expansion
deflection, or deflection fittings where
necessary to compensate for thermal
expansion and contraction.
300.5 Underground Buildings
(G) Raceway Seals. Conduits or raceways through
which
moisture may contact live parts shall be sealed or
plugged at either or both ends. Spare and unused
raceways shall also be sealed. Sealants shall be
identified for use with the cable insulation,
conductor insulation, bare conductor, shield, or
other components.
300.22 Wiring in Ducts Not Used for Air
Handling, Fabricated Ducts for Environmental
Air, and Other Spaces for Environmental Air
(Plenum)
(B) Ducts Specifically Fabricated for
Environmental Air.
Exception: Wiring methods and cabling systems,
listed for use other spaces used for environmental
air (plenums), shall be permitted to be installed in
ducts specifically fabricated for environmental air-
handling purposes under the following conditions:
(1) The wiring methods and cabling systems
shall be permitted only if necessary to
connect to equipment or devices
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associated with the direct action upon or
sensing of the contained air, and
(2) The total length of such wiring methods or
cabling systems shall not exceed 1.2 m (4
ft).
300.37 Aboveground Wiring Method.
Exception: Airfield lighting cable used in series
circuits that are powered by regulators and
installed in restricted airport lighting vaults shall
be permitted as exposed cable installations.
300.38 Raceways in Wet Locations Above
Grade. New section
300.45 Warning Signs. New section
300.50 Underground Installations
(A)(2) Industrial Establishments. New
section.
ARTICLE 310
Conductors for General Wiring
310.15 Ampacities for Conductors Rated 0-
2000 Volts.
(A) (7) 120/240-Volt, 3-Wire, Single-Phase
Dwelling Services and Feeders. For one-
family dwellings and the individual dwelling
310.15 Ampacities for Conductors Rated 0-2000
Volts.
(A)(2) Selection of Ampacity. Where more than
one ampacity applies for a given circuit length,
the lowest value shall be used.
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units of two-family and multifamily
dwellings, service and feeder conductors
applied by a single-phase, 120/240-volt
system shall be permitted be sized in
accordance with 310.15(B)(7)(1) through (4).
(1) For a service rated 100 through 400 A,
the service conductors supplying the entire
loads associated with a one-family dwelling,
or the service conductors supplying the
entire load associated with an individual
dwelling unit in a two-family or multifamily
dwelling, shall be permitted to have an
ampacity not less than 83 percent of the
service rating.
(2) For a feeder rated 100 through 400 A, the
feeder conductors supplying the entire load
associated with a one-family dwelling, or the
feeder conductors supplying the entire load
associated with an individual dwelling, unit
to a two-family or multifamily dwelling, shall
be permitted to have an ampacity not less
than 83 percent of the feeder rating.
(3) In no case shall a feeder for an individual
dwelling unit be required to have an
ampacity greater than that specified in
310.15(B)(7)(1) or (2).
(4) Grounded conductors shall be permitted
to be sized smaller than the ungrounded
conductors, provided that the requirements
of 220.61 and 230.42 for service conductors
or the requirements of 215.2 and 220,61 for
feeder conductors are met.
Exception: Where two When different ampacities
apply to adjacent portions of a circuit, the higher
ampacity shall be permitted to be used if the total
portion(s) of the circuit with the lower capacity
does not exceed the lesser of beyond the point of
transition, a distance equal to 3.0 m (10 ft) or 10
percent of the total circuit length figured at the
higher ampacity, whichever is less.
(A)(7) 120/240-Volt, 3-Wire, Single-Phase
Dwelling Services and Feeders. For one-family
dwellings and the individual dwelling units of two-
family and multifamily dwellings, service and
feeder conductors applied by a single-phase,
120/240-volt system shall be permitted be sized
in accordance with 310.15(B)(7)(1) through (4).
For one-family dwellings and the individual units
of two-family and multifamily dwellings, single-
phase feeder conductors consisting of 2
ungrounded conductors and the neutral
conductor from a 208Y/120 volt system shall be
permitted to be sized in accordance with
310.15(B)(7)(1) through (3).
(1) For a service rated 100 through 400 A, the
service conductors supplying the entire loads
associated with a one-family dwelling, or the
service conductors supplying the entire load
associated with an individual dwelling unit in a
two-family or multifamily dwelling, shall be
permitted to have an ampacity not less than 83
percent of the service rating.
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individual dwelling units of one family, two-
family, and multifamily dwellings,
conductors, as listed in Table 310.15(B)(7),
shall be permitted as 120/240-volt, 3-wire,
single-phase service-entrance conductors,
service-lateral conductors, and feeder
conductors that serve as the main power
feeder to each dwelling unit and are installed
in raceway or cable with or without an
equipment grounding conductor. For
application of this section, the main power
feeder shall be the feeder between the main
disconnect and the panelboard that supplies,
either by
branch circuits or by feeders, or both, all
loads that are part or associated with the
dwelling unit. The feeder conductors to a
dwelling unit shall not be required to have an
allowable ampacity rating greater than their
service-entrance conductors. The grounded
conductor shall be permitted to be smaller
than the ungrounded conductors, provided
the requirements of 215.2, 220.61, and
230.42 are met.
(2) For a feeder rated 100 through 400 A, the
feeder conductors supplying the entire load
associated with a one-family dwelling, or the
feeder conductors supplying the entire load
associated with an individual dwelling, unit to a
two-family or multifamily dwelling, shall be
permitted to have an ampacity not less than 83
percent of the feeder rating.
(3) In no case shall a feeder for an individual
dwelling unit be required to have an ampacity
greater than that specified in 310.15(B)(7)(1) or
(2).
(4) Grounded conductors shall be permitted to be
sized smaller than the ungrounded conductors,
provided that the requirements of 220.61 and
230.42 for service conductors or the
requirements of 215.2 and 220,61 for feeder
conductors are met.
Where correction or adjustment factors are
required by 310.15(B)(2) or (3), they shall be
permitted to be applied to the ampacity
associated with the temperature rating of the
conductor.
ARTICLE 312
Cabinets, Cutout Boxes, and Meter Socket
Enclosures
ARTICLE 312
Cabinets, Cutout Boxes, and Meter Socket
Enclosures
312.1 Scope. This article covers the installation
and construction specifications of cabinets, cutout
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boxes, and meter socket enclosures. It does not
apply to equipment operating at over 1000 volts,
except as specifically referenced elsewhere in the
Code.
Table 312.6(A) Minimum Wire-Bending Space at
Terminals and Minimum Width of Wiring
Gutters. Revised.
312.8 Switch and Overcurrent Device. Revised.
ARTICLE 314 Outlet, Device, Pull, and
Junction Boxes; Conduit Bodies; Fittings;
and Handhole Enclosures
ARTICLE 314 Outlet, Device, Pull, and Junction
Boxes; Conduit Bodies; Fittings; and Handhole
Enclosures
314.15 Damp or Wet Locations. In damp or
wet locations, boxes, conduit bodies, outer
box hoods, and fittings shall be placed or
equipped so as to prevent moisture from
entering or accumulating within the box,
conduit body, outer box hoods, or fitting.
Boxes, conduit bodies, and fittings installed
in wet locations shall be listed for use in wet
locations. Approved drainage openings not
larger than 5 mm (1.4 in) shall be permitted
to be installed in the field in boxes or conduit
boxes listed for use in damp or wet location.
Fir installation of listed drain fittings, larger
openings are permitted to be installed in the
field in accordance with manufacturer’s
instructions.
314.15 Damp or Wet Locations. In damp or wet
locations, boxes, conduit bodies, outer box hoods,
and fittings shall be placed or equipped so as to
prevent moisture from entering or accumulating
within the box, conduit body, outer box hoods, or
fitting. Boxes, conduit bodies, and fittings
installed in wet locations shall be listed for use in
wet locations. Approved drainage openings not
smaller than 3 mm (1/8 in) and not larger than 5 6
mm (1/4 in) in diameter shall be permitted to be
installed in the field in boxes or conduit boxes
listed for use in damp or wet location. Fir
installation of listed drain fittings, larger openings
are permitted to be installed in the field in
accordance with manufacturer’s instructions.
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314.16 Number of Conduits in Outlet,
Device, and Junction Boxes, and Conduit
Bodies.
(B) (2) Add- A clamp assembly that
incorporates a cable termination for the
cable conductors shall be listed and marked
for use with specific nonmetallic boxes.
Conductors that originate within the clamp
assembly shall be included in conductor fill
calculations covered in 314.16(B)(1) as
though they entered from outside the box.
The clamp assembly shall not require a fill
allowance, but the volume of the portion of
the assembly that remains within the box
after installation shall be excluded from the
box volume as marked in 314.16(A)(2).
314.16 Number of Conduits in Outlet, Device,
and Junction Boxes, and Conduit Bodies.
(A) Box Volume Calculations. The volume of a
wiring
enclosure (box) shall be the total volume of the
assembled sections and, where used, the space
provided by plaster rings, domed covers,
extension rings, and so forth, that are marked
with their volume or are made from boxes the
dimensions of which are listed in Table 314.16(A).
Where a box is provided with one or more
securely installed barriers, the volume shall be
apportioned to each of the resulting spaces. Each
barrier, if not marked with its volume, shall be
considered to take up 8.2 cm3 (1/2 in3) if metal,
and 16.4 cm3 (1.0 in3) if nonmetallic.
(B) Box Fill Calculations. The volumes in
paragraphs
314.16(B)(1) through (B)(5), as applicable, shall be
added
together. No allowance shall be required for small
fittings such as locknuts and bushings. Each space
within a box, installed with a barrier shall be
calculated separately.
314.17(C) Nonmetallic Boxes and Conduit
Bodies. Nonmetallic boxes and conduit
bodies shall be suitable for the lowest
temperature-rated conductor entering the
box. Where nonmetallic boxes and conduit
bodies are used with messenger support
wiring, open wiring on insulators, or
314.17 Conductors Entering Boxes, Conduit
Bodies, or
Fittings.
(A) Openings to Be Closed. Openings
through which conductors enter shall be
closed in an approved manner adequately
closed.
314.17 Conductors Entering Boxes, Conduit
Bodies, or
Fittings.
(B) Metal Boxes and Conduit Bodies. Where
metal boxes
or conduit bodies are installed with messenger-
supported wiring, open wiring on insulators, or
concealed knob-and- tube wiring, conductors
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concealed knob-and-tube wiring, the
conductors shall enter the boxes through
individual holes. Where flexible tubing is
used to enclose the conductors, the tubing
shall extend from the last insulated support
to not less than 6 mm (1/4 in.) inside the box
and beyond any cable clamp.
Where nonmetallic-sheathed cable or
multiconductor Type UF cable is used, the
sheath shall extend not less than 6 mm (1/4
in.) inside the box and beyond any cable
clamp. In all instances, all permitted wiring
methods shall be secure to the boxes.
Exception: Where nonmetallic-sheathed
cable or multiconductor Type UF cable is
used with single gang boxes not larger than
a nominal size 57mm x 100 mm (2 ¼ in. x 4
in.) mounted in walls or ceilings, and where
the cable is fastened within 200 mm (8 in.)
of the box measured
along the sheath and the sheath extends
through a cable knockout not less than 6
mm. (1/4 in.) securing the cable to the box
shall not be required. Multiple cables entries
shall be permitted in a single cable knockout
opening.
shall enter through insulating bushings or, in dry
locations, through flexible tubing extending from
the last insulating support to not less than 6 mm
(1⁄4 in.) inside the box and beyond any cable
clamps. Where nonmetallic sheathed cable or
multiconductor Type UF cable is used, the sheath
shall extend not less than 6 mm (1/4 in) inside the
box and beyond any cable clamp. Except as
provided in 300.15(C), the wiring shall be firmly
secured to the box or conduit body. Where
raceway or cable is installed with metal boxes or
conduit bodies, the raceway or cable shall be
secured to such boxes and conduit bodies.
314.20 In Wall or Ceiling Flush-Mounted
Installations. Installations within or behind In
walls or ceilings with a
surface of concrete, tile, gypsum, plaster, or other
noncombustible material, boxes employing a
flush-type cover or faceplate shall be made
installed so that the front edge of the box, plaster
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ring, extension ring, or listed extender will not be
set back of the finished surface more than 6 mm
(1⁄4 in.).
Installations within a surface In walls and ceilings
constructed of wood or other combustible surface
material, boxes, plaster rings, extension rings, or
listed extenders shall extend to be flush with the
finished surface or project therefrom.
314.25 Covers and Canopies. Add- Screws
used for the purpose of attaching covers, or
other equipment, to the box shall be either
machine screws matching the thread gauge
and size that is integral to the box or shall be
in accordance to the box or shall be in
accordance with the manufacturer’s
instructions.
314.28 Pull and Junction Boxes and Conduit
Bodies.
(3) Smaller Dimensions. Listed boxes or
listed conduit bodies of dimensions less than
those required in 314.28(A)(1) and (A)(2)
shall be permitted for installations of
combinations of conductors that are less
than the maximum conduit or tubing fill (of
conduits or tubing being used) permitted by
Table 1 of Chapter 9.
Listed conduit bodies of dimensions less than
those required in 314.28(A)(2), and having a
radius of the curve to the centerline not less
than that indicated in Table 2 of Chapter 9
for one-shot and full-shoe benders, shall be
314.28 Pull and Junction Boxes and Conduit
Bodies.
(A) Minimum Size. For raceways containing
conductors
of 4 AWG or larger that are required to be
insulated, and for cables containing conductors of
4 AWG or larger, the minimum dimensions of pull
or junction boxes installed in a raceway or cable
run shall comply with 314.28(A)(1) through (A)(3).
Where an enclosure dimension is to be calculated
based on the diameter of entering raceways, the
diameter shall be the metric designator (trade
size) expressed in the units of measurement
employed.
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permitted by Table 1 of Chapter 9, These
conduit bodies shall be marked to show they
have been specifically evaluated in
accordance with this provision.
Where the permitted combinations of
conductors for which the box or conduit
body has been listed are less than the
maximum conduit or tubing fill permitted by
Table 1 of Chapter 9, the box or conduit
body shall be permanently marked with the
maximum number and maximum size of
conductors permitted. provided the box or
conduit body has been listed for, and is
permanently marked with, the maximum
number and maximum size of conductors
permitted.
(3)Smaller Dimensions. Listed boxes or listed
conduit bodies of dimensions less than those
required in 314.28(A)(1) and (A)(2) shall be
permitted for installations of combinations of
conductors that are less than the maximum
conduit or tubing fill (of conduits or tubing being
used) permitted by Table 1 of Chapter 9.
Listed conduit bodies of dimensions less than
those required in 314.28(A)(2), and having a
radius of the curve to the centerline not less than
that indicated in Table 2 of Chapter 9 for one-shot
and full-shoe benders, shall be permitted by Table
1 of Chapter 9, These conduit bodies shall be
marked to show they have been specifically
evaluated in accordance with this provision.
Where the permitted combinations of conductors
for which the box or conduit body has been listed
are less than the maximum conduit or tubing fill
permitted by Table 1 of Chapter 9, the box or
conduit body shall be permanently marked with
the maximum number and maximum size of
conductors permitted. For other conductor sizes
and combinations, the total cross-sectional area
of the fill shall not exceed the cross-sectional area
of the conductors specified in the marking, based
on the type of conductor identified as part of the
product listing.
(E) Power Distribution Blocks.
(1) Installation. Power distribution blocks
installed in
boxes shall be listed. Power distribution blocks
installed on the line side of the service equipment
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shall be listed and marked “suitable for use on the
line side of service equipment” or equivalent.
314.70 General.
(A) Pull and Junction Boxes. Where pull and
junction boxes are used on systems over 600
1000 volts, the installation shall comply with
the provisions of Part IV and with the
following general provisions of this article:
(1) Part I, 314.2; 314.3; and 314.4
(2) Part II, 314.15; 314.17; 314.20; 314.23(A),
(B), or (G);
314.28(B); and 314.29
(3) Part III, 314.40(A) and (C); and 314.41
(B) Conduit Bodies. Where conduit bodies
are used on systems over 600 1000 volts, the
installation shall comply with the provisions
of Part IV and with the following general
provisions of this article:
(1) Part I, 314.4
(2) Part II, 314.15; 314.17; 314.23(A), (E), or
(G); and
314.29
(3) Part III, 314.40(A); and 314.41
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(C) Handhole Enclosures. Where handhole
enclosures are used on systems over 600
1000 volts, the installation shall comply with
the provisions of Part IV and with the
following general provisions of this article:
(1) Part I, 314.3; and 314.4
(2) Part II, 314.15; 314.17; 314.23(G);
314.28(B); 314.29;
and 314.30
ARTICLE 330
Metal-Clad Cable: Type MC
330.6 Listing Requirements. New section.
330.15 Exposed Work. New section.
330.10 Uses Permitted
(11) In wet locations where a corrosion-
resistant jacket is provided over the metallic
covering and any of the following conditions
are met:
a. The metallic covering is impervious to
moisture.
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b. A moisture-impervious jacket resistant to
moisture is provided under the metal
covering.
c. The insulated conductors under the
metallic covering are listed for use in wet
locations, and a corrosion resistant jacket is
provided over the metallic sheath.
330.30 Securing and Supporting.
(B) Securing. Unless otherwise provided,
cables shall be secured at intervals not
exceeding 1.8 m (6 ft). Cables containing four
or fewer conductors sized no larger than 10
AWG shall be secured within 300 mm (12 in.)
of every box, cabinet, fitting, or other cable
termination. In vertical installations, fixed
cables with ungrounded conductors 250
kcmil and larger shall be permitted to be
secured at intervals not exceeding 3 m (10
ft).
(D)Unsupported Cables.
(3) Is Type MC of the interlocked armor type
in length not exceeding 900 mm (3 ft) from
the last point where it is securely fastened
and is used to connect equipment where
flexibility is necessary to minimize the
transmission of vibration from equipment or
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to provide flexibility for equipment that
requires movement after installation.
330.112 Insulation.
(A) 600 1000 Volts. Insulated conductors in
sizes 18 AWG and 16 AWG shall be of a type
listed in Table 402.3, with a maximum
operating temperature not less than 90°C
(194°F) and as permitted by 725.49.
Conductors larger than 16 AWG shall be of a
type listed in Table 310.104(A) or of a type
identified for use in Type MC cable.
(B) Over 600 1000 Volts. Insulated
conductors shall be of a type listed in Table
310.104(C) (B) through Table 310.104(E) (C).
ARTICLE 332
Mineral-Insulated, Metal-Sheathe Cable: Type
MI
332.6 Listing Requirements. New section.
ARTICLE 334
Nonmetallic-Sheathed Cable: Type NM,
NMC, and NMS
ARTICLE 334
Nonmetallic-Sheathed Cable: Type NM, NMC,
and NMS
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334.6 Listing Requirements. New section.
334.40 Boxes and Fittings.
(B) Devices of Insulating Material. Self-
Contained switches, self-contained
receptacles, and nonmetallic-sheathed cable
in interconnector witch, outlet, and tap
devices of insulating material that are listed
shall be permitted to be used without boxes
in exposed cable wiring and for repair wiring
rewiring in existing buildings where the cable
is concealed and fished. Openings in such
devices shall form a close fit around the
outer covering of the cable, and the device
shall fully enclose the part of the cable from
which any part of the covering has been
removed. Where connections to conductors
are by binding-screw terminals, there shall
be available many terminals as conductors.
ARTICLE 333
Rigid Metal Conduit: Type RMC
ARTICLE 336
Power and Control Tray Cables, Type TC
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336.6 Listing Requirements. New section.
336.10 Uses Permitted. Type TC cable shall be
permitted
to be used as follows:
(1) For power, lighting, control, and signal circuits.
(2) In cable trays, including those with
mechanically discontinuous segments up to 300
mm (1 ft).
(3) In raceways.
(4) In outdoor locations supported by a
messenger wire.
(5) For Class 1 circuits as permitted in Parts II and
III of
Article 725.
(6) For non–power-limited fire alarm circuits if
conductors
comply with the requirements of 760.49.
(7) In industrial establishments where the
conditions of
maintenance and supervision ensure that only
qualified
persons service the installation, and where the
cable is
continuously supported and protected against
physical
damage using mechanical protection, such as
struts,
angles, or channels, Type TC tray cable that
complies
with the crush and impact requirements of Type
MC
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cable and is identified for such use with the
marking
Type TC–ER shall be permitted Between a cable
tray
and the utilization equipment or devices provided
all of the following apply:
(a) The cable is Type TC-ER.
(b) The cable is installed in industrial
establishments where the conditions of
maintenance and supervision ensure that only
qualified persons service the installation.
(c) The cable is continuously supported and
protected against physical damage using
mechanical protection, such as struts, angles,
or channels.
(d) The cable that complies with the crush and
impact requirements of Type MC cable and is
identified with for such use with the marking
Type TC–ER
(e) The cable shall is secured at intervals not
exceeding 1.8 m (6 ft).
(f) Equipment grounding for the utilization
equipment shall be provided by an
equipment grounding conductor within
the cable. In cables containing conductors
sized 6 AWG or smaller, the equipment
grounding conductor shall must be
provided within the cable or, at the time
of installation, one or more insulated
conductors shall must be permanently
identified as an equipment grounding
conductor in accordance with 250.119(B).
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Exception: Where not subject to physical damage,
Type
TC-ER shall be permitted to transition between
cable trays and between cable trays and
utilization equipment or devices for a distance not
to exceed 1.8 m (6 ft) without continuous support.
The cable shall be mechanically supported where
exiting the cable tray to ensure that the minimum
bending radius is not exceeded.
(8) Where installed in wet locations, Type TC
cable shall also be resistant to moisture and
corrosive agents.
(9) In one- and two-family dwelling units, Type TC-
ER cable containing both power and control
conductors that is identified for pulling through
structural members shall be permitted. Type TC-
ER cable used as interior wiring shall be installed
per the requirements of Part II of Article 334.
Exception: Where used to connect a generator
and associated equipment having terminals rated
750C (1400F) or higher, the cable shall not be
limited in ampacity by 334.80 or 340.80.
(10) Direct buried, where identified for such use.
ARTICLE 338
Service-Entrance Cable: Types SE and USE
ARTICLE 338
Service-Entrance Cable: Types SE and USE
338.6 Listing Requirements. New section.
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338.10 Uses Permitted.
(B) Branch Circuits or Feeders.
(4) Installation Methods for Branch Circuits
and Feeders.
(b) Exterior Installations. In addition to the
provisions
of this article, service-entrance cable used
for feeders or
branch circuits, where installed as exterior
wiring, shall be installed in accordance with
Part I of Article 225. The cable shall be
supported in accordance with 334.30. Type
USE cable installed as underground feeder
and branch circuit cable shall comply with
Part II of Article 340.
Exception: Single-conductor Type USE and
multi-rated USE conductors shall not be
subject to the ampacity limitations of Part II
of Article 340.
338.10 Uses Permitted.
(B) Branch Circuits or Feeders.
(4) Installation Methods for Branch Circuits and
Feeders.
(a) Interior Installations. In addition to the
provisions
of this article, Type SE service-entrance cable
used for interior wiring shall comply with the
installation requirements of Part II of Article 334,
excluding 334.80.
For Type SF cable with ungrounded conductor
sizes 10 AWG and smaller, where installed in
thermal insulation, the ampacity shall be in
accordance with the 60°C (140°F) conductor
temperature rating. The maximum conductor
temperature rating shall be permitted to be used
for ampacity adjustment and correction purposes,
if the final derated ampacity does not exceed that
for a 60°C (140°F) rated conductor.
ARTICLE 340
Underground Feeder and Branch-Circuit
Cable: Type UF
ARTICLE 340
Underground Feeder and Branch-Circuit Cable:
Type UF
340.6 Listing Requirements. New section.
ARTICLE 342
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Intermediate Metal Conduit: Type IMC
342.14 Dissimilar Metals. Where practicable,
dissimilar
metals in contact anywhere in the system shall be
avoided to eliminate the possibility of galvanic
action.
Aluminum fittings and enclosures shall be
permitted to be used with galvanized steel IMC
where not subject to severe corrosive influences.
Stainless steel IMC shall only be used with
stainless steel fittings and approved accessories,
outlet boxes, and enclosures.
342.100 Construction. New section.
342.120 Marking. Each length shall be clearly and
durably marked at least every 1.5 m (5 ft) with the
letters IMC. Each length shall be marked as
required in the first sentence of in 110.21(A).
ARTICLE 344
Rigid Metal Conduit: Type RMC
ARTICLE 344
Rigid Metal Conduit: Type RMC
344.14 Dissimilar Metals. Where practicable,
dissimilar
metals in contact anywhere in the system shall be
avoided to eliminate the possibility of galvanic
action. Aluminum fittings and enclosures shall be
permitted to be used with galvanized steel RMC,
and galvanized steel fittings and enclosures shall
be permitted to be used with aluminum RMC
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where not subject to severe corrosive influences.
Stainless steel RMC shall only be used with
stainless steel fittings and approved accessories,
outlet boxes, and enclosures.
344.30 Securing and Supporting. Revised.
344.100 Construction. New section. 344.100 Construction.
(1) Steel (ferrous) with or without protective
coatings.
(2) Aluminum (nonferrous).
ARTICLE 348
Flexible Metal Conduit: Type FMC
ARTICLE 348
Flexible Metal Conduit: Type FMC
348.30 Securing and Supporting.
A) Securely Fastened.
Exception No. 4: Lengths not exceeding 1.8 m
(6 ft) from the last point where the raceway
is securely fastened for connections within an
accessible ceiling to luminaire(s) or other
equipment. For the purposes of this
exception, listed flexible metal conduit
fittings shall be permitted as a means of
support.
348.30 Securing and Supporting.
A) Securely Fastened. Add-
Where used, cable ties shall be listed and be
identified for securement and support.
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ARTICLE 350
Lightweight Flexible Metal Conduit: Type
LFMC
350.42 Couplings and Connectors. Only
fittings listed for use with LFMC shall be
used. Angle connectors shall not be
concealed. Straight LFMC fittings shall be
permitted for direct burial where marked.
ARTICLE 356
Lightweight Flexible Nonmetallic Conduit:
Type LFNC
356.30 Securing and Supporting. Type LFNC-
B shall be
securely fastened and supported in
accordance with one of the following:
(1) Where installed in lengths exceeding 1.8
m (6 ft), the
conduit shall be securely fastened at
intervals not exceeding 900 mm (3 ft) and
within 300 mm (12 in.) on
each side of every outlet box, junction box,
cabinet, or
fitting.
(2) Securing or supporting of the conduit
shall not be required where it is fished,
356.30 Securing and Supporting. Type LFNC-B
LFNC shall be securely fastened and supported in
accordance with one of the following:
(1) Where installed in lengths exceeding 1.8 m (6
ft), the
conduit shall be securely fastened at intervals not
exceeding 900 mm (3 ft) and within 300 mm (12
in.) on
each side of every outlet box, junction box,
cabinet, or
fitting. Where used, cable ties shall be listed as
suitable for the application and for securing and
supporting.
(2) Securing or supporting of the conduit shall not
be required where it is fished, installed in lengths
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installed in lengths not exceeding 900 mm (3
ft) at terminals where flexibility is
required, or installed in lengths not
exceeding 1.8 m
(6 ft) from a luminaire terminal connection
for tap conductors to luminaires permitted in
410.117(C).
(3) Horizontal runs of LFNC supported by
openings through framing members at
intervals not exceeding 900 mm (3 ft) and
securely fastened within 300 mm (12 in.) of
termination points shall be permitted.
(4) Securing or supporting of LFNC-B shall
not be required
where installed in lengths not exceeding 1.8
m
(6 ft) from the last point where the raceway
is securely fastened for connections within
an accessible ceiling to luminaire(s) or other
equipment. For the purpose of 356.30, listed
liquidtight flexible nonmetallic conduit
fittings shall be permitted as a means of
support.
not exceeding 900 mm (3 ft) at terminals where
flexibility is
required, or installed in lengths not exceeding 1.8
m
(6 ft) from a luminaire terminal connection for tap
conductors to luminaires permitted in 410.117(C).
(3) Horizontal runs of LFNC LFNC supported by
openings through framing members at intervals
not exceeding 900 mm (3 ft) and securely
fastened within 300 mm (12 in.) of
termination points shall be permitted.
(4) Securing or supporting of LFNC-B shall not be
required
where installed in lengths not exceeding 1.8 m
(6 ft) from the last point where the raceway is
securely fastened for connections within an
accessible ceiling to luminaire(s) or other
equipment. For the purpose of 356.30, listed
liquidtight flexible nonmetallic conduit fittings
shall be permitted as a means of support.
356.60 Grounding and Bonding. Revised.
ARTICLE 358
Electrical Metallic Tubing Type EMT
358.10 Uses Permitted.
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(A) Exposed and Concealed. The use of EMT shall
be permitted for both exposed and concealed
work for the following:
(1) In concrete, in direct contact with the earth or
in areas subject to severe corrosive influences
where installed in accordance with 358.10(B).
(2) In dry, damp, or wet locations.
(3) In any hazardous (classified) location as
permitted by other articles in this Code.
(B) Corrosive Environments.
(1) Galvanized steel and Stainless steel EMT,
Elbows, and Fittings. New subsection.
(2) Supplementary Protection of Aluminum EMT.
New subsection.
(C) Cinder Fill. New section inserted.
358.12 Uses Not Permitted. EMT shall not be
used under
the following conditions:
(1) Where, during installation or afterward, it will
be subject to severe physical damage.
(2) Where protected from corrosion solely by
enamel.
(3) In cinder concrete or cinder fill where subject
to permanent moisture unless protected on all
sides by a layer of non-cinder concrete at least 50
mm (2 in.) thick or unless the tubing is at least 450
mm (18 in.) under the fill.
(4) In any hazardous (classified) location except as
permitted by other articles in this Code.
(5) (2) For the support of luminaires or other
equipment except conduit bodies no larger than
the largest trade size of the tubing.
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(6) Where practicable, dissimilar metals in contact
anywhere in the system shall be avoided to
eliminate the
possibility of galvanic action.
Exception: Aluminum fittings and enclosures shall
be permitted to be used with steel EMT where not
subject to severe corrosive influences.
358.30 Securing and Supporting.
(A) Securely Fastened. EMT shall be securely
fastened in
place at intervals not to exceed least every 3 m
(10 ft). In addition, each EMT run between
termination points shall be securely fastened
within 900 mm (3 ft) of each outlet box, junction
box, device box, cabinet, conduit body, or other
tubing termination.
Exception No. 1: Fastening of unbroken lengths
shall be
permitted to be increased to a distance of 1.5 m (5
ft) where structural members do not readily
permit fastening within 900 mm (3 ft).
Exception No. 2: For concealed work in finished
buildings
or prefinished wall panels where such securing is
impracticable, unbroken lengths (without
coupling) of EMT shall be permitted to be fished.
358.100 Construction. EMT shall be made of one
of the following:
(1) Steel with protective coatings
(2) Aluminum.
(3) Stainless steel
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Factory-threaded integral couplings shall be
permitted. Where EMT with a threaded integral
coupling is used, threads for both the tubing and
coupling shall be factory-made. The coupling and
EMT threads shall be designed so as to prevent
bending of the tubing at any part of the thread.
ARTICLE 362
Electrical Nonmetallic Tubing: Type ENT
362.30 Securing and Supporting.
(A) Securely Fastened. ENT shall be securely
fastened at
intervals not exceeding 900 mm (3 ft). In addition,
ENT
shall be securely fastened in place within 900 mm
(3 ft) of each outlet box, device box, junction box,
cabinet, or fitting where it terminates. Where
used, cable ties shall be listed as suitable for the
application and for securing and supporting.
Exception No. 1: Lengths not exceeding a distance
of
1.8 m (6 ft) from a luminaire terminal connection
for tap
connections to lighting luminaires shall be
permitted
without being secured.
Exception No. 2: Lengths not exceeding 1.8 m (6
ft) from the last point where the raceway is
securely fastened for
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connections within an accessible ceiling to
luminaire(s) or
other equipment.
Exception No. 3: For concealed work in finished
buildings
or prefinished wall panels where such securing is
impracticable,
unbroken lengths (without coupling) of ENT shall
be permitted to be fished.
ARTICLE 368
Busways
368.17 Overcurrent Protection.
(C) Feeder or Branch Circuits. Where a busway is
used
as a feeder, devices or plug-in connections for
tapping off
feeder or branch circuits from the busway shall
contain the overcurrent devices required for the
protection of the feeder or branch circuits. The
plug-in device shall consist of an externally
operable circuit breaker or an externally operable
fusible switch. Where such devices are mounted
out of reach and contain disconnecting means,
suitable means such as ropes, chains, or sticks
shall be provided for operating the disconnecting
means from the floor.
Exception No. 1: As permitted in 240.21.
Exception No. 2: For fixed or semifixed luminaires,
where
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the branch-circuit overcurrent device is part of the
luminaire cord plug on cord-connected luminaires.
Exception No. 3: Where luminaires without cords
are
plugged directly into the busway and the
overcurrent device is mounted on the luminaire.
Exception No. 4: Where the branch-circuit
overcurrent plug-in device is directly supplying a
readily accessible disconnect, a method of floor
operation shall not be required.
ARTICLE 370 Cablebus ARTICLE 370 Cablebus
370.2 Definition.
Cablebus. An assembly of units or sections
with insulated conductors with having
associated fittings forming a structured
system used to securely fasten or support
conductors and conductor terminations in a
completely enclosed, ventilated protective
metal housing. Cablebus is ordinarily
assembled at the point of installation from
the components furnished or specified by
the manufacturer in accordance with
instructions for the specific job. This
assembly is designed to carry fault current
and to withstand the magnetic forces of such
current.
370.10 Uses Permitted. Revised
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370.12 Uses not Permitted. New section. 370.12 Uses not Permitted. Cablebus shall not be
permitted to be installed in the following:
(1) In Hoistways
(2) In Hazardous (classified) locations, unless
specifically permitted in Chapter 5 approved for
the use
370.18 Cablebus Installation. New section. 370.18 Cablebus Cellular Concrete Floor
Raceways Installation. New section.
370.20 Conductor Size and Termination.
New section.
370.30 Securing and Support. New section.
370.42 Fittings. New section.
370.60 Grounding. New section.
370.80 Ampacity of Conductors. New
section.
370.120 Marking. New section.
ARTICLE 374 Cellular Metal Floor Raceways
374.2 Definitions.
Cellular Metal Floor Raceway. The hollow
spaces of cellular metal floors, together with
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suitable fittings, that may be approved as
enclosures enclosed channel for electrical
conductors.
374.11 Connection to Cabinets and
Extensions from Cells.
Connections between raceways and
distribution centers and wall outlets shall be
made by means of liquidtight flexible metal
conduit, flexible metal conduit where not
installed in concrete, rigid metal conduit,
intermediate metal conduit, electrical
metallic tubing, or approved fittings. Where
there are provisions for the termination of
an equipment grounding conductor, rigid
polyvinyl chloride conduit, reinforced
thermosetting resin nonmetallic conduit,
electrical nonmetallic tubing, or liquidtight
flexible nonmetallic conduit shall be
permitted. Where installed in concrete,
liquidtight flexible metal conduit and
liquidtight flexible nonmetallic conduit shall
be listed and marked for direct burial.
374.18 Cellular Metal Floor Raceways
Installations. New section.
ARTICLE 376 Metal Wireways
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376.56 Splices, Taps, and Power Distribution
Blocks.
(B)Power Distribution Blocks.
(1) Installation. Add- Power distribution
blocks installed on the line side of the service
equipment shall be listed for the purpose.
(5) Conductors. New section.
ARTICLE 384 Strut-Type Channel Raceway
384.10 Uses Permitted. The use of strut-type
channel raceways
shall be permitted in the following:
(1) Where exposed.
(2) In dry locations.
(3) In locations subject to corrosive vapors where
protected
by finishes judged suitable approved for the
condition.
(4) Where the voltage is 600 volts or less.
(5) (4) As power poles.
(6) (5) In Class I, Division 2 hazardous (classified)
locations
as permitted in 501.10(B)(3) Chapter 5.
(5)(6) As extensions of unbroken lengths through
walls, partitions, and floors where closure strips
are removable
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from either side and the portion within the wall,
partition, or floor remains covered.
(8) (7) Ferrous channel raceways and fittings
protected from corrosion solely by enamel shall
be permitted only indoors.
ARTICLE 386 Surface Metal Raceways
386.30 Securing and Supporting. Surface
metal raceways and associated fittings shall
be supported at intervals in accordance with
the manufacturer’s installation instructions.
386.120 Marking. New section.
ARTICLE 388 Surface Nonmetallic Raceways
388.30 Securing and Supporting. Surface
nonmetallic raceways and associated fittings
shall be supported at intervals in accordance
with the manufacturer’s installation
instructions.
388.120 Marking. Add- Each length of
surface metallic raceway shall be clearly and
durably identified as required in the first
sentence of 110.21(A).
ARTICLE 392 Cable Trays ARTICLE 392 Cable Trays
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392.10 Uses Permitted.
(H) Marking. Add- The danger marking(s) or
label(s) shall comply with 110.21(B).
Exception: Where not accessible (as applied
to equipment), in industrial establishments
where the conditions of maintenance and
supervision ensure that only qualified
persons service the installation, cable tray
system warning notices shall be located
where necessary for the installation to
ensure safe maintenance and repair.
392.20 Cable and Conductor Installation.
(A) Multiconductor Cables Rated Operating
at 600 Volts or Less. Multiconductor cables
rated operating at 600 volts or less shall be
permitted to be installed in the same cable
tray.
(B) Cables Rated Operating at Over 600
Volts. Cables operating at rated over 600
volts and those rated operating at 600 volts
or less installed in the same cable tray shall
comply with either of the following:
(1) The cables rated operating at over 600
volts are Type MC.
(2) The cables rated operating at over 600
volts are separated from the cables rated
392.20 Cable and Conductor Installation.
(A) Multiconductor Cables Rated Operating at
600 1000 Volts or Less. Multiconductor cables
operating at 600 1000 volts or less shall be
permitted to be installed in the same cable tray.
(B) Cables Operating at Over 1000 Volts. Cables
operating at over 600 1000 volts and those
operating at 600 1000 volts or less installed in the
same cable tray shall comply with either of the
following:
(1) The cables operating at over 600 1000 volts
are Type MC.
(2) The cables operating at over 600 1000 volts
are separated from the cables operating at 600
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operating at 600 volts or less by a solid fixed
barrier of a material compatible with the
cable tray.
1000 volts or less by a solid fixed barrier of a
material compatible with the cable tray.
392.22 Number of Conductors or Cables.
(A) Number of Multiconductor Cables, Rated
2000 Volts
or Less, in Cable Trays. The number of
multiconductor
cables, rated 2000 volts or less, permitted in a
single cable tray shall not exceed the
requirements of this section. The conductor sizes
apply to both aluminum and copper conductors.
Where dividers are used, fill calculations shall
apply to each divided section of the cable tray.
ARTICLE 393 Low-Voltage Suspended Ceiling
Power Distribution Systems. New Article.
ARTICLE 399 Outdoor Overhead Conductors
over 1000 Volts. Revised replacing all
references to 600 volts to 1000 volts.
Chapter 4 Equipment for General Use Chapter 4 Equipment for General Use
ARTICLE 400 Flexible Cords and Cables ARTICLE 400 Flexible Cords and Cables
400.4 Types. Flexible cords and flexible
cables shall conform to the description in
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Table 400.4. The use of flexible cords and
flexible cables other than those in Table
400.4 shall require permission by the
authority having jurisdiction. Types of
flexible cords and flexible cables other than
those listed in the table shall be the subject
of special investigation.
Table 400.4 Flexible Cords and Flexible Cables.
Revised.
Table 400.5(A)(1) Allowable Ampacity for
Flexible Cords and Flexible Cables. Revised.
400.6 Markings. Add- Required markings on
tags, cords, and cables shall also include the
maximum operating temperature of the
flexible cord or cable.
400.7 Uses Permitted.
(A) Uses.
(11) Between an existing receptacle outlet
and an inlet, where the inlet provides power
to an additional single receptacle outlet. The
wiring interconnecting the inlet to the single
receptacle outlet shall be a Chapter 3 wiring
method, including the flexible cord and
fitting, shall be a listed assembly specific for
this application.
400.8 400.12 Uses Not Permitted. Unless
specifically permitted in 400.7 400.10, flexible
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cords and cables, flexible cords, and power supply
cords shall not be used for the following:
(1) As a substitute for the fixed wiring of a
structure
(2) Where run through holes in walls, structural
ceilings,
suspended ceilings, dropped ceilings, or floors
(3) Where run through doorways, windows, or
similar
openings
(4) Where attached to building surfaces
Exception to (4): Flexible cord and flexible cable
shall be permitted to be attached to building
surfaces in accordance with the provisions of with
368.56(B).
(5) Where concealed by walls, floors, or ceilings or
located above suspended or dropped ceilings
Exception to (5): Flexible cord and flexible cable
shall be permitted if contained within an
enclosure for use in Other Spaces Used for
Environmental Air as permitted by 300.22(C)(3).
(6) Where installed in raceways, except as
otherwise permitted in this Code
(7) Where subject to physical damage
ARTICLE 404 Switches ARTICLE 404 Switches
404.2 Switch Connections.
(C) Switches Controlling Lighting Loads. New
section.
404.2 Switch Connections
(C) Switches Controlling Lighting Loads. The
grounded circuit conductor for the controlled
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lighting circuit shall be installed provided at the
location where switches control lighting loads,
that are supplied by a grounded general-purpose
branch circuit serving bathrooms, hallways,
stairways, or rooms suitable for human habitation
or occupancy as defined in the applicable building
code. Where multiple switch locations control the
same lighting load such that the entire floor area
of the room or space is visible from the single or
combined switch locations, the grounded circuit
conductor shall only be required at one location,
A grounded conductor shall not be required to be
installed at lighting switch locations under any of
the following conditions for other than the
following:
(1) Where conductors enter the box enclosing the
switch through a raceway, provided that the
raceway is large enough for all contained
conductors, including a grounded conductor.
(2) Where the box enclosing the switch is
accessible for the installation of an additional or
replacement cable without removing finish
materials.
(3) Where snap switches with integral enclosures
comply with 300.15(E).
(4) Where a switch does not serve a habitable
room or bathroom
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(5) Where multiple switch locations control the
same lighting load such that the entire floor area
of the room or space is visible from the single or
combined switch locations.
(6) (4) Where lighting in the area is controlled by
automatic means.
(7) (5) Where a switch controls a receptacle load.
The grounded conductor shall be extended to any
switch location as necessary and shall be
connected to switching devices that require line-
to-neutral voltage to operate the electronics of
the switch in the standby mode and shall meet
the requirements of 404.22.
Exception: The connection requirement shall
become effective on January 1, 2020. It shall not
apply to replacement or retrofit switches installed
prior to local adoption of 404.2(C) and where the
grounded conductor cannot be extended without
removing finish materials. The number of
electronic control switches on a branch circuit
shall not exceed five, and the number connected
to any feeder on the load side of a system or main
bonding jumper shall not exceed 25. For the
purpose of this exception, a neutral busbar, in
compliance with 200.2(B) and to which a main or
system bonding jumper is connected shall not
limit as to the number of electronic lighting
control switches connected.
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404.10 Mounting of Snap Switches.
(B) Box Mounted. Add- Screws used for the
purpose of attaching snap switch to a box
shall be of the type provided with a listed
snap switch, or shall be machine screws
having 32 threads per inch or part of listed
assemblies or systems, in accordance with
the manufacturer’s instructions.
404.16 Knife Switches Rated 600 to 1000
Volt Knife Switches. Auxiliary contacts of a
renewable or quick-break type or the
equivalent shall be provided on all knife
switches rated 600 to 1000 volts and
designed for use in breaking current over
200 amperes.
404.22 Electronic Lighting Control Switches. Add-
Exception: Electronic lighting control switches that
introduce current on the equipment grounding
conductor shall be permitted for applications
covered by 404.2(C), Exception. Electronic lighting
control switches that introduce current on the
equipment grounding conductor shall be listed
and marked for use in replacement or retrofit
applications only.
ARTICLE 406 Receptacles, Cord Connectors,
and Attachment Plugs (Caps)
ARTICLE 406 Receptacles, Cord Connectors, and
Attachment Plugs (Caps)
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406.3 Receptacle Rating and Type. Add-
(E) Controlled Receptacle Marking. New
section.
406.3 Receptacle Rating and Type.
(E) Controlled Receptacle Marking. All nonlocking
type, 125-volt, 15- and 20-ampere receptacles
that are controlled by an automatic control
device, or that incorporate control features that
remove power from the receptacle for the
purpose of energy management or building
automation, shall be permanently marked with
the symbol shown in Figure 406.4(E) and the word
“controlled”.
For receptacles controlled by an automatic
control device, the marking shall be located on
the receptacle face and visible after installation.
In both cases where a multiple receptacle device
is used, the required marking of the word
“controlled” and symbol shall denote which
contact device(s) are controlled.
Exception: The marking is shall not be required for
receptacles controlled by a wall switch that
provide the required room lighting outlets as
permitted by 210.70.
(F) Receptacles with USB Charger. New section.
406.4 General Installation Requirements.
(B) To Be Grounded. Receptacles and cord
connectors
that have equipment grounding conductor
contacts shall
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have those contacts connected to an equipment
grounding conductor.
Exception No. 1: Receptacles mounted on portable
and
vehicle-mounted generator sets and generators in
accordance with 250.34.
Exception No. 2: Replacement receptacles as
permitted by
406.4(D).
(D) Replacements. Replacement of receptacles
shall comply with 406.4(D)(1) through (D)(6), as
applicable.
(1) Grounding-Type Receptacles. Where a
grounding
means exists in the receptacle enclosure or an
equipment grounding conductor is installed in
accordance with 250.130(C), grounding-type
receptacles shall be used and shall be connected
to the equipment grounding conductor in
accordance with 406.4(C) or 250.130(C).
(2) Non–Grounding-Type Receptacles. Where
attachment to an equipment grounding
conductor does not exist in the receptacle
enclosure, the installation shall comply with
(D)(2)(a), (D)(2)(b), or (D)(2)(c).
(a) A non–grounding-type receptacle(s) shall be
permitted to be replaced with another non–
grounding-type receptacle(s).
(b) A non–grounding-type receptacle(s) shall be
permitted to be replaced with a ground-fault
circuit interrupter type of receptacle(s). These
receptacles or their coverplates shall be marked
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“No Equipment Ground.” An equipment
grounding conductor shall not be connected from
the ground-fault circuit interrupter-type
receptacle to any outlet supplied from the
ground-fault circuit-interrupter receptacle.
(c) A non–grounding-type receptacle(s) shall be
permitted to be replaced with a grounding-type
receptacle(s) where supplied through a ground-
fault circuit interrupter. Where grounding-type
receptacles are Grounding-type receptacles
supplied through the ground-fault circuit
interrupter, grounding-type receptacles or their
cover plates shall be marked “GFCI Protected”
and “No Equipment Ground,” visible after
installation. An equipment grounding conductor
shall not be connected between the grounding
type receptacles.
(3) Ground-Fault Circuit-Interrupters. Ground-
fault
circuit-interrupter protected receptacles shall be
provided where replacements are made at
receptacle outlets that are required to be so
protected elsewhere in this Code.
Exception: Where replacement of the receptacle
type is impracticable, such as where the outlet box
size will not permit the installation of the GFCI
receptacle shall be permitted to be replaced with
a new receptacle of the existing type, where GFCI
protection is provided and the receptacle is
marked “GFCI Protected” and “No Equipment
Ground,” in accordance with 406.4(D)(2)(a), (b), or
(c), applicable.
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(4) Arc-Fault Circuit-Interrupter Protection.
Where a
receptacle outlet is located in any areas specified
in 210.12(A) or (B), supplied by a branch circuit
that requires arc-fault circuit interrupter
protection as specified elsewhere in this Code, a
replacement receptacle at this outlet shall be one
of the following:
(1) A listed outlet branch circuit type arc-fault
circuit interrupter receptacle
(2) A receptacle protected by a listed outlet
branch circuit type arc-fault circuit interrupter
type receptacle
(3) A receptacle protected by a listed combination
type
arc-fault circuit interrupter type circuit breaker
This requirement becomes effective January 1,
2014.
Exception No. 1: Arc-fault circuit-interrupter
protection shall not be required where all of the
following apply:
(1) The replacement complies with
406.4(D)(2)(b).
(2) It is impracticable to provide an equipment
grounding conductor as provided by
250.130(C).
(3) A listed combination type arc-fault circuit-
interrupter circuit breaker is not
commercially available.
(4) GFCI/AFCI dual function receptacles are
not commercially available.
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Exception No. 2: Section 210.12(B), Exception shall
not apply to replacement of receptacles.
(5) Tamper-Resistant Receptacles. Listed tamper-
resistant receptacles shall be provided where
replacements are made at receptacle outlets that
are required to be tamper-resistant elsewhere in
this Code, except where a non-grounding
receptacle is replaced with another non-
grounding receptacle.
406.5 Receptacle Mounting. Receptacles
shall be mounted in identified boxes or
assemblies. The designed for the purpose,
and such boxes or assemblies shall be
securely fastened in place unless otherwise
permitted elsewhere in this Code. Screws
used for the purpose of attaching
receptacles to a box shall be of the type
provided with a listed receptacle, or shall be
machine screws having 32 threads per inch
or part of listed assemblies or systems, in
accordance with the manufacturer’s
instructions.
(E) Receptacles in Countertops and Similar
Work Surfaces in Dwelling Units.
Receptacles, unless listed as receptacle
assemblies for countertop applications, shall
not be installed in a face-up position in
countertops or similar work surfaces. Where
receptacle assemblies for countertop
applications are required to provide ground-
fault circuit-interrupter protection for
personnel in accordance with 210.8, such
406.5 Receptacle Mounting. Receptacles shall be
mounted in identified boxes or assemblies. The
boxes or assemblies shall be securely fastened in
place unless otherwise permitted elsewhere in
this Code. Screws used for the purpose of
attaching receptacles to a box shall be of the type
provided with a listed receptacle, or shall be
machine screws having 32 threads per inch or
part of listed assemblies or systems, in
accordance with the manufacturer’s instructions.
(E) Receptacles in Countertops and Similar Work
Surfaces. Receptacle assemblies for installation in
countertop surfaces shall be listed for countertop
applications. Receptacles, unless listed as
receptacle assemblies for countertop
applications, shall not be installed in a face-up
position in countertops or similar work surfaces.
Where receptacle assemblies for countertop
applications are required to provide ground-fault
circuit-interrupter protection for personnel in
accordance with 210.8, such assemblies shall be
permitted to be listed as GFCI receptacle
assemblies for countertop applications.
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assemblies shall be permitted to be listed as
GFCI receptacle assemblies for countertop
applications.
(F) Receptacles in Seating Areas and Other
Similar Surfaces. In seating areas or similar
surfaces, receptacles shall not be installed in
a face-up position unless the receptacle is
any of the following:
(1) Part of an assembly listed as a furniture
power distribution unit, if cord-and-plug-
connected
(2) Part of an assembly listed either as
household furnishings or as commercial
furnishings
(3) Listed either as a receptacle assembly for
countertop applications or as a GFCI
receptacle assembly for countertop
applications.
(4) Installed in a listed floor box
(F) (E) Exposed Terminals. Receptacles shall
be enclosed so that live wiring terminals are
not exposed to contact.
(G) (H) Voltage Between Adjacent Devices.
A receptacle shall not be grouped or ganged
in enclosures with other receptacles, snap
switches, or similar devices, unless they are
arranged so that the voltage between
adjacent devices does not exceed 300 volts,
or unless they are installed in enclosures
equipped with identified, securely installed
barriers between adjacent devices.
(F) Receptacles in Work Surfaces. New section
inserted.
(G) Receptacle Orientation. New section inserted.
(F) (H) Receptacles in Seating Areas and Other
Similar Surfaces. In seating areas or similar
surfaces, receptacles shall not be installed in a
face-up position unless the receptacle is any of
the following:
(1) Part of an assembly listed as a furniture power
distribution unit, if cord-and-plug-connected
(2) Part of an assembly listed either as household
furnishings or as commercial furnishings
(3) Listed either as a receptacle assembly for
countertop applications or as a GFCI receptacle
assembly for countertop applications.
(4) Installed in a listed floor box
(E) (I) Exposed Terminals. Receptacles shall be
enclosed so that live wiring terminals are not
exposed to contact.
(H) (J) Voltage Between Adjacent Devices. A
receptacle shall not be grouped or ganged in
enclosures with other receptacles, snap switches,
or similar devices, unless they are arranged so
that the voltage between adjacent devices does
not exceed 300 volts, or unless they are installed
in enclosures equipped with identified, securely
installed barriers between adjacent devices.
406.6 Receptacle Faceplates (Cover Plates).
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(D) Receptacle Faceplate (Cover Plates) with
Integral Night and/or USB Charger. New
subsection.
406.9 Receptacles in Damp or Wet
Locations.
(B) Wet Locations.
(1) 15- and 20-Ampere Receptacles in a Wet
Location.
15- and 20-ampere, 125- and 250-volt
receptacles installed in a wet location shall
have an enclosure that is weatherproof
whether or not the attachment plug cap is
inserted. An For other than one- or two-
family dwellings, an outlet box hood installed
for this purpose shall be listed and where
installed on an enclosure supported from
grade as described in 314.23(B) or as
described in 314.23(F) shall be identified as
“extra-duty.”
All 15- and 20-ampere, 125- and 250-volt
nonlocking-type
receptacles shall be listed weather-resistant
type.
Exception: 15- and 20-ampere, 125- through
250-volt receptacles installed in a wet
location and subject to routine high-pressure
spray washing shall be permitted to have an
enclosure that is weatherproof when the
attachment plug is removed.
406.9 Receptacles in Damp or Wet Locations.
(B) Wet Locations.
(1) 15- and 20-Ampere Receptacles in a Wet
Location.
15- and 20-ampere, 125- and 250-volt receptacles
installed in a wet location shall have an enclosure
that is weatherproof whether or not the
attachment plug cap is inserted. An outlet box
hood installed for this purpose shall be listed and
shall be identified as “extra-duty.” Other listed
products, enclosures, or assemblies providing
weatherproof protection that do not utilize outlet
box hood need not be marked “extra duty.”
All 15- and 20-ampere, 125- and 250-volt
nonlocking-type receptacles shall be listed
weather-resistant type.
Exception: 15- and 20-ampere, 125- through 250-
volt receptacles installed in a wet location and
subject to routine high-pressure spray washing
shall be permitted to have an enclosure that is
weatherproof when the attachment plug is
removed.
All 15- and 20-ampere 125- and 250-volt
nonlocking-type receptacles shall be listed and so
identified as the weather-resistant type.
406.12 Tamper-Resistant Receptacles in
Dwelling Units.
406.12 Tamper-Resistant Receptacles in Dwelling
Units.
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Tamper-resistant receptacles shall be
installed as specified in 406.12(A) through
(C).
(A) Dwelling Unit. In all areas specified in
210.52, all nonlocking-type 125-volt,
15- and 20-ampere receptacles shall
be listed tamper-resistant
receptacles.
(B) Guest Rooms and Guest Suites of
Hotel and Motels. All areas specified
in 210.52, all nonlocking-type 125-
volt, 15- and 20-ampere receptacles
shall be listed tamper-resistant
receptacles.
(C) Chile Care Facilities. In all child care
facilities, all nonlocking-type 125-volt,
15- and 20-ampere receptacles shall
be listed tamper-resistant
receptacles.
Exception to (A), (B), and (C): Receptacles in
the following locations shall not be required
to be tamper-resistant:
(1) Receptacles located more than 1.7 m
(51⁄2 E) above the floor.
(2) Receptacles that are part of a luminaire
or appliance.
(3) A single receptacle or a duplex receptacle
for two appliances located within dedicated
space for each appliance that, in normal use,
is not easily moved from one place to
another and that is cord-and-plug connected
All 15- and 20-ampere, 120- and 250-volt
nonlocking receptacles in the areas Tamper-
resistant receptacles shall be installed as specified
in 406.12(A) through (C). 406.12(1) through (7)
shall be listed tamper-resistant receptacles.
(1) Dwelling units in all areas specified
406.12(1) through in 210.52 and 550.13
(2) Guest rooms and guest suites of hotels
and motels
(3) Child Care facilities
(4) Preschools and elementary education
facilities
(5) Business offices, corridors, waiting rooms
and the like in clinics, medical and dental
offices and outpatient facilities.
(6) Subject of assembly occupancies described
in 518.2 to include places of waiting
transportation, gymnasiums, skating rinks,
and auditoriums
(7) Dormitories
(A) Dwelling Unit. In all areas specified in
210.52, all nonlocking-type 125-volt, 15-
and 20-ampere receptacles shall be listed
tamper-resistant receptacles.
(B) Guest Rooms and Guest Suites of Hotel
and Motels. All areas specified in 210.52,
all nonlocking-type 125-volt, 15- and 20-
ampere receptacles shall be listed tamper-
resistant receptacles.
(C) Chile Care Facilities. In all child care
facilities, all nonlocking-type 125-volt, 15-
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in accordance with 400.7(A)(6), (A)(7), or
(A)(8).
(4) Nongrounding receptacles used for
replacements as
permitted in 406.4(D)(2)(a).
and 20-ampere receptacles shall be listed
tamper-resistant receptacles.
Exception to (A), (B), and (C): Receptacles in the
following locations shall not be required to be
tamper-resistant:
(1) Receptacles located more than 1.7 m (51⁄2 E)
above the floor.
(2) Receptacles that are part of a luminaire or
appliance.
(3) A single receptacle or a duplex receptacle for
two appliances located within dedicated space for
each appliance that, in normal use, is not easily
moved from one place to another and that is cord-
and-plug connected
in accordance with 400.7(A)(6), (A)(7), or (A)(8).
(4) Nongrounding receptacles used for
replacements as
permitted in 406.4(D)(2)(a).
406.15 Dimmer-Controlled Receptacles.
New section.
ARTICLE 408 Switchboards, Switchgear, and
Panelboards
ARTICLE 408 Switchboards, Switchgear, and
Panelboards
408.1 Scope. This article covers
switchboards, switchgear, and panelboards.
It does not apply to equipment operating at
over 600 1000 volts, except as specifically
referenced elsewhere in the Code.
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408.3 Support and Arrangement of Busbars
and Conductors.
(E) Phase Bus Arrangement. New section.
408.3 Support and Arrangement of Busbars and
Conductors
(A)(2) Service Panelboards, Switchboards and
Switchgear. Add-
Exception: This requirement shall not apply to
service panelboards with provisions for more than
one service disconnect within a single enclosure
as permitted in 408.36, Exception 1, 2, and 3.
408.4 Field Identification Required
(B) Source of Supply. All switchboards,
switchgear, and panelboards supplied by a
feeder(s) in other than one- or two-family
dwellings shall be marked to indicate each
device or equipment where the power
originates.
408.4 Field Identification Required
(B) Source of Supply. All switchboards,
switchgear, and panelboards supplied by a
feeder(s) in other than one- or two-family
dwellings shall be permanently marked to
indicate each device or equipment where the
power originates. The label shall be permanently
affixed, of sufficient durability to withstand the
environment involved, and not handwritten.
408.55 Wire-Bending Space Within an
Enclosure Containing a Panelboard. Revised.
ARTICLE 409 Industrial Control Panels
409.22 Short-Circuit Current Rating.
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(A) Installation. An industrial control panel shall
not be installed where the available short-circuit
fault current exceeds its short-circuit current
rating as marked in accordance with 409.110(4).
(B) Documentation. If an industrial control panel
Is required to be marked with a short-circuit
current rating in accordance with 409.110(4), the
available short-circuit current at the industrial
control panel ad the date the short-circuit current
calculation was performed shall be documented
and made available to those to inspect the
installation.
409.110 Marking. Revise-
(3) Industrial control panels supplied by more
than one electrical power source where such that
more than one disconnecting means is required
to disconnect all circuits 50-volts or more power
within the control panel shall be marked to
indicate that more than one disconnect means is
required to de-energize the equipment. The
location of the means necessary to disconnect all
circuits 50-volts or more shall be documented and
available.
ARTICLE 410 Luminaires, Lampholders, and
Lamps
ARTICLE 410 Luminaires, Lampholders, and
Lamps
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410.10 Luminaires in Specific Locations.
Add-
(F) Luminaires Installed in or Under Roof
Decking. New section.
410.23 Covering of Combustible Material at
Outlet
Boxes. Any combustible wall or ceiling finish
exposed between the edge of a luminaire
canopy or pan and an outlet box having a
surface area of 1160 mm2 (180 in2) or more
shall be covered with noncombustible
material.
410.62 Cord-Connected Lampholders and
Luminaires
(C) Electric-Discharge and LED Luminaires.
(1) Cord-Connected Installation. A luminaire or a
listed
Assembly in compliance with any of the
conditions in (a) through (c) shall be permitted to
be cord connected provided the luminaire is
located directly below the outlet or busway, the
cord is not subject to strain or physical damage,
and the cord is visible over its entire length except
at termination. if the
following conditions apply:
(a) A luminaire shall be permitted to be
connected with a cord terminating in a
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grounding-type attachment plug or
busway plug.
(b) A luminaire assembly equipped with a
strain relief and canopy shall be permitted
to include a section of raceway not over
150 mm (6 in) in length and intended to
facilitate the connection to an outlet box
mounted above a suspended ceiling.
(c) Listed luminaires connected using listed
assemblies that incorporate manufactured
wiring system connectors in accordance
(1) The luminaire is located directly below the
outlet or
busway.
(2) The flexible cord meets all the following:
a. Is visible for its entire length outside the
luminaire
b. Is not subject to strain or physical damage
c. Is terminated in a grounding-type attachment
plug
cap or busway plug, or is a part of a listed
assembly
incorporating a manufactured wiring system
connector
in accordance with 604.6(C) shall be permitted to
be cord connected., or has a luminaire assembly
with a strain relief and canopy having a maximum
152 mm (6 in.) long section of raceway for
attachment to an outlet box above a suspended
ceiling
410.151 Installation.
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(B) Connected Load. Add-
The load calculation in 220.43(B) shall not be
required to limit the length of track on a
single branch circuit, and it shall not be
required to limit the number of luminaires
on a single track.
ARTICLE 411 Lighting Systems, Operating at
30 Volts or Less and Lighting Equipment
Connected to Class 2 Power Sources.
ARTICLE 411 Lighting Systems, Operating at 30
Volts or Less and Lighting Equipment Connected
to Class 2 Power Sources Low-Voltage Lighting.
411.1 Scope. This article covers lighting
systems operating at 30 volts or less and
their associated components. This article
also covers lighting equipment connected to
a Class 2 power source.
411.1 Scope. This article covers lighting systems
and their associated components operating at not
more than 30 volts ac or 60 volts dc. Where wet
contact is likely to occur, the limts are 15 volts ac
or 30 volts dc. or less and their associated
components. This article also covers lighting
equipment connected to a Class 2 power source.
411.3 Low-Voltage Lighting Systems.
(A) General. Lighting systems operating at 30
volts or less shall consist of an isolating
power supply, low-voltage luminaires, and
associated equipment that are all identified
for the use. The output circuits of the power
supply shall be rated for25 amperes and 30
volts (42.4 volts peak) maximum under all
load conditions.
411.3 Low-Voltage Lighting Systems. Low voltage
lighting systems shall
(A) General. Lighting systems operating at 30
volts or less shall consist of an isolating power
supply, low-voltage luminaires, and associated
equipment that are all identified for the use. The
output circuits of the power supply shall be rated
for25 amperes maximum and 30 volts (42.4 volts
peak) maximum under all load conditions.
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(B) Class 2. Listed Class 2 lighting equipment
shall be rated in conformance with Chapter
9, Table II(A) or Table II(B).
(B) Class 2. Listed Class 2 lighting equipment shall
be rated in conformance with Chapter 9, Table
II(A) or Table II(B).
411.3 411.4 Listing Required. Add- Class 2
power sources and lighting equipment
connected to Class2 power sources shall be
listed.
411.4 Listing Required. Lighting systems
operating at 30 volts or less shall comply with
411.4(A) or 411.4(B). Class 2 power sources and
lighting equipment connected to Class 2 power
sources shall be listed.
(A) Listed System. Low voltage lighting systems
Lighting systems operating at 30 volts or less shall
be listed as a complete system. The luminaires,
power supply, and luminaire fittings (including the
exposed bare conductors) of an exposed bare
conductor lighting system shall comply with
411.4(A) or 411.4(B) be listed for the use as part
of the same identified lighting system.
(B) Assembly of Listed Parts. A lighting system
assembled from the following listed parts shall be
permitted:
(1) Low-voltage luminaires
(2) Low-voltage luminaire Power supply
(3) Low-voltage luminaire fittings
(4) Cord (secondary circuit) for which the
luminaires and
power supply are listed for use
(5) (4) Suitably rated cord, cable, Cable,
conductors in conduit, or other fixed Chapter 3
wiring method for the secondary circuit
The luminaires, power supply, and luminaire
fittings
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(including the exposed bare conductors) of an
exposed bare conductor lighting system shall be
listed for use as part of the same identified
lighting system.
ARTICLE 422 Appliances ARTICLE 422 Appliances
422.5 Ground-Fault Circuit Interrupter
(GFCI) Protection. New section.
422.5 Ground-Fault Circuit-Interrupter (GFCI)
Protection for Personnel.
(A) General. Appliances identified in 422.5(A)(1)
through (5) rated 250 volts or less and 60
amperes or less, single- or 3-phase, shall be
provided with GFCI protection for personnel.
Multiple GFCI protective devices shall be
permitted but shall not be required.
(1) Automotive vacuum machines provided for
public use.
(2) Drinking water coolers.
(3) High-pressure spray washing machines- cord-
nd-plug connected.
(4) Tire inflation machines provided for public use.
(5) Vending machines.
(B) Types. New subsection.
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The device providing GFCI protection required in
this article shall be readily accessible.
422.6 Listing Required. New section.
422.10 Branch-Circuit Rating
(F)(3) Water Heaters and Steam Boilers.
Resistance-type Water heaters and steam boilers
employing resistance-type immersion electric
heating elements contained in an ASME-rated and
stamped vessel or listed instantaneous water
heaters shall be permitted to be subdivided into
circuits not exceeding 120 amperes and protected
at not more than 150 amperes as follows:
(1) Where contained in ASME-rated and stamped
vessels.
(2) Where included in listed instantaneous water
heaters.
(3) Where installed in low-pressure water heater
tanks od open-outlet water heater vessels.
422.11 Overcurrent Protection.
(F) Electric Heating Appliances Employing
Resistance-Type Heating Elements Rates
More Than 48 Amperes.
(3) Water Heaters and Steam Boilers.
Resistance-type immersion electric heating
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elements Water heaters and steam boilers
employing resistance-type immersion
electric heating elements contained in an
ASME-rated and stamped vessel or listed
instantaneous water heaters shall be
permitted to be subdivided into circuits not
exceeding 120 amperes and protected at not
more than 150 amperes as follows:
(1) Where contained in ASME-rated and
stamped vessels
(2) Where included in listed
instantaneous water heaters
(3) Where installed in low-pressure
water heater tanks or open-outlet
water heater vessels
422.18 Support of Ceiling-Suspended (Paddle)
Fans.
Ceiling-suspended (paddle) fans shall be
supported independently of an outlet box or by
one of the following:
(1) A listed outlet box or listed outlet box
systems identified for the use and installed
in accordance with 314.27(C).
(2) A listed outlet box system, a listed locking
support and mounting receptacle, and a
compatible factory installed attachment
fitting designed for support, identified for
the use, and installed in accordance with
314.27(E).
422.21 Covering of Combustible Material at
Outlet Boxes. New section inserted.
422.21 Covering of Combustible Material at
Outlet Boxes. Any combustible ceiling finish that
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is exposed between the edge of a ceiling-
suspended (paddle) fan canopy or pan and an
outlet box and that has a surface area of 1160
mm 2 (180 in2) or more shall be covered with
noncombustible material.
422.23 Tire Inflation and Automotive
Vacuum Machines. New section inserted.
422.30 General. A means shall be provided to
simultaneously disconnect each appliance from all
ungrounded conductors in accordance with the
following sections of Part III. If an appliance is
supplied by more than one branch-circuit or
feeder, these disconnecting means shall be
grouped and identified as being the multiple
disconnecting means for the appliance. Each
disconnecting means shall simultaneously
disconnect all underground conductors that it
controls.
422.31 Disconnection of Permanently
Connected Appliances.
(C) Motor-Operated Appliances Rated over
½ Horsepower. New section.
422.31 Disconnection of Permanently Connected
Appliances.
(A) Rated at Not over 300 Volt-Amperes or 1⁄8
Horsepower.
For permanently connected appliances rated at
not
over 300 volt-amperes or 1⁄8 hp, the branch-
circuit overcurrent device shall be permitted to
serve as the disconnecting means where the
switch or circuit breaker is within sight from the
appliance or is lockable n accordance with 110.25.
(C) Motor-Operated Appliances Rated over 1⁄8
Horsepower. The disconnecting means shall
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comply with 430.109 and 430.110. For
permanently connected motor-operated
appliances with motors, rated over 1/8 hp, the
disconnecting means shall be within sight from
the appliance or be capable of being locked in the
open position in compliance with 110.25. meet
422.31(C)(1) or (2).
(1) The branch-circuit switch or circuit breaker
shall be permitted to serve as the disconnecting
means where the switch or circuit breaker is
within sight from the appliance.
(2) The disconnecting means shall be installed
within sight of the appliance.
Exception: If an appliance of more than 1⁄8 hp is
provided
with a unit switch that complies with 422.34(A),
(B), (C), or (D), the switch or circuit breaker serving
as the other disconnecting means shall be
permitted to be out of sight from the appliance.
422.33 Disconnection of Cord-and-Plug-
Connected
or Attachment Fitting-Connected Appliances.
(A) Separable Connector or an Attachment Plug
(or Attachment Fitting) and Receptacle. For cord-
and-plug-(or attachment fitting-)connected
appliances, an accessible separable connector or
an accessible plug (or attachment fitting) and
receptacle combination shall be permitted to
serve as the disconnecting means. Where the
separable connector or plug and receptacle are
not accessible, cord-and-plug-connected or
attachment fitting-and-plug-connected appliances
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shall be provided with disconnecting means in
accordance with 422.31.
(B) Connection at the Rear Base of a Range. For
cord-and-plug-connected household electric
ranges, an attachment plug and receptacle
connection at the rear base of a range, accessible,
if it is accessible from the front by removal of a
drawer, shall meet be considered as meeting the
intent of 422.33(A).
422.51 Vending Machines. New section.
ARTICLE 424 Fixed Electric Space-Heating
Equipment
ARTICLE 424 Fixed Electric Space-Heating
Equipment
424.19 Disconnecting Means. Means shall
be provided to
simultaneously disconnect the heater, motor
controller(s), and supplementary overcurrent
protective device(s) of all fixed electric
space-heating equipment from all
ungrounded conductors. Where heating
equipment is supplied by more than one
source, feeder, or branch circuit, the
disconnecting means shall be grouped and
marked. The disconnecting means specified
in 424.19(A) and (B) shall have an ampere
rating not less than 125 percent of the total
load of the motors and the heaters, and shall
be lockable in accordance with 110.25. The
provision for locking or adding a lock to the
disconnecting means shall be installed on or
424.19 Disconnecting Means. Means shall be
provided to
simultaneously disconnect the heater, motor
controller(s), and supplementary overcurrent
protective device(s) of all fixed electric space-
heating equipment from all ungrounded
conductors. Where heating equipment is supplied
by more than one source, feeder, or branch
circuit, the disconnecting means shall be grouped
and identified as having multiple disconnecting
means. Each disconnecting means shall
simultaneously disconnect all ungrounded
conductors that it controls marked. The
disconnecting means specified in 424.19(A) and
(B) shall have an ampere rating not less than 125
percent of the total load of the motors and the
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at the switch or circuit breaker used as the
disconnecting means and shall remain in
place with or without the lock installed.
(A) Heating Equipment with Supplementary
Overcurrent
Protection. The disconnecting means for
fixed electric
space-heating equipment with
supplementary overcurrent protection shall
be within sight from the supplementary
overcurrent protective device(s), on the
supply side of these devices, if fuses, and, in
addition, shall comply with either
424.19(A)(1) or (A)(2).
(1) Heater Containing No Motor Rated over
1⁄8 Horsepower. The above disconnecting
means specified in or unit switches
complying with 424.19(C) shall be permitted
to serve as the required disconnecting
means for both the motor controller(s) and
heater under either of the following
conditions:
(1) The disconnecting means provided is also
within sight
from the motor controller(s) and the heater.
(2) The disconnecting means is lockable in
accordance with 110.25 provided is capable
of being
locked in the open (off) position.
(2) Heater Containing a Motor(s) Rated over
1⁄8 Horsepower. The above disconnecting
means shall be permitted to serve as the
heaters, and shall be lockable in accordance with
110.25.
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required disconnecting means for both the
motor controller(s) and heater under either
of the following conditions:
(1) Where the disconnecting means is in
sight from the
motor controller(s) and the heater and
complies with
Part IX of Article 430.
(2) Where a motor(s) of more than 1⁄8 hp
and the heater are provided with a single
unit switch that complies with
422.34(A), (B), (C), or (D), the disconnecting
means
shall be permitted to be out of sight from the
motor
controller.
(B) Heating Equipment Without
Supplementary Overcurrent Protection.
(1) Without Motor or with Motor Not over
1⁄8 Horsepower. For fixed electric space-
heating equipment without a motor rated
over 1⁄8 hp, the branch-circuit switch or
circuit breaker shall be permitted to serve as
the disconnecting means where the switch
or circuit breaker is within sight from the
heater or is lockable in accordance with
110.25 capable of being locked in the open
(off) position.
(2) Over 1⁄8 Horsepower. For motor-driven
electric space heating equipment with a
motor rated over 1⁄8 hp, a disconnecPng
means shall be located within sight from the
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motor controller or shall be permitted to
comply with the requirements in
424.19(A)(2).
(C) Unit Switch(es) as Disconnecting Means.
A unit
switch(es) with a marked “off” position that
is part of a
fixed heater and disconnects all ungrounded
conductors
shall be permitted as the disconnecting
means required
by this article where other means for
disconnection are
provided in the types of occupancies in
424.19(C)(1)
through (C)(4).
(1) Multifamily Dwellings. In multifamily
dwellings, the
other disconnecting means shall be within
the dwelling
unit, or on the same floor as the dwelling
unit in which the fixed heater is installed,
and shall also be permitted to control lamps
and appliances.
(2) Two-Family Dwellings. In two-family
dwellings, the
other disconnecting means shall be
permitted either inside or outside of the
dwelling unit in which the fixed heater is
installed. In this case, an individual switch or
circuit breaker for the dwelling unit shall be
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permitted and shall also be permitted to
control lamps and appliances.
(3) One-Family Dwellings. In one-family
dwellings, the service disconnecting means
shall be permitted to be the other
disconnecting means.
(4) Other Occupancies. In other occupancies,
the branch circuit switch or circuit breaker,
where readily accessible
for servicing of the fixed heater, shall be
permitted as the other disconnecting means.
424.34 Heating Cable Construction. Heating
cables shall
be furnished complete with Factory-assembled
nonheating leads of heating cables, if any, shall be
at least 2.1 m (7 ft) in length.
424.38 Area Restrictions.
(A) Shall Not Extend Extending Beyond the Room
or Area. Heating cables shall be permitted not
extend beyond the room or area in which they
originate.
(B) Uses Prohibited Not Permitted. Heating
cables shall not be installed in the following as
follows:
(1) In closets, other than as noted in 424.38(C)
(2) Over the top of walls where the wall intersects
the ceiling
(3) Over partitions that extend to the ceiling,
unless they
are isolated single runs of embedded cable
(4) Under or through walls
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(4) (5) Over cabinets whose clearance from the
ceiling is less than the minimum horizontal
dimension of the cabinet to the nearest cabinet
edge that is open to the room or area
(6) I tub and shower walls
(7) Under cabinets and similar built-ins having no
clearance to the floor
424.40 Splices. Embedded cables shall be spliced
only
where necessary and only by approved means,
and in no
case shall The length of the heating cable shall
only be altered using splices identified in the
manufacturer’s instructions be altered.
424.41 Ceiling Installation of Heating Cables on
Dry Board, in
Plaster, and on Concrete Ceilings.
(A) In Walls. Cables shall not be installed in walls
unless
it is necessary for an isolated single run of cable to
be
installed down a vertical surface to reach a
dropped ceiling.
(B) Adjacent Runs. Adjacent runs of heating cable
shall be installed in accordance with the
manufacturer’s instructions. cable not exceeding
9 watts/m (23⁄4 waQs/R) shall not be installed
less than 38 mm (11⁄2 in.) on centers.
(C) Surfaces to Be Applied. Heating cables shall be
applied
only to gypsum board, plaster lath, or other fire-
resistant material.
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With metal lath or other electrically conductive
surfaces,
a coat of plaster or other means employed in
accordance with the heating cable manufacturer’s
instructions shall be applied to completely
separate the metal lath or conductive surface
from the cable.
424.44 Installation of Cables in Concrete or
Poured
Masonry Floors.
(A) Watts per Linear Meter (Foot) Adjacent
Runs. Adjacent runs of heating cable shall be
installed in accordance with the
manufacturer’s instructions. Constant
wattage heating cables shall not exceed 54
watts per linear meter (161⁄2 waQs per
linear foot) of cable.
(B) Secured in Place. Cables shall be secured
in place by
nonmetallic frames or spreaders or other
approved means while the concrete or other
finish is applied.
Cables shall not be installed where they
bridge expansion
joints unless protected from expansion and
contraction.
(B) Spacings Between Heating Cable and
Metal Embedded in the Floor. Spacings shall
be maintained between the heating cable
and metal embedded in the floor, unless the
cable is a grounded metal-clad cable.
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(E) (C) Leads Protected. Leads shall be
protected where they leave the floor by rigid
metal conduit, intermediate metal conduit,
rigid nonmetallic conduit, electrical metallic
tubing, or by other approved means.
(F) (D) Bushings or Approved Fittings.
Bushings or approved
fittings shall be used where the leads emerge
within the
floor slab.
(G) (E) Ground-Fault Circuit-Interrupter
Protection.
Ground-fault circuit-interrupter protection
for personnel
shall be provided for cables installed in
electrically heated
floors of bathrooms and kitchens and in
hydromassage bathtub locations.
424.45 Installation of Cables Under Floor
Coverings. New section .
424.47 Label Provided by Manufacturer. New
section.
424.66 Installation. Revised.
(A) General. Duct heaters shall be installed in
accordance with the manufacturer’s
instructions in such a manner that operation
does not create a hazard to persons or
property. Furthermore, duct heaters shall be
located with respect to building construction
and other equipment so as to permit access
to the heater. Sufficient clearance shall be
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maintained to permit replacement of
controls and heating elements and for
adjusting and cleaning of controls and other
parts requiring such attention. See 110.26.
Working space about electrical enclosures
for resistance heating element-type duct
heaters that are mounted on duct systems
and contain equipment that requires
examination, adjustment, servicing, or
maintenance while energized shall comply
with 424.66(B).
(B)Limited Access. New section.
424.99 Installation Under Floor Covering.
(C) (B) Installation. Listed heating panels or panel
sets, if installed under floor covering, shall be
installed on floor surfaces that are smooth and
flat in accordance with the manufacturer’s
instructions and shall also comply with
424.99(C)(1) 424.99(B)(1) through (C)(5).
(4) Coverings. After heating panels or heating
panel sets
are installed and inspected, they shall be
permitted to be
covered by a floor covering that has been
identified by
the manufacturer as being suitable for the
installation.
(5) Fault GFCI Protection. Branch circuits A
device to open all ungrounded conductors
supplying the heating panels or heating
panel sets shall have ground-fault circuit-
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interrupter protection for personnel,
provided by the manufacturer, shall
function when a low- or high-resistance
line-to-line, line-to-grounded conductor,
or line-to-ground fault occurs, such as the
result of a penetration of the element or
element assembly.
(6) Grounding Braid od Sheath. New section.
Part X. Low-Voltage Fixed Electric Space-Heating
Equipment. New sections and subsections.
ARTICLE 425 Fixed Resistance and Electrode
Industrial Process Heating Equipment. New
sections and subsections.
ARTICLE 427
Fixed Electric Heating Equipment for Pipelines
and Vessels
427.27 Voltage Limitations. Unless protected by
groundfault circuit-interrupter protection for
personnel, The secondary winding of the isolation
transformer connected to the pipeline or vessel
being heated shall not have an output voltage
greater than 30 volts ac.
Where ground-fault circuit-interrupter protection
for
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personnel is provided, the voltage shall be
permitted to be greater than 30 but not more
than 80 volts.
Exception No. 1: In industrial establishments, the
isolation transformer connected to the pipeline or
vessel being heated shall be permitted to have an
output voltage greater than 30 but not more than
80 volts ac to ground when all of the following
conditions apply:
(1) Conditions of guarding, maintenance, and
supervision ensure that only qualified
persons have access to the installed
system.
(2) Ground-fault protection of the equipment
is provided.
Exception No. 2: In industrial establishments, the
isolation transformer connected to the pipeline or
vessel being heated shall be permitted to have an
output voltage not greater than 132 volts ac to
ground where all of the following conditions
apply:
(1) Conditions of guarding, maintenance and
supervision ensure that only qualified persons
service the installed systems.
(2) Ground-fault protection of equipment is
provided.
(3) The pipeline or vessel being heated is
completely enclosed in a grounded metal
enclosure.
(4) The transformer secondary connections to the
pipeline
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or vessel being heated are completely enclosed in
a grounded metal mesh or metal enclosure.
ARTICLE 430 Motors, Motor Circuits, and
Controllers
ARTICLE 430 Motors, Motor Circuits, and
Controllers
430.53 Several Motors and Loads on One Branch
Circuit.
(D) Single Motor Taps. Add-
(4) Conductors from the point of the tap from the
branch circuit to a listed manual motor controller
additionally marked “Suitable for Tap Conductor
Protection in Group Installations,” or to a branch-
circuit protective device, shall be permitted to
have an ampacity not less than one-third that of
the branch-circuit conductors. The conductors
from the controller to the motor shall have an
ampacity in accordance with 430.22. The
conductors from the point of tap to the
controller(s) shall (1) be suitably protected from
physical damage and enclosed either by an
enclosed controller or by a raceway and be not
more than 7.5 mm (25 ft) long or (2) have an
ampacity not less than that of the branch-circuit
conductors.
430.130 Branch-Circuit Short-Circuit and
Ground-Fault Protection for Single Motor
Circuits Containing . New section.
430.130 Branch-Circuit Short-Circuit and Ground-
Fault Protection for Single Motor Circuits
Containing Power Conversion Equipment.
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(A) Circuits Containing Power Conversion
Equipment. Add-
(4) Where an instantaneous trip circuit breaker or
semiconductor fuse are permitted in accordance
with the drive manufacturer’s instructions for use
as the branch-circuit short-circuit and ground-
fault protective device for listed power
conversion equipment, they shall be provided as
an integral part of a single listed assembly
incorporating both the protective device and
power conversion equipment.
430.131 Several Motors or Loads on One
Branch Circuit Including Power Conversion
Equipment. New section.
ARTICLE 440 Air-Conditioning and Refrigeration
Equipment.
440.9 Grounding and Bonding. New section.
440.10 Short-Circuit Current Rating. New section.
440.33 Motor-Compressor(s) With or Without
Additional Motor Loads. Conductors supplying
one or more motor-compressor(s) with or without
an additional motor load(s) shall have an
ampacity not less than the sum of each of the
following:
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(1) The sum of the rated load or branch-circuit
selection current, whichever is larger greater, of
all the motor-compressor{s}
(2) The sum of the full-load current rating of all
currents of the other motors plus
(3) 25 percent of the highest motor or motor-
compressor or full load current rating in the
group.
Exception No. 1: Where the circuitry is interlocked
so as
to prevent the starting and running of a second
motor compressor or group of motor-
compressors, the conductor size shall be
determined from the largest motor-compressor or
group of motor-compressors that is to be
operated at a given time.
Exception No. 2: The branch-circuit conductors for
room
air conditioners shall be in accordance with Part
VII of Article 440.
440.65 Leakage-Current Detector-Interrupter
(LCDI)
and Arc-Fault Circuit Interrupter (AFCI)
Protection Device. Single-phase cord-and-plug-
connected room air conditioners shall be
provided with one of the following factory-
installed devices factory-installed LCDI or AFCI
protection.
(1) Leakage-current detector-interrupter
(LCDI)]
(2) Arc-fault circuit interrupter (AFCI)
(3) Heat detecting circuit interrupter (HDCI)
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The LCDI or AFCI protection device shall be an
integral part of the attachment plug or be located
in the power supply cord within 300 mm (12 in.)
of the attachment plug.
ARTICLE 445 Generators ARTICLE 445 Generators
445.11 Marking. Each generator shall be
provided with a nameplate giving the
manufacturer’s name, the rated frequency,
power factor, number of phases if of
alternating current AC, the subtransient and
transient impedances, the rating in kilowatts
or kilovolt amperes, the normal volts and
amperes corresponding to the rating, rated
revolutions per minute, insulation system
class and the rated ambient temperature or
rated temperature rise, and time rating.
Nameplates for all stationary generators and
portable generators rated more than 15 kW
shall also give the power factor, the sub-
transient and transient impedances, the
insulation system class, and the time rating.
Marking shall be provided by the
manufacturer to indicate whether or not in
general neutral is bonded to the generator
frame. Where the bonding of a generator is
modified in the field, additional marking shall
be required to indicate whether the
445.11 Marking. Each generator shall be provided
with a nameplate giving the manufacturer’s
name, the rated frequency, number of phases if
AC, the rating in kilowatts or kilovolt amperes, the
power factor, the normal volts and amperes
corresponding to the rating, rated revolutions per
minute, and the rated ambient temperature or
rated temperature rise.
Nameplates or manufacturer’s instructions shall
provide the following information for all
stationary generators and portable generators
rated more than 15 kW: shall also give the power
factor, the sub-transient and transient
impedances, the insulation system class, and the
time rating.
(1) Subtransient, transient, synchronous, and
zero sequence reactances
(2) Power rating category.
(3) Insulation system class.
(4) Information if the generator is protected
against overload by inherent design, an
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generator neutral is bonded to the generator
frame.
overcurrent protective relay, circuit
breaker, or fuse
(5) Maximum short-circuit current for
inverter-based generators, in lieu of the
synchronous, subtransient, and transient
reactiances
Marking shall be provided by the manufacturer to
indicate whether or not in general neutral is
bonded to its the generator frame. Where the
bonding of a generator is modified in the field,
additional marking shall be required to indicate
whether the generator neutral is bonded to the
generator frame.
445.13 Ampacity of Conductors.
(A) General. The ampacity of the conductors from
the generator terminals to the first distribution
device(s) containing overcurrent protection shall
not be less than 115 percent of the nameplate
current rating of the generator. It shall be
permitted to size the neutral conductors in
accordance with 220.61. Conductors that must
carry ground-fault currents shall not be smaller
than required by 250.30(A). Neutral conductors of
dc generators that must carry ground-fault
currents shall not be smaller than the minimum
required size of the largest conductor.
Exception: Where the design and operation of the
generator prevent overloading, the ampacity of
the conductors shall not be less than 100 percent
of the nameplate current rating of the generator.
(B)Overcurrent Protection. New section.
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445.18 Disconnecting Means Required for
Generators.
Generators shall be equipped with
disconnect(s), lockable in the open position,
by means of which the generator and all
protective devices and control apparatus are
able to be disconnected entirely from the
circuits supplied by the generator except
where both of the following conditions
apply:
(1) Portable generators are cord- and
plug-connected, or
(2) Both or the following conditions
apply:
a. The driving means for the generator
can be readily shut down, is rendered
incapable of restarting, and is
lockable in the OFF position in
accordance with 110.25.
b. The generator is not arranged to
operate in parallel with another
generator or other source of voltage.
445.18 Disconnecting Means Required for
Generators and Shutdown of Prime Mover.
Revised with new subsections.
445.20 Ground-Fault Circuit-Interrupter
Protection for Receptacles on 15-kW or
Smaller Portable Generator. New section.
ARTICLE 450 Transformers and Transformer
Vaults (Including Secondary Ties)
ARTICLE 450 Transformers and Transformer
Vaults (Including Secondary Ties)
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450.3 Overcurrent Protection. This article
covers switchboards, switchgear, and
panelboards. It does not apply to equipment
operating at over 600 1000 volts, except as
specifically referenced elsewhere in the
Code.
450.5 Grounding Autotransformer.
Add- Exception: An auto transformer with a
wye configuration on its line side and a
zigzag configuration on its load side that
does not permit neutral or ground-fault
current to return over the line connection
shall be permitted on the loud side of a
system grounding connection. This exception
shall not apply to a connection made from a
high-resistance grounded system applied in
accordance with 250-30.
450.10 Grounding.
(A) Dry-Type Transformer Enclosures. New
Section.
(B) Other Metal Parts. Where grounded,
exposed non–current carrying metal parts of
transformer installations, including fences,
guards, and so forth, shall be grounded and
bonded under the conditions and in the
manner specified for electrical equipment
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and other exposed metal parts in Parts V, VI,
and VII of Article 250.
450.11 Marking. Revised.
(A) General. New section.
(B) Source Marking. New section.
ARTICLE 480 Storage Batteries ARTICLE 480 Storage Batteries
480.2 Definitions.
Cell. New definition.
Container. New definition.
Electrolyte. New definition.
Intercell Connector. New definition.
Nominal Voltage (Battery or Cell). New
definition.
Terminal. New definition.
480.3 Battery and Cell Terminations. New
section.
480.3 Battery and Cell Terminations Equipment.
New section inserted.
480.3 480.4 Battery and Cell Terminations.
(A) Dissimilar Metals Corrosion Prevention.
Where mating dissimilar metals, antioxidant
material suitable for the battery connection shall
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be used where recommended by the battery
manufacturer.
480.6 DC Disconnect Methods. New section.
480.8 Racks and Trays. Add-
(C) Accessibility. New subsection.
480.9 Battery Locations. Battery locations
shall conform
to 480.9(A), (B), and (C).
(A) Ventilation. Provisions appropriate to
the battery technology shall be made for
sufficient diffusion and ventilation of the
gases from the battery, if present, to prevent
the accumulation of an explosive mixture.
(B) Live Parts. Guarding of live parts shall
comply with
110.27.
(C) Working Space Spaces About Battery
Systems. Working space Spaces about the
battery systems shall comply with 110.26.
Working clearance space shall be measured
from the edge of the battery cabinet, racks,
or trays rack.
For battery racks, there shall be a minimum
clearance of 25 mm ( 1 in) between a cell
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container and any wall or structure on the
side not requiring access for maintenance.
Battery stands shall be permitted to contact
adjacent walls or structures, provided that
the battery shelf has a free air space for not
less than 90m percent of its length.
(D) Top Terminal Batteries. New section.
(E) Egress. New section.
(F) Piping in Battery Rooms. New section.
(G) Illumination. New section.
480.10 480.11 Vents.
(A) Vented Cells. Each vented cell shall be
equipped with
a flame arrester that is designed to prevent
destruction of the cell due to ignition of gases
within the cell by an external spark or flame
under normal operating conditions.
(B) Sealed Cells. Where the battery is constructed
such that an Sealed battery or cells shall be
equipped
with a pressure-release vent to prevent excessive
accumulation of pressure could occur within the
cell during operation, a pressure-release vent
shall be provided of gas pressure, or the battery
or cell shall be designed to prevent scatter of cell
parts in event of a cell explosion.
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ARTICLE 490 Equipment, Over 600 Volts,
Nominal
ARTICLE 490 Equipment, Over 600 Volts,
Nominal
490.21 Circuit-Interrupting Devices.
(B) Power Fuses and Fuseholders.
(6) Fuseholders. Fuseholders shall be
designed or installed so that they are de-
energized while a fuse is being replaced. A
field-applied permanent and legible sign, in
accordance with 110.21(B), shall be installed
immediately adjacent to the fuseholders and
shall be worded as follows:
DANGER- DISCONNECT CIRCUIT BEFORE
REPLACING FUSES.
Exception: Fuses and fuseholders designed to
permit fusereplacement by qualified persons
using identified equipment designed for the
purpose without de-energizing the
fuseholder shall be permitted.
490.25 Backfeed. New section.
490.47 Metal-Enclosed and Metal-Clad
Switchgear Used as Service Equipment. Add-
Where the compartment door or panel
provides access to parts that can only be
deenergized and visibly isolated by the
serving utility, the warning sign required by
490.35(A) shall include a notice that access is
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limited to the serving utility or is permitted
only following an authorization of the serving
utility.
490.48 Substation Design, Documentation,
and Required . New section.
ARTICLE 500 Hazardous (Classified)
Locations, Classes I, II, and III, Divisions 1
and 2
ARTICLE 500 Hazardous (Classified) Locations,
Classes I, II, and III, Divisions 1 and 2
500.2 Definitions.
Combustible Dust. Revised.
500.5 Classifications of Locations.
(A) Classifications of Locations General. Locations
shall be classified depending on the properties of
the flammable gas, flammable liquid-produced
vapor, combustible-liquid produced vapors,
combustible dusts, or fibers/flyings that may
could be present, and the likelihood that a
flammable or combustible concentration or
quantity is present. Where pyrophoric materials
are the only materials used or handled, these
locations shall not be classified. Each room,
section, or area shall be
considered individually in determining its
classification. Where pyrophoric materials are the
only materials used or handled, these locations
are outside the scope of this article.
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Refrigerant machinery rooms that contain
ammonia refrigeration systems and are equipped
with adequate mechanical ventilation that
operates continuously or is initiated by a
detection system at a concentration not
exceeding 150 ppm shall be permitted to be
classified as “unclassified” locations.
Rooms and areas containing ammonia
refrigeration systems that are equipped with
adequate mechanical ventilation may be classified
as “unclassified” locations.
500.8 Equipment.
(C) Marking
(4) Equipment Temperature. The marking
shall specify
the temperature class or operating
temperature at a 40°C
ambient temperature, or at the higher
ambient temperature if the equipment is
rated and marked for an ambient
temperature of greater than 40°C. For
equipment installed in a Class II, Division 1
location, the temperature class and
operating temperature shall be based on
operation of the equipment when blanketed
with the maximum amount of dust that can
accumulate on the equipment. The
temperature class, if provided, shall be
508.8 Equipment.
(F) Optical Fiber Cables. Where An optical fiber
cable contains conductors that are capable of
carrying current (composite optical fiber cable),
the optical fiber cable shall be installed in
accordance with the requirements of Article 500,
501, 502, or 503, as applicable.
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indicated using the temperature class (T
Codes) shown in Table 500.8(C). Equipment
for Class I and Class II shall be marked with
the maximum safe operating temperature,
as determined by simultaneous exposure to
the combinations of Class I and Class II
conditions.
Exception: Equipment of the non–heat-
producing type,
such as junction boxes, conduit, and fittings,
and equipment of the heat-producing type
having a maximum temperature not more
than 100°C shall not be required to have a
marked operating temperature or
temperature class.
ARTICLE 501 Class I Locations ARTICLE 501 Class I Locations
501.10 Wiring Methods
(A) Class I, Division 1
(1) General. Add-
(C) Optical fiber cable Types OFNP, OFCP,
OFNR, OFCR, OFNG, OFN, and OFC shall be
permitted to be installed in raceways in
accordance with 501.10(A). These optical
cables shall be sealed in accordance with
501.15.
501.10 Wiring Methods
(A) Class I, Division 1
(1) General.
(1) General.
(7) Optical fiber cable Types OFNP, OFCP, OFNR,
OFCR, OFNG, OFCG, OFN, and OFC shall be
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(e) Optical fiber cable Types OFNP, OFCP,
OFNR, OFCR, OFNG, OFCG, OFN, and OFC
shall be permitted to be installed in raceways
in accordance with 501.10(A). These optical
fiber cables shall be sealed in accordance
with 501.15.
(2) Connections. Add-
(1) Flexible fittings listed for the location, or
(2) Flexible cord in accordance with the
provisions of 501.140, terminated with cord
connectors listed for the location, or
(3) In industrial establishments with
restricted public access, where the
conditions of maintenance and supervision
ensure that only qualified persons service
the installation, for applications limited to
600 volts, nominal or less, and where
protected from damage by location or a
suitable guard, listed Type TC-ER-HL cable
with an overall jacket and a separate
equipment grounding conductor(s) in
accordance with 250.122 that is terminated
with fittings listed for the location.
(B) Class I, Division 2.
(1) General.
permitted to be installed in cable trays or any
other raceway in accordance with 501.10(B).
Optical fiber cables shall be sealed in accordance
with 501.15.
(2) Flexible Connections. Insert-
(3) Interlocked armor Type MC cable with listed
fitting.
Add- (7) For elevator use, an identified elevator
cable of Type EO, ETP, or ETT, shown under the
“use” column in Table 400.4 for “hazardous
(classified) locations” and terminated with listed
fittings.
(B) Class I, Division 2.
(1) General. In Class I, Division 2 locations, the
following wiring methods shall be permitted:
1. All wiring methods permitted in 501.10(A) Rigid
metal conduit (RMC) and intermediate metal
conduit (IMC) with listed threadless fittings.
(8) Cablebus
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(7) Optical fiber cable Types OFNP, OFCP,
OFNR, OFCR, OFNG, OFCG, OFN, and OFC
shall be permitted to be installed in cable
trays or any other raceway in accordance
with 501.10(B). Optical fiber cables shall be
sealed in accordance with 501.15.
(2) Flexible Connections. Insert-
(3) Interlocked armor Type MC cable with
listed fitting.
Add- (7) For elevator use, an identified
elevator cable of Type EO, ETP, or ETT,
shown under the “use” column in Table
400.4 for “hazardous (classified) locations”
and terminated with listed fittings.
501.15 Sealing and Drainage.
(1) Entering Enclosures. Revised.
(4) Class I, Division 1 Boundary. In each
conduit run leaving a Class I, Division 1
location A conduit seal shall be required in
each conduit run having a Division 1 location.
The sealing fitting shall be permitted to be
installed on either side of the boundary of
such location within 3.05 m (10 ft) of the
boundary and it shall be designed and
installed so as to minimize the amount of gas
or vapor within the portion of the conduit
installed in Division 1 location portion of the
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conduit from being that can be
communicated to the conduit beyond the
seal. The conduit run between the conduit
seal and the point at which the conduit
leaves the Division 1 location shall contain
Except for listed explosionproof reducers at
the conduit seal, there shall be no union,
coupling, box, or fitting except for the listed
explosionproof reducer at the conduit seal.
between the conduit seal and the point at
which the conduit leaves the Division 1
location.
Exception No. 1: Metal conduit that contains
no unions,
couplings, boxes, or fittings, that passes
completely through a Division 1 location with
not fittings installed within 300 mm (12 in.)
of either side of the boundary, and passes
completely through a Class I, Division 1
location with no fittings less than 300 mm
(12 in.) beyond each boundary, shall not
require a conduit seal if the termination
points of the unbroken conduit are located in
unclassified locations.
Exception No. 2: For underground conduit
installed in
accordance with 300.5 where the boundary is
below
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grade, the sealing fitting shall be permitted
to be installed
after the conduit emerges from below grade,
but there shall be no union, coupling, box, or
fitting, other than listed explosionproof
reducers at the sealing fitting, in the conduit
between the sealing fitting and the point at
which the conduit emerges from below
grade.
(2) Class I, Division 2 Boundary. A conduit
seal shall be required In each conduit run
passing leaving from a Class I, Division 2
location into an unclassified location. The
sealing fitting shall be permitted to be
installed on either side of the boundary of
such location boundary within 3.05 m (10 ft)
of the boundary and shall be designed and
installed to minimize the amount of gas or
vapor within the portion of the conduit
installed in the Division 2 location than can
be communicated beyond the seal. Rigid
metal conduit or threaded steel intermediate
metal conduit shall be used between the
sealing fitting and the point at which the
conduit leaves the Division 2 location, and a
threaded connection shall be used at the
sealing fitting. The conduit run between the
conduit seal and the point at which the
conduit leaves the Division 2 location shall
contain Except for listed reducers at the
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conduit seal, there shall be no union,
coupling, box, or other fitting except for
listed explosionproof reducer installed at the
conduit seal. fitting between the conduit seal
and the point at which the conduit leaves the
Division 2 location. Conduits shall be sealed
to minimize the amount of gas or vapor
within the Division 2 portion of the conduit
from being communicated to the conduit
beyond the seal. Such seals shall not be
required to be explosionproof but shall be
identified for the purpose of minimizing
passage of gases permitted under normal
operating conditions and shall be accessible.
Exception No. 1: Metal conduit that contains
no unions, couplings, boxes, or fittings, and
that passes completely through a Class I,
Division 2 location with no fittings less
installed within than 300 mm (12 in.) beyond
each boundary, shall not be required to be
sealed if the termination points of the
unbroken conduit are located in unclassified
locations.
Exception No. 2: Conduit systems terminating
at in an unclassified location where a wiring
method the metal conduit transitions is made
to cable tray, cablebus, ventilated busway,
Type MI cable, or to cable not installed in any
cable tray or raceway system shall not be
required to be sealed where passing from the
Class I, Division 2 location into the
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unclassified location under the following
conditions:
(1) The unclassified location shall be
outdoors or, if the conduit system is
all in one room., it shall be permitted
to be indoors.
(2) The conduits shall not terminate at an
enclosure containing an ignition
source in normal operation.
Exception No. 3: Conduit systems passing
from an enclosure or room that is
unclassified as a result of pressurization into
a Class I, Division 2 location shall not require
a seal at the boundary.
Exception No. 4: Segments of aboveground
conduit systems shall not be required to be
sealed where passing from a Class I, Division
2 location into an unclassified location if all
of the following conditions are met:
(1) No part of the conduit system segment
passes through a Class I, Division 1 location
where the conduit segment contains unions,
couplings, boxes, or fittings that are located
within 300 mm (12 in.) of the Class I, Division
1 location.
(2) The conduit system segment is located
entirely in outdoor locations.
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(3) The conduit system segment is not
directly connected to canned pumps, process
or service connections for flow, pressure, or
analysis measurement, and so forth, that
depend on a single compression seal,
diaphragm, or tube to prevent flammable or
combustible fluids from entering the conduit
system.
(4) The conduit system segment contains
only threaded metal conduit, unions,
couplings, conduit bodies, andfittings in the
unclassified location.
(5) The conduit system segment is sealed at
its entry to
each enclosure or fitting housing located in
the Division 2 location that contains
terminals, splices, or taps in Class I, Division 2
locations.
(C) Class I, Divisions 1 and 2. Seals installed
in Class I,
Division 1 and Division 2 locations shall
comply with
501.15(C)(1) through (C)(6).
Exception: Seals that are not required to be
explosion proof by 501.15(B)(2) or 504.70
shall be required to comply with 501.15(C).
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(1) Fittings. Enclosures for that are
connections or equipment shall be provided
with an integral sealing means for sealing, or
sealing fittings listed for the location shall be
used. Sealing fittings shall be listed for use
with one or more specific compounds and
shall be accessible.
(2) Compound. The compound shall provide
a seal against to minimize the passage of gas
or vapors through the seal sealing fitting and
shall not be affected by the surrounding
atmosphere or liquids. The melting point of
the compound and shall not have a melting
point of be less than 93°C (200°F).
(3) Thickness of Compounds. Except for
listed cable sealing fittings, The thickness of
the sealing compound installed in completed
seals, other than listed cable sealing fittings,
in a completed seal shall not be less than the
metric designator (trade size) of the sealing
fitting expressed in the units of
measurement employed; however, and in no
case shall the thickness of the compound be
less than 16 mm (5⁄8 in.).
(4) Splices and Taps. Splices and taps shall
not be made in fittings intended only for
sealing with compound, nor shall other
fittings in which splices or taps are made be
filled with compound.
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(5) Assemblies. An entire assembly shall be
identified for the location In an assembly
where the equipment that may produce arcs,
sparks, or high temperatures is located in a
compartment that is separate from the
compartment containing splices or taps, and
an integral seal is provided where
conductors pass from one compartment to
the other. In Division 1 locations, seals shall
be provided the entire assembly shall be
identified for the location. Seals in conduit
connecting connections to the compartment
containing splices or taps shall be provided in
Class I, Division 1 locations where required
by 501.15(A)(1)(2).
(6) Conductor or Optical Fiber Fill. The cross-
sectional area of the conductors or optical
fiber tubes (metallic or nonmetallic)
permitted in a seal shall not exceed 25
percent of the cross-sectional area of a rigid
metal conduit of the same trade size unless
the seal it is specifically identified for a
higher percentage of fill.
D) Cable Seals, Class I, Division 1. In Class I,
Division 1 locations, cable seals shall be
located according to501.15(D)(1) through
(D)(3).
(1) At Terminations. Cable shall be sealed
with sealing fittings that comply with
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501.15(C) at all terminations. The sealing
fitting shall comply with 501.15(C).
Multiconductor Type MC-HL cables with a
gas/vaportight continuous corrugated
metallic sheath and an overall jacket of
suitable polymeric material shall be sealed
with a listed fitting after removing the jacket
and any other covering have been removed
so that the sealing compound so surround
each individual insulated conductor in such a
manner as to minimize the passage of gases
and vapors.
Exception: Shielded cables and twisted pair
cables shall not require the removal of the
shielding material or separation of the
twisted pairs, provided the termination is
sealed by an approved means to minimize
the entrance of gases or vapors and prevent
propagation of flame into the cable core.
(2) Cables Capable of Transmitting Gases or
Vapors. Cables in conduit with a
gas/vaportight continuous sheath capable of
transmitting gases or vapors through the
cable core, installed in conduit shall be
sealed in the Class I, Division 1 location after
removing the jacket and any other coverings
have been removed so that the sealing
compound can will surround each individual
insulated conductor or optical fiber tube and
the outer jacket.
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Exception: Multiconductor cables with a
gas/vaportight continuous sheath capable of
transmitting gases or vapors through the
cable core shall be permitted to be
considered as a single conductor by sealing
the cable in the conduit within 450 mm (18
in.) of the enclosure and the cable end within
the enclosure by an approved means to
minimize the entrance of gases or vapors and
prevent the propagation of flame into the
cable core, or by other approved methods.
For shielded cables and twisted pair cables, It
shall not be required to remove the shielding
material or separate the twisted pairs of
shielded cables and twisted pair cables.
(3) Cables Incapable of Transmitting Gases
or Vapors. Each multiconductor cable
installed in conduit shall be considered as a
single conductor if the cable is incapable of
transmitting gases or vapors through the
cable core. These cables shall be sealed in
accordance with 501.15(A).
501.17 Process Sealing. Add-
(4) An add-on secondary seal marked
“secondary Seal” and rated for the pressure
and temperature conditions to which it will
be subjected upon failure of the single
process seal.
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501.105 Meters, Instruments, and Relays
(B) Class I, Division 2.
(6) Connections.
(1) A switch complying with 501.105(B)(1) is
provided so that the attachment plug is not
depended on to interrupt current.
Exception: The switch is not required if the
circuit is nonincendive field wiring.
501.125 Motors and Generators
(B) Class I, Division 2. Revised.
501.140 Flexible Cords, Class I, Divisions 1
and 2.
(A) Permitted Uses. Flexible cord shall be
permitted:
(1) For connection between portable lighting
equipment or other portable utilization
equipment and the fixed portion of their
supply circuit. The flexible cord shall be
attached to the utilization equipment with a
cord connector listed for the protection
technique of the equipment wiring
compartment. An attachment plug in
accordance with 501.140(B) shall be
employed.
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ARTICLE 502 Class II Locations ARTICLE 502 Class II Locations
502.10 Wiring Methods.
(A) Class ll, Division 1
(1) General. Add-
(4) Optical fiber cables Types OFNP, OFCP,
OFNR, OFCR, OFNG, OFCG, OFN, and OFC
shall be permitted to be installed in raceways
in accordance with 502.10(A). Optical fiber
cables shall be sealed in accordance with
502.15.
(2) Flexible Connections. Add-
(6) For elevator use, an identified elevator
cable of Type EO, ETP, or ETT, shown under
the “use” column in Table 400.4 for
“hazardous (classified) locations” and
terminated with listed dusttight fittings.
(3) Boxes and Fittings. New section.
(B) Class ll, Division 2.
(1) General. Add-
(8) Optical fiber cable Types OFNP, OFCP,
OFNR, OFCR, OFNG, OFCG, OFN, and OFC
shall be permitted to be installed in cable
trays or in any other raceway b accordance
502.10 Wiring Methods.
(A) Class ll, Division 1
(1) General. Add-
(5) In industrial establishments with restricted
public access, where the conditions of
maintenance and supervision ensure that only
qualified persons service the installation, listed
Type ITC-HL cable with a gas/vaportight
continuous corrugated metallic sheath, and an
overall jacket of suitable polymeric material, and
terminated with fittings listed for the application,
and installed in accordance with the provisions of
Article 727.
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with 502.10(B). Optical fiber cables shall be
sealed in accordance with 502.15.
502.125 Motor and Generators.
(B) Class II, Division 2. Add-
(4) Machines with sealed bearings, bearing
isolators, and seals.
ARTICLE 503
Class lll Locations
503.5 General. Equipment installed in Class
III locationsshall be able to function at full
rating without developing surface
temperatures high enough to cause
excessive dehydration or gradual
carbonization of accumulated fibers/flyings.
Organic material that is carbonized or
excessively dry is highly susceptible to
spontaneous ignition. The maximum surface
temperatures under operating conditions
shall not exceed 165°C (329°F) for equipment
that is not subject to overloading, and 120°C
(248°F) for equipment (such as motors or
power transformers) that may be
overloaded. In a Class lll, Division 1 location,
the operating temperature shall be the
temperature of the equipment when
blanketed with the maximum amount of
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dust (simulating fibers/flyings) that can
accumulate on the equipment.
503.10 Wiring Methods
(A) Class lll, Division 1.
(1) General.
(4) add- The cable shall be terminated with
listed fittings.
(3) Flexible Connections. Add-
(6) For elevator use, an identified elevator
cable of Type EO, ETP, or ETT, shown in the
“use” column in Table 400.4 for “hazardous
(classified) locations” and terminated with
listed dusttight fittings.
503.10 Wiring Methods
(A) Class lll, Division 1.
(1) General. Add-
(5) Cablebus.
ARTICLE 504
Intrinsically Safe Systems
504.10 Equipment Installation.
(C) Enclosures. New section.
(D) Simple Apparatus. New section.
504.10 Equipment Installation.
(A) Control Drawing. Intrinsically safe apparatus,
associated apparatus , and other equipment shall
be installed in accordance with the control
drawing(s).
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A simple apparatus, whether or not shown on the
control drawing(s), shall be permitted to be
installed provided the simple apparatus
Exception: A simple apparatus that does not
interconnect intrinsically safe circuits.
(D) Simple Apparatus. Simple apparatus shall
be permitted to be installed in ay
hazardous (classified) location in which the
maximum surface temperature of the
simple apparatus does not exceed the
ignition temperature of the flammable
gases or vapors, flammable liquids,
combustible dusts, or ignitable
fibers/flyers. For simple apparatus, The
maximum surface temperature can be
determined from the values of the output
power from the associated apparatus or
apparatus to which it is connected to
obtain the temperature class. The
temperature class can be determined by:
504.30 Separation of Intrinsically Safe
Circuit Conductors.
(A) From nonintrinsically Safe Circuit
Conductors
(2) Within Enclosures.
(3) Separation from conductors of
nonintrinsically safe circuits by use of an
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approved insulating partition that extends to
within 1.5 mm (0.0625 in.) of the enclosure
wall.
(C) From Grounded Metal. New section.
ARTICLE 505 Zone 0, 1, and 2 Locations ARTICLE 505 Zone 0, 1, and 2 Locations
505.5 Classifications of Locations.
(A) Classification of Locations. Locations
shall be classified depending on the
properties of the flammable vapors gases,
flammable liquid-produces vapors,
combustible liquid-produced vapors,
combustible dusts, and fibers/flyings ,
liquids, or gases that may be present and the
likelihood that a flammable or combustible
concentration or quantity is present. Where
pyrophoric materials are the only materials
used or handled, these locations shall not be
classified. Each room, section, or area shall
be considered individually in determining its
classification. Where pyrophoric materials
are the only materials used or handled, these
locations are outside the scope of this
article.
505.5 Classifications of Locations.
(A) Classification of Locations. Locations shall be
classified depending on the properties of the
flammable vapors gases, flammable liquid-
produces vapors, combustible liquid-produced
vapors, combustible dusts, and fibers/flyings that
could be present and the likelihood that a
flammable or combustible concentration or
quantity is present. Each room, section, or area
shall be considered individually in determining its
classification. Where pyrophoric materials are the
only materials used or handled, these locations
are outside the scope of this article.
Refrigerant machinery rooms that contain
ammonia refrigeration systems and are equipped
with adequate mechanical ventilation that
operates continuously or is initiated by a
detection system at a concentration not
exceeding 150 ppm shall be permitted to be
classified as “unclassified” locations.
505.7 Special Precaution.
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(F) Available Short-Circuit Current for Type
of Protection “e”. New section.
(F) Optical Fiber Cables. Where An optical fiber
cable
contains conductors that are capable of with or
without carrying current (composite optical fiber
cable), the optical fiber cable shall be installed to
address the associated fire hazard and sealed to
address the associated explosion hazard in
accordance with the requirements of Articles
505.15 and 505.16.
505.15 Wiring Methods.
(B) Class 1, Zone 1. Add-
(g) Intrinsic safety type of protection “ib”
shall be permitted using the wiring methods
specified in Article 504.
(h) Optical fiber cable Types OFNP, OFCP,
OFNR, OFCR, OFNG, OFCG, OFN, and OFC
shall be permitted to be installed in raceways
in accordance with 505.15(B). Optical fiber
cable shall be sealed in accordance with
505.16.
(i) In industrial establishments with
restricted public access, where the
conditions of maintenance and supervision
ensure that only qualified persons service
the installation, for applications limited to
505.15 Wiring Methods.
(A) Class I, Zone 0. In Class I, Zone 0 locations,
equipment protected by intrinsic safety “ia” and
equipment protected by encapsulation “ma” shall
be connected using intrinsically safe “ia” circuits
with only intrinsically safe wiring methods in
accordance with Article 504 shall be permitted.
(C) Class I, Zone 2. Add-
(9) Cablebus
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600 volts nominal or less, for cable diameters
25 mm (1 in.) or less, and where the cable is
not subject to physical damage, Type TC-ER-
HL cable listed for use in Class 1, Zone 1
locations, with an overall jacket and a
separate equipment grounding conductor(s)
in accordance with 250.122, and terminated
with fittings listed for the location, Type TC-
ER-HL cable shall be installed in accordance
with the provisions of Article 336, including
the restrictions of 336.10(7).
(C) Class 1, Zone 2.
(1) General. Add-
(h) Optical cable fiber of Types OFNP, OFCP,
OFNR, OFCR, PFNG, OFCG, OFN, and OFC
shall be permitted to be installed in cable
trays or any other raceway in accordance
with 505.15(C). Optical fiber cable shall be
sealed in accordance with 505.16.
(2) Flexible Connections. Add-
Exception: For elevator use, an identified
elevator cable of Type EO, ETP, or ETT,
shown under the “use” column in Table
400.4 for “hazardous (classified) locations”
that is terminated with listed connectors
that maintain the type of protection of the
terminal compartment, shall be permitted.
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505.17 Flexible Cords and Connections,
Class I, Zones 1 and 2. Revised.
Add- (B) Instrumentation Connections for
Zone 2. New section.
505.20 Equipment Requirements. Insert-
(D) Materials. New section.
505.26 Process Sealing. Add-
(4) An add-on secondary seal marked
“secondary seal” and rated for the pressure
and temperature conditions to which it will
be subjected upon failure of the single
process seal.
ARTICLE 506 Zone 20, 21, and 22 Locations
for Combustible Dusts or Ignitible
Fibers/Flyings
ARTICLE 506 Zone 20, 21, and 22 Locations for
Combustible Dusts or Ignitible Fibers/Flyings
506.2 Definitions.
Combustible Dust. Dust particles that are
500 microns or smaller (material passing a
U.S. No. 35 Standard Sieve as defined in
ASTM E 11-09, Standard Specifications for
Wire Cloth and Sieves for Testing Purposes)
and present a fire or explosion hazard when
dispersed and ignited in air. Any finely
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divided solid material that is 420 microns
(0.017 in.) or smaller in diameter (material
passing a U.S. No. 40 Standard Sieve) and
presents a fire or explosion hazard when
dispersed and ignited in air.
[499:3.3.3]
506.3 Other Articles. New section.
506.6 Material Groups. New section
inserted.
506.9 Equipment Requirements.
(C) Marking.
(1) Division Equipment.
(2) Temperature classification in accordance
with 506.9(D) Material group in accordance
with 506.6.
Add- (3) Maximum surface temperature in
accordance with 506.9(D), marked as a
temperature value in degrees C, preceded by
“T” and followed by the symbol “C”.
(2)Zone Equipment.
Insert- (4) Temperature classification
Maximum surface temperature in
accordance with 506.9(D), marked as a
506.9 Equipment Requirements.
(F) Optical Fiber Cables. Where An optical fiber
cable, with or without current-carrying
conductors
contains conductors that are capable of carrying
current
(composite optical fiber cable), the optical fiber
cable shall be installed to address the associated
explosion hazard in accordance with the
requirements of Articles 506.15 and 506.16.
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temperature value in degrees C, preceded by
“T” and followed by the symbol “C”.
Add- Exception: Associated apparatus NOT
suitable for installation in a hazardous
(classified) locations shall be required to be
marked only with 506.9(C)(2)(2), (3), and (5),
but BOTH the symbol AEx in 506.9(C)(2)(2)
and the symbol for the type of protection in
506.9(C)(2)(3) shall be enclosed within the
same square brackets: for example, [AEx iaD]
or or [AEx ia] 111C.
(D) Temperature Classifications. Equipment
shall bemarked to show the maximum
surface temperature referenced to a 40°C
ambient, or at the higher marked ambient
temperature if the equipment is rated and
marked for an ambient temperature if
greater than 400 C. For equipment installed
in a Zone 20 or Zone 21 location, the
operating temperature shall be based on
operation of the equipment when blanketed
with the maximum amount if dust (or with
dust-simulating fibers/flyings) that can
accumulate on the equipment. Electrical
equipment designed for use in the ambient
temperature range between −20°C and
+40°C shall require no additional ambient
temperature marking. Electrical equipment
that is designed for use in a range of ambient
temperatures other than −20°C and +40°C is
considered to be special; and the ambient
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temperature range shall then be marked on
the equipment, including either the symbol
“Ta” or “Tamb” together with the special
range of ambient temperatures. As an
example, such a marking might be “–30°C ≤
Ta ≤ +40°C.” Electrical equipment suitable for
ambient temperatures exceeding 40°C
(104°F) shall be marked with both the
maximum ambient temperature and the
operating temperature at that ambient
temperatures.
Table 506.9(C)(2)(3) Types of Protection
Designation. Revised.
506.15 Wiring Methods
(A) Zone 20.
(2) Add-
Exception: No. 1 MI cable and fittings listed
for Class II, Division 1 locations shall be
permitted to be used.
Exception No. 2: Equipment identified as
intrinsically safe “iaD” or “ia” shall be
permitted to be connected using the wiring
methods identified in 504.20.
(6) Add-
506.15 Wiring Methods
(C) Zone 22. Add-
(10) Cablebus
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Exception No. 1: Flexible conduit and flexible
conduit and cord fittings listed for Class II,
Division 1 locations shall be
permitted to be used.
Exception No. 2: For elevator use, an
identified elevator cable of Type EO, ETP, or
ETT, shown under the “use” column in Table
404.4 for “hazardous (classified) locations”
and terminated with listed connectors that
maintain the type of protection of the
terminal compartment shall be permitted.
Add- (7) Optical fiber cable Types OFNP,
OFCP, OFNR, OFCR, OFNG, OFCG, OFN, and
OFC shall be permitted to be installed in
raceways in accordance with 506.15(A).
Optical fiber cables shall be sealed in
accordance with 506.16.
(b) Zone 21. Add-
Exception: Equipment identified as
intrinsically safe “ibD” or “ib” shall be
permitted to be connected using the wiring
methods identified in 504.20.
(C) Zone 22. In Zone 22 locations, the
following wiring methods shall be permitted.
(1) All wiring methods permitted in
506.15(B).
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(2) Rigid metal conduit, intermediate metal
conduit, electrical metallic tubing, dusttight
wireways.
(3) Type MC or MI cable with listed
termination fittings.
(4) Type PLTC and Type PLTC-ER cable in
accordance with the provisions of Article
725, including installation in cable tray
systems. The cable shall be terminated with
listed fittings.
(5) Type ITC and Type ITC-ER cable as
permitted in 727.4
and terminated with listed fittings.
(6) Type MC, MI, MV, or TC, or TC-ER cable
installed in ladder, ventilated trough, or
ventilated channel cable trays in a single
layer, with a space not less than the larger
cable diameter between two adjacent
cables, shall be the wiring method employed.
Single-conductor Type MV cables shall be
shielded or metallic armored. The cable shall
be terminated with listed fittings.
(7) Nonincendive field wiring Intrinsic safety
type of protection “ic” shall be permitted
using any
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of the wiring methods permitted for
unclassified locations. Nonincendive field
wiring Intrinsic safety type of protection “ic”
systems shall be installed in accordance with
the control drawing(s). Simple apparatus, not
shown on the control drawing, shall be
permitted in a nonincendive field wiring
circuit of intrinsic safety type of protection
“ic”, provided the simple apparatus does not
interconnect the nonincendive field wiring
intrinsic safety type of protection “ic”circuit
to any other circuit.
Separation of nonincendive field wiring
intrinsic safety type of protection “ic”circuits
shall be in accordance with one of the
following:
a. Be in separate cables. Be in
multiconductor cables where the conductors
have insulation with a minimum thickness of
0.25 mm (0.01 in.)
Add- (9) Optical fiber cable Types OFNP,
OFCP, OFCR, OFNG, OFCG, OFN, and OFC
shall be permitted to be installed in cable
trays or any raceway in accordance with
506.15(C). Optical fiber cables shall be sealed
in accordance with 506.16.
506.20 Equipment Installation. Insert-
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(D) Material Group. New section.
506.25 Grounding and Bonding. Regardless
of the voltage of the electrical system,
grounding and bonding shall comply with
Article 250 and the requirements in506.25(A)
and (B).
ARTICLE 511 Commercial Garages, Repair and
Storage
511.3 Area Classification, General.
(C)Major Repair Garages, Major and Minor.
Where vehicles using Class I liquids or heavier-
than-air gaseous fuels (such as LPG) are repaired,
hazardous area classification guidance is found in
Table 511.2(C) flammable liquids having a flash
point below 38°C (100°F) such as gasoline, or
gaseous fuels such as natural gas, hydrogen, or
LPG, will not be dispensed, but repair activities
that involve the transfer of such fluids or gases
are performed, the classification rules in (1), (2),
and (3) shall apply.
(D) Repair Garages Major. Where vehicles using
lighter-than-air gaseous fuels (such as hydrogen
or natural gas) are repaired or stored, hazardous
area classification guidance is found in Table
511.3(C).
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ARTICLE 514 Motor Fuel Dispensing
Facilities
ARTICLE 514 Motor Fuel Dispensing Facilities
514.3 Classification of Locations.
(C) Motor Fuel Dispensing Stations to
Boatyards and Marinas. New section.
(D) Closed Construction. New section.
(E) Open Construction. New section.
514.3 Classification of Locations.
(B)(2) Compressed Natural Gas, Liquefied Natural
Gas, and Liquefied Petroleum Gas Areas.
Revised.
(B)(3) Fuel Storage. New subsection.
514.11 Circuit Disconnects.
(A) General Emergency Electrical Disconnects.
Fuel dispensing systems shall be provided with
one or more clearly identified emergency shutoff
devices or electrical disconnects. Such devices or
disconnects shall be installed in approved
locations but not more than 6 m (20 ft) or more
than 30 m (100 ft) from the fuel dispensing
devices that they serve. Emergency shutoff
devices or electrical disconnects shall disconnect
power to all dispensing devices.; to all remote
pumps serving the dispensing devices; to all
associated power, control, and signal circuits; and
to all other electrical equipment in the hazardous
(classified) locations surrounding the fuel
dispensing devices. When more than one
emergency shutoff or electrical disconnect is
provided, all devices shall be interconnected.
Resetting from an emergency shutoff condition
shall require manual intervention and the manner
of resetting shall be approved by the authority
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having jurisdiction [30A:6.7] Each circuit leading
to or through dispensing
equipment, including all associated power,
communications, data, and video circuits, and
equipment for remote pumping systems, shall be
provided with a clearly identified and readily
accessible switch or other approved means,
located remote from the dispensing devices, to
disconnect simultaneously from the source of
supply, all conductors of the circuits, including the
grounded conductor, if any. Single-pole breakers
utilizing handle ties shall not be permitted.
(B) Attended Self-Service Motor Fuel Dispensing
Facilities. At attended motor fuel dispensing
facilities, the devices or disconnected shall be
readily accessible to the attendant
Emergency controls as specified in 514.11(A) shall
be installed at a location acceptable to the
authority having jurisdiction, but controls shall
not be more than 30 m (100 ft) from dispensers.
[30A:6.7.1]
(C) Unattended Self-Service Motor Fuel
Dispensing Facilities. At unattended motor fuel
dispensing facilities, the devices or disconnects
shall be readily accessible to patrons and at least
one additional device or disconnect shall be
readily accessible to each group of dispensing
devices on an individual island Emergency
controls as specified in 514.11(A) shall be installed
at a location acceptable to the authority having
jurisdiction, but the control shall be more than 6
m (20 ft) but less than 30 m (100 ft) from the
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dispensers. Additional emergency controls shall
be installed on each group of dispensers or the
outdoor equipment used to control the
dispensers. Emergency controls shall shut off all
power to all dispensing equipment at the station.
Controls shall be manually reset only in a manner
approved by the authority having jurisdiction.
[30A:6.7.2]
ARTICLE 516 Spray Applications, Dipping,
Coating, and Printing Processes Using
Flammable or Combustible Materials
ARTICLE 516 Spray Applications, Dipping,
Coating, and Printing Processes Using Flammable
or Combustible Materials
516.1 Definitions.
Flash-Off Area: New definition.
Limited Finishing Workstation. New
definition.
Resin Application Area. New definition.
Spray Area. Revised.
Spray Booth. Revised.
Unenclosed Spray Area. New definition.
516.1 516.2 Definitions.
Limited Finishing Workstation. Revised.
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Membrane Enclosure. New definition
Outdoor Spray Area. New definition.
Resin Application Area. New definition.
Spray Area. Revised.
Spray Booth. Revised.
Unenclosed Spray Area. Revised.
516.3 Classification of Locations.
Classification is based on dangerous
quantities of flammable vapors, combustible
mists, residues, dusts, or deposits that are
present or might be present in quantities
sufficient to produce ignitable or explosive
mixtures, with air.
Insert- (A) Zone Classification of Locations.
New section.
(B)Class I, Division 1 or Class I, Zone 0
Locations. Add- (3) The interior of any ink
fountain, ink reservoir, or ink tank.
(C) Class I, Division 1; Class I, Zone 1; or
Class II, Division 1; or Zone 21 Locations.
Add- (7) For limited finishing workstations,
the area inside the curtains or partitions. See
Figure 516.3(D)(5).
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(D) Class I, Division 2: Class I, Zone 2; Class
II, Division 2; or Zone 22 Locations. The
following spaces shall be considered Class I,
Division 2, or Class I, Zone 2, or Class II,
Division 2; or Zone 22, as applicable.
(1) Open Spraying Unenclosed Spray
Processes. For open unenclosed spraying, all
space outside of but within 6 m (20 ft)
horizontally and 3 m (10 ft) vertically of the
Class I, Division 1 or Class I, Zone 1 location
as defined in 516.3(A), and not separated
from it by partitions. See Figure 516.3(C)(1).
[33:6.5.1]
(2) Closed-Top, Open-Face, and Open-Front
Spraying Spray Booths and Spray Rooms.
If spray application operations are conducted
within a closed-top, open-face, or open-front
booth or room, as shown in Figure
516.3(D)(2), any electrical wiring or
utilization equipment located outside of the
booth or room but within 915 mm (3 ft) of
any opening the boundaries designated as
Division 2 or Zone 2 in Figure 516.3(C)(2)
shall be suitable for Class I, Division 2; Class I,
Zone 2; Class II, Division 2 locations,
whichever is applicable. The Class I, Division
2, Class I, Zone 2; Class II,
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Division 2; Zone 22mlocations, shown in
Figure 516.3(C D)(2) shall extend from the
edges of the open face or open front of the
booth or room in accordance with the
following:
(3)Open-Top Spraying Spray Booths. For
spraying operations conducted within an
open top spray booth, the space 900 mm (3
ft) vertically above the booth and within 900
mm (3 ft) of other booth openings shall be
considered Class I, Division 2; Class I, Zone 2;
Class II, Division 2; or Zone 22. [33:6.5.3]
(4)Enclosed Spray Booths and Spray Rooms.
For spraying operations confined to an
enclosed spray booth or room, electrical
area classification shall be as follows: the
space within 900 mm (3 ft) in all directions
from any openings shall be considered Class
I, Division 2; or Class I, Zone 2; or Class II,
Division 2 as shown in Figure 516.3(C)(4).
[33:6.5.4]
(1) The area within 915 mm (3 ft) of any
opening shall be classified as Class I,
Division 2; Class I, Zone 2; Class II,
Division 2; or Zone 22 locations,
whichever is applicable, as shown in
Figure 516.3(D)(4)(1).
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(2) Where exhaust air is recirculated,
both of the following shall apply:
a. The interior of any recirculation path
from the secondary particulate filters up
to and including the air supply plenum
shall be classified as Class I, Division 2;
Class I, Zone 2; Class II, Division 2; or
Zone 22 locations, whichever is
applicable.
b. The interior of fresh air supply ducts
shall be unclassified.
(3) Where exhaust air is not recirculated,
the interior of fresh air supply ducts and
fresh air supply plenums shall be
unclassified.
(5) Dip Tanks and and Drain Boards-
Surrounding Space Limited Finishing
Workstation. New section.
(6) Dip Tanks and Drain Boards- Space
Above Floor Areas Adjacent to Open
Dipping and Coating Processes. New section.
(7) Enclosed Coating and Dipping
Operations. New section.
Figure 516.3(D)(5) Class I, Division 2; Class I,
Zone 2; Class II, Division 2; or Zone 22
Locations Adjacent to a Limited Finishing
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Workstation. [33:Figure 14.3.5.1]. New
figure.
Figure 516.3(D)(6)(b) Electrical Area
Classification for Open Dipping and Coating
Processes with Peripheral Vapor
Containment and Ventilation- Vapors
Confined to Process Equipment. [34:Figure
6.4(b)]. New figure.
Figure 516.3(D)(6)(c) Electrical Area
Classification for Open Dipping and Coating
Processes with Partial Peripheral Vapor
Containment and Ventilation- Vapors NOT
Confined to Process Equipment. [34:Figure
6.4(c)]. New figure.
Figure 516.3(D)(6)(d) Electrical Area
Classification for Open Dipping and Coating
Processes with Partial Peripheral Vapor
Containment and Ventilation- Vapors
Confined to Process Equipment. [34:Figure
6.4(d)]. New figure.
Figure 516.3(D)(6)(e) Electrical Area
Classification for a Typical Printing Process.
[34:Figure 6.4(c)]. New figure.
516.4 Wiring and Equipment in Class I
Locations
(C) Illumination. Revised.
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(F) Static Electric Discharges. New section.
Figure 516.3(D)(7) Electrical Area
Classification Around in Enclosed Dipping or
Coating Process. [34:Figure 6.5]. New figure.
Figure 516.4 Electrical Area Classification for
Class I Liquid Operations Around Open
Containers, Supply Containers, Waste
Containers, Spray Gun Cleaners, and solvent
Distillation Units [33: Figure 6.5.5.2] New figure.
PART II Open Containers
New part and sections.
Figure 516.4(C)(1) Example of a Luminaire
that is Mounted Outside of the Spray Area
and is Secured from Outside the Spray Area.
[34:Figure 6.6.1]. New figure.
Figure 516.4(C)(3) Example of a Luminaire
that is an Integral Part of the Spray Area
and is Serviced from Inside the Spray Area.
[34:Figure 6.6.3]. New figure.
PART III. Spray Application Processes
New part and sections.
Figure 516.5(D)(1) Electrical Area Classification
for Unenclosed Spray Areas [33: Figure 6.5.1]
New figure.
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Figure 516.5(D)(2) Class I, Division 2; Class I, Zone
2; Class II, Division 2; or Zone 22 Locations
Adjacent to a Closed Top, Open Face, or Open
Front Spray Booth or Room [33: Figure 6.5.2]
New figure.
Figure 516.5(D)(4) Class I, Division 2; Class I, Zone
2; Class II, Division 2; or Zone 22 Locations
Adjacent to an Enclosed Spray Booth or Spray
Room [33: Figure 6.5.4] New figure.
Figure 516.5(D)(5) Class I, Division 2; Class I, Zone
2; Class II, Division 2; or Zone 22 Locations
Adjacent to a Limited Finishing Workstation [33:
Figure 14.3.5.1] New figure.
Figure 516.6(C)(a) Example of a Luminaire that is
Mounted Outside of the Spray Area and is
Services from Outside the Spray Area [33: Figure
6.6.1] New figure.
Figure 516.6(C)(b) Example of a Luminaire that is
an Integral Part of the Spray Area and is Serviced
from Inside the Spray Area [33: Figure 6.6.3] New
figure.
516.10 Special Equipment.
A. Fixed Electrostatic Equipment.
(10) Other Than Nonincendive Equipment.
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(a) Conveyors, or hangers, and application
equipment shall be arranged so as to that a
minimum separation maintain a safe
distance of at least twice the sparking
distance is maintained between the
workpiece or material being sprayed
between goods being painted and
electrodes, electrostatic atomizing heads, or
charged conductors. Warnings defining this
safe distance shall be posted. [33:11.4.1]
(B) Electrostatic Hand-Spraying Equipment.
This section shall apply to any equipment
using electrostatically charged elements for
the atomization, charging, and/or
precipitation of flammable and combustible
materials for coatings on articles, or for
other similar purposes in which the charging
or atomizing device is handheld and or
manipulated during the spraying operation.
Electro-static hand-spraying equipment and
devices used in connection with paint-
spraying operations shall be of listed types
and shall comply with 516.10(B)(1) through
(B)(5).
(3) Handle. The handle of the spraying gun
shall be electrically connected to ground by a
conductive material metallic connection and
be constructed so that the operator in
normal operating position is in direct
intimate electrical contact with the grounded
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handle with a resistance of not more than 1
megohm to prevent buildup of a static
charge on the operator’s body. Signs
indicating the necessity for grounding other
persons entering the spray area shall be
conspicuously posted.
(4) Electrostatic Equipment. All electrically
conductive objects in the spraying area,
except those objects required by the process
to be at high voltage, shall be electrically
connected to ground with a resistance of not
more than 1 megohm adequately grounded.
This requirement shall apply to paint
containers, wash cans, and any other
electrical conductive objects or devices in
the area. The equipment shall carry a
prominent, permanently installed warning
regarding the necessity for this grounding
feature.
Figure 516.29(a) Electrical Area Classification for
Open Dipping and Coating Processes without
Vapor Containment or Ventilation [34; Figure
6.4(a)] New figure.
Figure 516.29(b) Electrical Area Classification for
Open Dipping and Coating Processes with
Peripheral Vapor Containment and Ventilation-
Vapors Confined to Process Equipment [34;
Figure 6.4(a)] New figure.
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Figure 516.29(c) Electrical Area Classification for
Open Dipping and Coating processes with partial
Peripheral Vapor Containment and Ventilation-
Vapors Not Confined to Process Equipment [34;
Figure 6.4(c)] New figure.
Figure 516.29(d) Electrical Area Classification for
a Typical Printing Process [34; Figure 6.4(d)] New
figure.
ARTICLE 517 Health Care Facilities ARTICLE 517 Health Care Facilities
517.2 Definitions.
Patient Care Space. New definition.
Patient Care Vicinity. New definition.
Wet Procedure Location. New definition.
517.2 Definitions.
Invasive Procedure. New definition.
Medical Office (Dental Office). New definition.
Patient Care Space. Revised.
517.14 Panelboard Bonding. The equipment
grounding terminal buses of the normal and
essential branch-circuit panelboards serving
the same individual patient care vicinity shall
be connected together with an insulated
continuous copper conductor not smaller
than 10 AWG. Where two or more
panelboards serving the same individual
patient care vicinity are served from
separate transfer switches on the essential
electrical emergency system, the equipment
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grounding terminal buses of those
panelboards shall be connected together
with an insulated continuous copper
conductor not smaller than 10 AWG. This
conductor shall be permitted to be broken in
order to terminate on the equipment
grounding terminal bus in each panelboard.
517.16 Receptacles with Insulated
Grounding Terminals.
All isolated ground receptacles shall not be
installed within a patient care vicinity
[99:6.3.2.2.7.1(B)] Receptacles with insulated
grounding terminals, as described in
250.146(D), shall not be permitted.
517.16 Receptacles with Insulated Grounding
Terminals.
(A) Inside of a Patient Care Vicinity. An All
isolated grounding receptacle shall not be
installed within a patient care vicinity
[99:6.3.2.2.7.1(B)].
(B) Outside of a Patient Care Vicinity. Isolated
ground receptacle(s) installed in patient care
spaces outside of a patient care vicinity(s) shall
comply with 517.16(B)(1) and (2).
(1) The grounding terminals of isolated ground
receptacles installed in branch circuits for patient
care spaces shall be connected to an insulated
equipment grounding conductor in accordance
with 250.146(D) in addition to the equipment
grounding conductor path required in 517.13(A).
The equipment grounding conductor connected
to the grounding terminals of isolated ground
receptacles in patient care spaces shall be clearly
identified along the equipment grounding
conductor’s entire length by green insulation with
one or more yellow stripes.
(3) The insulated grounding conductor
required in 517.13(B) shall be clearly
identified along its entire length by green
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insulation, with no yellow stripes, and shall
not be connected to the grounding
terminals of isolated ground receptacles
but shall be connected to the box of
enclosure indicted in 517.12(B)(1)(2) and
to non-current carrying conductive
surfaces of fixed electrical equipment
indicated in 517.13(B)(1)(3).
517.18 General Care Areas.
(A) Patient Bed Location. Each patient bed
location shall be supplied by at least two
branch circuits, one from the critical branch
emergency system and one from the normal
system. All branch circuits from the normal
system shall originate in the same
panelboard. The electrical receptacles or the
cover plate for the electrical receptacles
supplied from the critical branch shall have a
distinct color or marking so as to be readily
identifiable and shall also indicate the
panelboard and branch-circuit number
supplying them.
Branch circuits The branch circuit serving
patient bed locations shall not be part of a
multi-wire branch circuit.
Exception No. 1: Branch circuits serving only
special purpose outlets or receptacles, such
as portable X-ray outlets, shall not be
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required to be served from the same
distribution panel or panels.
Exception No. 2: Requirements of 517.18(A)
shall not apply to patient bed locations in
clinics, medical and dental offıces, and
outpatient facilities; psychiatric, substance
abuse, and rehabilitation hospitals; sleeping
rooms of nursing homes and limited care
facilities meeting the requirements of
517.10(B)(2).
Exception No. 3: A general care patient bed
location served from two separate transfer
switches on the critical branch emergency
system shall not be required to have circuits
from the normal system.
B) Patient Bed Location Receptacles. Each
patient bed location shall be provided with a
minimum of four eight receptacles. They
shall be permitted to be of the single,
duplex, or quadruplex type, or any
combination of the three. All receptacles,
whether four or more, shall be listed
“hospital grade” and shall be so identified.
The grounding terminal of each receptacle
shall be connected to an insulated copper
equipment grounding conductor sized in
accordance with Table 250.122.
(C) Designated General Care Pediatric
Locations. Receptacles located within the
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patient rooms, bathrooms, playrooms,
activity rooms of, and patient care areas of
designated pediatric locations units, other
than nurseries, shall be listed tamper
resistant or shall employ a listed tamper-
resistant cover.
517.19 Critical Care Areas.
(A) Patient Bed Location Branch Circuits.
Each patient bed location shall be supplied
by at least two branch circuits, one or more
from the emergency system critical branch
and one or more circuits from the normal
system. At least one branch circuit from the
emergency system shall supply an outlet(s)
only at that bed location. All branch circuits
from the normal system shall be from a
single panelboard. Emergency system Critical
branch receptacles shall be identified and
shall also indicate the panelboard and circuit
number supplying them.
The branch circuit serving patient bed
locations shall not be part of a multi-wire
branch circuit.
Exception No. 1: Branch circuits serving only
special purpose receptacles or equipment in
critical care areas spaces shall be permitted
to be served by other panelboards.
517.19 Critical Care Areas.
(A) Patient Bed Location Branch Circuits. Each
patient bed location shall be supplied by at least
two branch circuits, one or more from the critical
branch and one or more circuits from the normal
system. At least one branch circuit from the
emergency system shall supply an outlet(s) only at
that bed location.
The electrical receptacles or the cover plates for
the electrical receptacles supplied from the life
safety and critical branches shall have a distinct
color or marking so as to be readily identifiable.
[99:6.4.2.2.6.2(C)]
All branch circuits from the normal system shall
be from a single panelboard. Critical branch
receptacles shall be identified and shall also
indicate the panelboard and circuit number
supplying them. The branch circuit serving patient
bed locations shall not be part of a multi-wire
branch circuit.
Exception No. 1: Branch circuits serving only
special purpose receptacles or equipment in
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Exception No. 2: Critical care locations spaces
served from two separate critical branch
transfer switches on the emergency system
shall not be required to have circuits from the
normal system.
(B) Patient Bed Location Receptacles.
(1) Minimum Number and Supply. Each
patient bed location shall be provided with a
minimum of six 14 receptacles, at least one
of which shall be connected to either of the
following:
(1) The normal system branch circuit
required in 517.19(A)
(2) An emergency system A critical branch
circuit supplied by a different transfer switch
than the other receptacles at the same
patient bed location.
critical care (Category 1) spaces shall be permitted
to be served by other panelboards.
Exception No. 2: Critical care spaces served from
two separate critical (Category 1) branch transfer
switches shall not be required to have circuits
from the normal system.
(C) Operating Room Receptacles. New section.
517.29 Essential Electrical Systems for Hospitals
and Other Health Care Facilities. New section and
subsection.
517.30 Essential Electrical Systems for
Hospitals.
(B) General.
(1) Separate Systems Branches. Essential
electrical systems for hospitals shall be
517.30 Essential Electrical Systems for Hospitals
Sources of Power. Revised.
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comprised of two three separate systems
branches capable of supplying a limited
amount of lighting and power service that is
considered essential for life safety and
effective hospital operation during the time
the normal electrical service is interrupted
for any reason. The three branches are life
safety, critical, and equipment. These two
systems shall be the emergency system and
the equipment system.
(4)(2) Transfer Switches. The number of
transfer switches to be used shall be based
on reliability, design, and load
considerations. Each branch of the
emergency essential electrical system and
each equipment system shall have one or
more transfer switches. One transfer switch
and downstream distribution system shall be
permitted to serve one or more branches or
systems in a facility with a maximum
demand on the essential electrical system of
150 kVA.
(C) Wiring Requirements.
(1) Separation from Other Circuits. The life
safety branch and critical branch of the
emergency essential electrical system shall
be kept entirely independent of all other
wiring and equipment and shall not enter the
same raceways, boxes, or cabinets with each
other or other wiring. Where general care
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locations are served from two separate
transfer switches on the emergency essential
electrical system in accordance with
517.18(A), Exception No. 3, the general care
circuits from the two separate systems shall
be kept independent of each other.
Where critical care locations are served from
two separate transfer switches on the
emergency essential electrical system in
accordance with 517.19(A), Exception No. 2,
the critical care circuits from the two
separate systems shall be kept independent
of each other. Wiring of the life safety
branch and the critical branch shall be
permitted to occupy the same raceways,
boxes, or cabinets of other circuits not part
of the branch where
such wiring complies with one of the
following:
(1) Is in transfer equipment enclosures
(2) Is in exit or emergency luminaires
supplied from two sources
(3) Is in a common junction box attached to
exit or emergency luminaires supplied from
two sources
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(4) Is for two or more emergency circuits
supplied from the same branch and same
transfer switch
The wiring of the equipment system branch
shall be permitted to occupy the same
raceways, boxes, or cabinets of other circuits
that are not part of the emergency system.
(4) Mechanical Protection of the
Emergency System. The wiring of the
life safety and critical branches
emergency systems in hospitals shall
be mechanically protected. Where
installed as branch circuits in patient
care spaces areas, the shall comply
with the installation requirements of
517.13(A) and (B). The following
wiring methods shall be permitted:
(1) Nonflexible metal raceways, Type MI
cable, Type RTRC marked with the suffix -
XW, or Schedule 80 PVC conduit.
Nonmetallic raceways shall not be used for
branch circuits that supply patient care
areas.
(D) Capacity of Systems. The essential
electrical system to be served by each
system and branch. Feeders shall have
adequate the capacity and rating to meet the
maximum demand likely to be produced by
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the connected load for the operation of all
functions and equipment shall be sized in
accordance with 215.2 and Part III of Article
220 Articles 215 and 220. The generator
set(s) shall have sufficient capacity and
proper rating to meet the demand produced
by the load of the essential electrical
system(s) at any given time. Demand
calculations for sizing of the generator set(s)
shall be based on any of the following:
(1) Prudent demand factors and historical
data
(2) Connected load
(3) Feeder calculation procedures described
in Article 220
(4) Any combination of the above
The sizing requirements in 700.4 and 701.4
shall notapply to hospital generator set(s).
(E) Receptacle Identification. The cover
plates for the electrical receptacles or the
electrical receptacles themselves supplied
from the emergency essential electrical
system shall have a distinctive color or
marking so as to be readily identifiable.
[99:4.4.2.2.4.2(B) 99:6.4.2.2.6.2(C)]
(F) Feeders from Alternate Power Sources.
New section.
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(G) Coordination. New section.
517.31 Emergency System Branches
Requiring Automatic Connection. Those
functions of patient care depending on
lighting or appliances that are connected to
the emergency essential electrical system
shall be divided into two mandatory
branches: the life safety branch and the
critical branch, described in 517.32 and
517.33.
The life safety and critical branches of the
emergency system shall be installed and
connected to the alternate power source so
that all functions supplied by these branches
specified herein here shall for the emergency
system shall be automatically restored to
operation within 10 seconds after
interruption of the normal source.
[99:4.4.2.2.2.1, 4.4.3.1 99:6.4.3.1]
517.31 Branches Requiring Automatic
Connection Requirements for the Essential
Electrical Systems. Revised.
517.32 Life Safety Branch. No function other
than those listed in 517.32(A) through (H)
shall be connected to the life safety branch.
The life safety branch of the emergency
essential electrical system shall supply power
for the following lighting, receptacles, and
equipment.
(F) Generator Set Accessories. Generator set
accessories as required for generator
517.32 571.33 Life Safety Branch. No function
other than
Add-
(C)(2) Alarm and alerting systems (other than fire
alarm systems) shall be connected to the life
safety branch or critical branch. [99:6.4.2.2.3.3]
(E) Generator Set and Transfer Switch Location.
Generator set locations as follows:
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performance. Loads dedicated to a specific
generator, including the fuel transfer
pump(s), ventilation fans, electrically
operated louvers, controls, cooling system,
and other generator accessories essential for
generator operation, shall be connected to
the life safety branch or to the output
terminals of the generator with overcurrent
protective devices.
(1) Task illumination
(2) battery charger for emergency battery-
powered lighting unit(s)
(3) Select receptacles at the generator set
location and essential electrical system transfer
switch locations. [99:6.4.2.2.3.2(4)]
517.33 Critical Branch.
(A) Task Illumination and Selected
Receptacles. The critical branch of the
emergency essential electrical system shall
supply power for task illumination, fixed
equipment, selected receptacles, and special
power circuits serving the following areas
and functions related to patient care:
517.34 Equipment System Connection to
Alternate Power Source. The equipment
system shall be installed and connected to
the alternate power source such that the
equipment described in 517.34(A) is
automatically restored to operation at
appropriate time-lag intervals following the
energizing of the emergency essential
electrical system. Its arrangement shall also
provide for the subsequent connection of
equipment described in 517.34(B).
[99:4.4.2.2.3.2]
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(A) Equipment for Delayed Automatic
Connection. Add-
(8) Supply return, exhaust ventilating
systems and/or air-conditioning systems
serving telephone equipment rooms and
closets and data equipment rooms and
closets.
517.35 Sources of Power
(E) Location of Essential Electrical System
Components.
Careful consideration shall be given to the
location of the spaces housing the
components of the essential electrical
system to minimize interruptions caused by
natural forces common to the area (e.g.,
storms, floods, earthquakes, or hazards
created by adjoining structures or activities).
Consideration shall also be given to the
possible interruption of normal electrical
services resulting from similar causes as well
as possible disruption of normal electrical
service due to internal wiring and equipment
failures. Consideration shall be given to the
physical separation of the main feeders of
the alternate source from the main feeders
of the normal electrical source to prevent
possible simultaneous interruption.
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517.41 Essential Electrical Systems.
(E) Receptacle Identification. The cover
plates for the
electrical receptacles or the electrical
receptacles themselves supplied from the
emergency electrical system shall have a
distinctive color or marking so as to be
readily identifiable. [99:4.5.2.2.4.2]
Nonlocking type, 125-volt, 15- and 20-
ampere receptacles shall have an illuminated
face or an indicator light to indicate that
there is power to the receptacle.
517.45 Essential Electrical Systems for Other
Health Care Facilities.
(A) Essential Electrical Distribution. If required by
the governing body, the essential electrical
distribution system for basic care (Category 3)
patient care spaces shall be comprised of an
alternate power system capable of supplying a
limited amount of lighting and power service for
the orderly cessation of procedures during a time
normal power service is interrupted. The essential
electrical distribution system shall be a battery or
generator system.
(D) General Care (Category 2) Patient Care
Spaces
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Power Systems. Where general care (Category 2)
patient carespaces are present, the essential
electrical distribution systems shall be as
described in 517.40 through 517.45.
(E) Power Systems. If required, alternate
power sources acceptable to the
governing body shall comply with the
requirements of NFPA 99-2015, Health
Care Facilities Code. Battery systems shall
be installed in accordance with the
requirements of Article 700, and generator
systems shall be as described in 517.30
through 517.35.
ARTICLE 520 Theaters, Audience Areas of
Motion Picture and Television Studios,
Performance Areas, and Similar Locations
ARTICLE 520 Theaters, Audience Areas of Motion
Picture and Television Studios, Performance
Areas, and Similar Locations
520.1 Definitions.
Stage Equipment. New definition.
Stage Lighting Hoist. New definition.
Stage Switchboard. New definition.
520.21 General. New section.
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520.26 Type if Switchboard. Add-
(D) Constant Power. New section.
520.40 Stage Lighting Hoist. New section.
520.53 Construction. Add-
(B) Neutral Terminal. Section inserted.
(C) Single-Pole Separable Connectors. Section
inserted.
(D) Supply Feed-Throughs. Section inserted.
520.54 Supply Conductors.
(B) Conductor Sizing. Section inserted.
(G) Protection of Supply Conductors and
Connectors. Section inserted.
(J) Supply Neutral Conductor. Revised.
520.62 Portable Power Distribution Units.
(F) Single-Conductor Feeders. New section.
520.68 Conductor Type.
(C) Overcurrent Protection. New section.
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520.74 Pilot Lights Required. New section.
520.68 Conductors for Portables. Add-
(3) Luminaire Supply Cords. New section.
ARTICLE 545 Manufactured Buildings
545.5 Supply Conductors. Provisions shall be
made to route the service-entrance,
underground services conductors, service-
lateral, feeder, or branch-circuit supply to
the service or building disconnecting means
conductors.
ARTICLE 550 Mobile Homes, Manufactured
Homes, and Mobile Home Parks
ARTICLE 550 Mobile Homes, Manufactured
Homes, and Mobile Home Parks
550.13 Receptacle Outlets.
(B) Ground-Fault Circuit Interrupters (GFCI). All
125-volt, single-phase,15- and 20-ampere
receptacle outlets installed in the locations
specified in 550.13(B)(1) trough (5) shall have
GFCI protection for personnel.
(1) Outdoors, including
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outdoors, in compartments accessible from
outside the unit, or in
(2) Bathrooms, including receptacles in
luminaires, shall have GFCI protection. GFCI
protection shall be provided for receptacle outlets
serving countertops in
(3) Kitchens, where receptacles are installed to
serve countertop surfaces
(4) Sinks, where receptacles are installed and
receptacle outlets located within 1.8 m (6 ft) of
the outer edge of the sink
(5) Dishwashers
a wet bar sink. The exceptions in 210.8(A) shall
be permitted.
Feeders supplying branch circuits shall be
permitted to be protected by a ground-fault
circuit-interrupter in lieu of the provision for such
interrupters specified herein.
550.15 Wiring Methods and Materials.
(H) Under-Chassis Wiring (Exposed to
Weather). Where outdoor or under-chassis
line-voltage (120 volts, nominal, or higher)
wiring is exposed to moisture or physical
damage, it shall be protected by a rigid metal
conduit or raceway approved for use in wet
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locations or where subject to physical
damage. Intermediate metal conduit, except
as provided in (1) or (2). The conductors shall
be suitable for wet locations.
(1) Where closely routed against frames and
equipment enclosures, reinforced
thermosetting resin conduit
(RTRC) listed for aboveground use, Type MI
cable, electrical metallic tubing, or rigid
polyvinyl chloride conduit (PVC) shall be
permitted.
(2) Where extending vertically from a direct-
burial depth of at least 457 mm (18 in.)
below grade and terminated to a factory-
installed conduit or enclosure, Schedule 80
PVC or RTRC listed for exposure to physical
damage.
ARTICLE 551 Recreational Vehicles and
Recreational Vehicle Parks
551.4 General Requirements. Add-
(C) Labels. New section.
551.30 Generator Installations.
E) Supply Conductors. The supply
conductors from the engine generator to the
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first termination on the vehicle shall be of
the stranded type and be installed in listed
flexible conduit or listed liquid tight flexible
conduit. The point of first termination shall
be in one of the following:
(1) Panelboard
(2) Junction box with a blank cover
(3) Junction box with a receptacle
(4) Enclosed transfer switch
(5) Receptacle assembly listed in conjunction
with the Generator
The panelboard, enclosed transfer switch, or
junction box with a receptacle shall be
installed within the vehicle’s interior and
within 450 mm (18 in.) of the point of entry
of the supply conductor into the vehicle.
compartment wall but not inside the
compartment. If the generator is below the
floor level and not in a compartment, the
panelboard or junction box with receptacle
shall be installed within the vehicle interior
within 450 mm (18 in.) of the point of entry
into the vehicle. A junction box with a blank
cover shall be mounted on the compartment
wall and shall be permitted inside or outside
the compartment; to A receptacle assembly
listed in conjunction with the generator shall
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be mounted in accordance with its listing. If
the generator is below floor level and not in
a compartment, the junction box with blank
cover shall be mounted either to any part of
the generator supporting structure (but not
to the generator); or to the vehicle floor on
the outside of the vehicle; or within 450 mm
(18 in.) of the any point of entry of the
supply conductors into the vehicle. A
receptacle assembly listed in conjunction
with the generator shall be mounted in
accordance with its listing. directly above the
generator on either the inside or outside of
the floor surface. Overcurrent protection in
accordance with 240.4 shall be provided for
supply conductors as an integral part of a
listed generator or shall be located within
450 mm (18 in.) of their point of entry into
the vehicle.
552.41 Receptacle Outlets Required.
(B) Location.
(1) Adjacent to countertops in the kitchen [at
least one on each side of the sink if
countertops are on each side and are 300
mm (12 in.) or over in width and depth
(3) Adjacent to countertop spaces of 300 mm
(12 in.) or more in width and depth that
cannot be reached from a receptacle
required in 551.41(B)(1) by a cord of 1.8 m (6
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ft) without crossing a traffic area, cooking
appliance, or sink
Add- (4) Rooftop decks that are accessible
from inside the RV shall have at least one
receptacle installed within the perimeter of
the rooftop deck. The receptacle shall not be
located more than 1.2 m (4 ft) above the
balcony, deck, or porch surface. The
receptacle shall comply with the
requirements of 406.9(B) for wet locations.
(D) Face-Up Position. A receptacle shall not
be installed in a face-up position in any
countertop or similar horizontal surface
surfaces within the living area.
551.42 Branch Circuits Required.
(C) Two to Five 15- or 20-Ampere Circuits.
Revised.
Exception No. 1: Additional 15- or 20-ampere
circuits shall be permitted where a listed
energy management system rated at 30-
ampere maximum is employed within the
system.
Exception No.2: Six 15- or 20-ampere circuits
shall be permitted without employing an
energy management system, provided that
the added sixth circuit serves only the power
converter; and the combined load of all six
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circuits does not exceed the allowable load
that was designed for use by the original five
circuits.
551.45 Distribution Panelboard.
551.46 Means for Connecting to Power
Supply
(D) Labeling at Electrical Entrance. Each
recreational vehicle shall have a safety label
with the signal word WARNING in minimum
6-mm (1/4-in.) high letters and text in
minimum 3-mm (1/8-in) high letters on a
contrasting background. The safety label
shall be permanently affixed to the exterior
skin, at or near the point of entrance of the
power-supply cord(s), and shall read, using
one of the following warnings, as
appropriate:a label 75 mm× 45 mm (3 in. ×
13⁄4 in.) minimum size, made of etched,
metal-stamped, or embossed brass, stainless
steel, or anodized or alclad aluminum not
less than 0.51 mm (0.020 in.) thick, or other
suitable material [e.g., 0.13 mm (0.005 in.)
thick plastic laminate] that reads, as
appropriate, either
WARNING
THIS CONNECTION IS FOR 110–125-VOLT AC,
60 HZ, ____ AMPERE SUPPLY.
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or
THIS CONNECTION IS FOR 208Y/120-VOLT or
120/240-VOLT AC, 3-POLE, 4-WIRE,
60 HZ, ______ AMPERE SUPPLY.
DO NOT EXCEED CIRCUIT RATING.
EXCEEDING THE CIRCUIT RATING MAY
CAUSE A FIRE AND RESULT IN
DEATH OF SERIOUS INJURY
The correct ampere rating shall be marked in
the blank space.
551.47 Wiring Methods.
(Q) Prewiring for Air-Conditioning
Installation.
(3) A safety label with the signal word
WARNING in minimum 6-mm (1/4-in.) high
letters and body text in minimum 3-mm
(1/8-in) high letters on a contrasting
background conforming to 551.46(D) shall
be affixed placed on or adjacent to the
junction box and shall read as follows:
WARNING
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AIR-CONDITIONING CIRCUIT.
THIS CONNECTION IS FOR AIR
CONDITIONERS
RATED 110–125-VOLT AC, 60 HZ,
___ AMPERES MAXIMUM.
DO NOT EXCEED CIRCUIT RATING.
EXCEEDING THE CIRCUIT RATING MAY
CAUSE A FIRE AND RESULT IN DEATH
OR SERIOUS INJURY
An ampere rating, not to exceed 80 percent
of the circuit rating, shall be legibly marked
in the blank space.
(R) Prewiring for Generator Installation.
(4) A safety label with the signal word
WARNING in minimum 6-mm (1/4-in.) high
letters and body text in minimum 3-mm
(1/8-in) high letters on a contrasting
background label conforming to 551.46(D)
shall be affixed placed on the cover of each
junction box containing incomplete circuitry
and shall read, using one of the following
warnings, as appropriate:
WARNING
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GENERATOR
ONLY INSTALL A GENERATOR LISTED
SPECIFICALLY FOR RV USE
HAVING OVERCURRENT PROTECTION
RATED 110-125-VOLT AC,
60 HZ, ______ AMPERES MAXIMUM.
or
GENERATOR
ONLY INSTALL A GENERATOR LISTED
SPECIFICALLY FOR RV USE
HAVING OVERCURRENT PROTECTION
RATED 120-240-VOLT AC,
60 HZ, _______ AMPERES MAXIMUM.
The correct ampere rating shall be legibly
marked in the
blank space.
(S) Prewiring for Other Circuits.
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(3) A safety label with the signal word
WARNING in minimum 6-mm (1/4-in.) high
letters and body text in minimum 3-mm
(1/8-in) high letters on a contrasting
background label conforming to 551.46(D)
shall be affixed placed on or adjacent to the
junction box or device listed for the purpose
and shall read as follows:
WARNING
THIS CONNECTION IS FOR _____
RATED_____
VOLT AC, 60 HZ, _____ AMPERES
MAXIMUM.
DO NOT EXCEED CIRCUIT RATING.
EXCEEDING THE CIRCUIT RATING MAY
CAUSE A FIRE AND RESULT IN DEATH OR
SERIOUS INJURY
An ampere rating not to exceed 80 percent
of the circuit rating shall be legibly marked in
the blank space.
551.53 Luminaires and Other Equipment .
(A) General. Any combustible wall or ceiling
finish exposed between the edge of a canopy
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or pan of a luminaire or ceiling suspended
(paddle) fan canopy, or pan and the outlet
box, shall be covered with noncombustible
material or a material identified for the
purpose.
551.71 Type Receptacles Provided. Every
recreational vehicle site with electrical
supply shall be equipped with at least one
20-ampere, 125-volt receptacle. A minimum
of 20 percent of all recreational vehicle sites,
with electrical supply, shall each be equipped
with a 50-ampere, 125/250-volt receptacle
conforming to the configuration as identified
in Figure 551.46(C). Every recreational
vehicle site equipped with a 50-ampere
receptacle shall also be equipped with a 30-
ampere, 125-volt receptacle conforming to
Figure 551.46 (C)(1).These electrical supplies
shall be permitted to include additional
receptacles that have configurations in
accordance with 551.81. A minimum of 70
percent of all recreational vehicle sites with
electrical supply shall each be equipped with
a 30-ampere, 125-volt receptacle conforming
to Figure 551.46(C). This supply shall be
permitted to include additional receptacle
configurations conforming to 551.81. The
remainder of all recreational vehicle sites
with electrical supply shall be equipped with
one or more of the receptacle configurations
conforming to 551.81. Dedicated tent sites
with a 15- or 20-ampere electrical supply
551.71 Type Receptacles Provided. Revised.
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shall be permitted to be excluded when
determining the percentage of recreational
vehicle sites with 30- or 50-ampere
receptacles.
Additional receptacles shall be permitted for
the connection of electrical equipment
outside the recreational vehicle within the
recreational vehicle park.
All 125-volt, single-phase, 15- and 20-ampere
receptacles shall have listed ground-fault
circuit-interrupter protection for personnel.
551.72 Distribution System. Revised.
Add-
(A) Systems. New section inserted.
(B) Three-Phase Systems. New section
inserted.
551.75 Grounding. Add-
(B) Grounding Electrode. New section.
ARTICLE 552 Park Trailers
552.5 Labels. New section.
552.42 Branch-Circuit Protection. New section
and subsections.
552.46 Branch Circuits.
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(A) Two to Five 15- or 20-Ampere Circuits. Two to
five
15- or 20-ampere circuits to supply lights,
receptacle outlets, and fixed appliances shall be
permitted. Such park trailers shall be equipped
with a distribution panelboard rated at 120 volts
maximum with a 30-ampere rated main power
supply assembly. Not more than two 120-volt
thermostatically controlled
appliances (i.e., air conditioner and water heater)
shall
be installed in such systems unless appliance
isolation switching, energy management systems,
or similar methods are used.
Exception No. 1: Additional 15- or 20-ampere
circuits shall be permitted where a listed energy
management system rated at 30 amperes
maximum is employed within the system.
Exception No. 2: Six 15- or 20-ampere circuits shall
be permitted without employing an energy
management system, provided that the added
sixth circuit serves only the power converter, and
the combined load of all six circuits does not
exceed the allowable load that was designed for
use by the original five circuits.
(I) Nonmetallic Box Without Cable Clamps.
Nonmetallic sheathed cables shall be supported
within 200 mm (8 in.) of a nonmetallic outlet box
without cable clamps. Where wiring devices with
integral enclosures are employed with a loop of
extra cable to permit future replacement of the
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device, the cable loop shall be considered as an
integral portion of the device.
Exception: Where wiring devices with integral
enclosures
are employed with a loop of extra cable to permit
future
replacement of the device, the cable loop shall be
considered as an integral portion of the device.
(O) Method of Connecting Expandable Units.
Revised, Add-
(2) Direct Wires Connected. New section.
(Q) Prewiring for Other Circuits. New section.
552.52 Switches. Add-
(C) Location. New section.
ARTICLE 590
Temporary Installations
590.4 General.
(I) Termination(s) at Devices. Flexible cords
and cables entering enclosures containing
devices requiring termination shall be
secured to the box with fittings listed for
connecting flexible cords and cables to boxes
designed for the purpose.
(J) Support. Cable assemblies and flexible
cords and cables shall be supported in place
590.4 General.
(B) Feeders. Revised.
(C) Branch Circuits. Revised.
(G) Splices. Revised.
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at intervals that ensure that they will be
protected from physical damage. Support
shall be in the form of staples, cable ties,
straps, or similar type fittings installed so as
not to cause damage. Cable assemblies and
flexible cords and cables installed as branch
circuits or feeders shall not be installed on
the floor or on the ground. Extension cords
shall not be required to comply with 590.4(J).
Vegetation shall not be used for support of
overhead spans of branch circuits or feeders.
Exception: For holiday lighting in accordance
with 590.3(B), where the conductors or
cables are arranged with strain relief devices,
tension take-up devices, or other approved
means to avoid damage from the movement
of the live vegetation, trees shall be
permitted to be used for support of overhead
spans of branch-circuit conductors or cables.
590.6 Ground-Fault Protection for
Personnel.
(A)(1) Receptacle Outlets Not Part of
Permanent Wiring.
All 125-volt, single-phase, 15-, 20-, and 30-
ampere receptacle outlets that are not a part
of the permanent wiring of the building or
structure and that are in use by personnel
shall have ground-fault circuit-interrupter
590.6 Ground-Fault Protection for Personnel.
(B)(2) SPGFCI Protection. New section.
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protection for personnel. Listed cord sets or
devices incorporating listed ground-fault
circuit-interrupter protection for personnel
identified for portable use shall be
permitted.
ARTICLE 600 Electric Signs and Outline
Lighting
ARTICLE 600 Electric Signs and Outline Lighting
600.2 Definitions.
Photovoltaic (PV) Powered Signs. New definition.
600.4 Markings
(E) Section Signs Installation Instructions.
Section All signs, outline lighting, skeleton
tubing systems, and retrofit kits shall be
marked to indicate that field-wiring and
installation instructions are required.
Exception: Portable, cord-connected signs
are not required to be marked.
600.4 Markings.
(B) Signs with Lampholders for Incandescent
Lamps. Revised.
600.6 Disconnects. Each sign and outline
lighting system,
feeder circuit or branch circuit supplying a
sign, outline
lighting system, or skeleton tubing shall be
controlled by an externally operable switch
or circuit breaker that opens all ungrounded
conductors and controls no other load. The
600.6 Disconnects.
(A) Location.
(1) Within Sight of the Sign At Point of Entry to a
Sign Enclosure. The disconnect shall be required
for located at a point the feeder circuit or branch
circuit(s) or feeder passing through the supplying
a sign where enclosed in a Chapter 3 listed
raceway or outline lighting system enters a sign
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switch or circuit breaker shall open all
ungrounded conductors simultaneously on
multi-wire branch circuits in accordance with
210.4(B). Signs and outline lighting systems
located within fountains shall have the
disconnect located in accordance with
680.12.
Exception No. 1: A disconnecting means shall
not be required for an exit directional sign
located within a building.
Exception No. 2: A disconnecting means shall
not be required
for cord-connected signs with an attachment
plug.
(A) Location.
(1) Within Sight of the Sign At Point of Entry
to a Sign Enclosure. The disconnect shall be
located at a point the feeder circuit or
branch circuit(s) supplying a sign or outline
lighting system enters a sign enclosure or a
pole in accordance with 600.5(C)(3) and shall
disconnect all wiring where it enters the
enclosure of the sign or pole.
Exception: A disconnect shall not be required
for branch or feeder circuits passing through
the sign where enclosed in a Chapter 3 listed
raceway. disconnecting means shall be
within sight of the sign or outline lighting
system that it controls. Where the
disconnecting means is out of the line of
sight from any section that is able to be
enclosure or a pole in accordance with 600.5(C)(3)
and shall disconnect all wiring where it enters the
enclosure of the sign or pole.
Exception No.1: A disconnect shall not be
required for branch circuits or feeder circuits
conductor(s) passing through the sign where
enclosed in a Chapter 3 listed raceway or metal-
jacketed cable identified for the location.
Exception No. 2: A disconnect shall not be
required at the point of entry to sign enclosure or
sign body for branch circuit(s) or feeder
conductor(s) that supply an internal panelboard(s)
in a sign enclosure or sign body. Zthe conductors
shall be enclosed in a Chapter 3 listed raceway or
metal-jacketed cable identified for the location. A
field-applied permanent warning label that is
visible during servicing shall be applied to the
raceway at or near the point of entry into the sign
enclosure or sign body. The warning label shall
comply with 110.21(B) and state the following:
“Danger. This raceway contains energized
conductors.” The marking shall include the
location of the disconnecting means for the
energized conductor(s). The disconnecting means
shall be capable of being locked in the open
position in accordance with 110.25.
(2)Within Sight of the Sign. Add-
A permanent field-applied marking identifying the
location of the disconnecting means shall be
applied to the sign in a location visible during
servicing. The warning sign shall comply with
110.21(B).
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energized, the disconnecting means shall be
capable of being locked in the open position.
The provision for locking or adding a lock to
the disconnecting means must remain in
place at the switch or circuit breaker
whether the lock is installed or not. Portable
means for adding a lock to the switch or
circuit breaker shall not be permitted.
(3)Within Sight of the Controller. Add-
Exception: Where the disconnecting means is not
located within sight of the controller, a permanent
field-applied marking identifying the location of
the disconnecting means shall be applied to the
controller in a location visible during servicing. The
warning label shall comply with 110.21(B).
600.21 Ballasts, Transformers, and
Electronic Power Supplies, and Class 2
Power Sources. Ballasts, transformers,
electronic power supplies, and Class 2 power
sources shall be of the self-contained type or
be enclosed by placement in a listed sign
body or listed separate enclosure.
600.33 Class 2 Sign Illumination Systems
Secondary Wiring. Add-
(1) General Use. New section inserted.
(2) Other Building Locations. New section
inserted.
Table 600.33(A)(1) Application of Power Limited
Cable in Signs and Outline Lighting. New table.
Table 600.33(A)(2) Class 2 Cable Substitutions.
New table.
600.34 Photovoltaic (PV) Powered Signs. New
section and subsections.
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ARTICLE 604 Manufactured Wiring Systems
604.6 Listing Requirements. New section.
ARTICLE 605
Office Furnishings (Consisting or Lighting
Accessories and Wired Partitions)
605.2 General Definitions. Inserted.
Office Furnishings. New definition.
605.4 Partition Interconnections. The
electrical connection between partitions
office furnishings shall be a flexible assembly
identified for use with office furnishings
wired partitions or shall be permitted to be
installed using flexible cord, provided all the
following conditions are met:
(1) The cord is extra-hard usage type with 12
AWG or larger conductors, with an insulated
equipment grounding conductor.
(2) The partitions office furnishings are
mechanically contiguous.
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(3) The cord is not longer than necessary for
maximum
positioning of the partitions office
furnishings but is in no case to exceed 600
mm (2 ft).
(4) The cord is terminated at an attachment
plug-and-cord connector with strain relief.
605.5 Lighting Accessories. Lighting
equipment shall be listed and identified for
use with wired partitions office furnishings
and shall comply with 605.5(A), (B), and (C).
(A) Support. A means for secure attachment
or support shall be provided.
(B)Connection. Where cord-and-plug
connection is provided, it shall comply with
all of the following:
(1) The cord length shall be suitable for the
intended application but shall not exceed 2.7
m (9 ft) in length.
(2) The cord shall not be smaller than 18
AWG.
(3) The cord shall contain an equipment
grounding conductor.
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(4) Cords on the load side of a listed Class 2
power source shall not be required to
contain an equipment grounding conductor.
(5) The cord shall be of the hard usage type,
except as specified in 605.6(B)(6).
(6) A cord provided on a listed Class 2 power
source shall be of the type provided with the
listed luminaire assembly or of the type
specified in 725.130 and 725.125.
(7) Connection by other means shall be
identified as suitable for the condition of
use.
610.31 Runway Conductor Disconnecting
Means. A disconnecting means that has a
continuous ampere rating not less than that
calculated in 610.14(E) and (F) shall be
provided between the runway contact
conductors and the power supply. The
disconnecting means shall comply with
430.109. Such disconnecting means shall
consist of a motor circuit switch, circuit
breaker, or molded-case switch. This
disconnecting means shall be as follows:
(2) Lockable open in accordance with 110.25.
Capable of being locked in the open position.
The provision for locking or adding a lock to
the disconnecting means shall be installed on
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or at the switch or circuit breaker used as the
disconnecting means and shall remain in
place with or without the lock installed.
Portable means for adding a lock to the
switch or circuit breaker shall not be
permitted as the means required to be
installed at and remain with the equipment.
Exception: The runway conductor
disconnecting means for electrolytic cell lines
shall be permitted to be placed out of view
of the runway contact conductors where
either of the following conditions are met:
(1) Where a location in view of the
contact conductors is impracticable
or introduces additional or increased
hazards to persons or property.
(2) In industrial installations, with
written safety procedures, where
conditions of maintenance and
supervision ensure that only qualified
persons service the equipment.
610.32 Disconnecting Means for Cranes and
Monorail
Hoists. A disconnecting means in compliance
with 430.109 A motor-circuit switch,
molded-case switch, or circuit breaker shall
be provided in the leads from the runway
contact conductors or other power supply on
all cranes and monorail hoists. The
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disconnecting means shall be lockable open
in accordance with 110.25. capable of being
locked in the open position. The provision for
locking or adding a lock to the disconnecting
means shall be installed on or at the switch
or circuit breaker used as the disconnecting
means and shall remain in place with or
without the lock installed. Portable means
for adding a lock to the switch or circuit
breaker shall not be permitted.
Where a monorail hoist or hand-propelled
crane bridge
installation meets all of the following, the
disconnecting means shall be permitted to
be omitted:
(1) The unit is controlled from the ground or
floor level.
(2) The unit is within view of the power
supply disconnecting means.
(3) No fixed work platform has been
provided for servicing the unit.
Where the disconnecting means is not
readily accessible from the crane or monorail
hoist operating station, means shall be
provided at the operating station to open
the power circuit to all motors of the crane
or monorail hoist.
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ARTICLE 620 Elevators, Dumbwaiters,
Escalators, Moving Walks, Platform Lifts,
and Stairway Chairlifts
ARTICLE 620 Elevators, Dumbwaiters, Escalators,
Moving Walks, Platform Lifts, and Stairway
Chairlifts
620.11 Insulation of Conductors.
(A) Hoistway Door Interlock Wiring. The
conductors to the hoistway door interlocks from
the hoistway riser shall be one of the following:
(1) Flame retardant and suitable for a
temperature of not less than 200°C (392°F).
Conductors shall be Type SF or equivalent.
2) Physically protected using an approved
method, such that the conductor assembly is
flame retardant and suitable for a temperature of
not less than 2000C (3920F).
620.16 Short-Circuit Current Rating. New section
and subsections.
620.21 Wiring Methods. Add-
Exception: Cords and cables of listed cord-
and plug-connected equipment shall not be
required to be installed in a raceway.
620.23 Branch Circuits for Machine Room or
Control
Room/Machinery Space or Control Space
Lighting and
Receptacle(s).
(A) Separate Branch Circuit. The branch circuit(s)
supplying the lighting for machine rooms, control
rooms, machinery spaces, or control spaces shall
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be separate from the branch circuit(s) supplying
the receptacle(s) in those places. These circuits
shall supply no other loads. shall supply the
machine room or control room/machinery space
or control space lighting and receptacle(s).
Required lighting shall not be connected to the
load side of a ground-fault circuit interrupter.
620.41 Suspension of Traveling Cables.
Traveling cables shall be suspended at the
car and hoistways ends, or counterweight
end where applicable, so as to reduce the
strain on the individual copper conductors to
a minimum.
Traveling cables shall be supported by one of
the following means:
(1) By their steel supporting member(s)
(2) By looping the cables around supports for
unsupported lengths less than 30 m (100 ft)
(3) By suspending from the supports by a
means that automatically tightens around
the cable when tension is increased for
unsupported lengths up to 60 m (200 ft)
620.51 Disconnecting Means.
(D)(1) Identification and Signs More Than One
Driving Machine.
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(D)(2) Available Short-Circuit Current Field
Marking. New subsection.
(E) Surge Protection. New subsection.
620.62 Selective Coordination. Add-
Selective coordination shall be selected by a
licensed professional engineer or other
qualified person engaged primarily in the
design, installation, or maintenance of
electrical systems. The selection shall be
documented and made available to those
authorized to design, install, inspect,
maintain, and operate the system.
ARTICLE 625
625.2 Definitions.
Electric Vehicle Charging System
Cable Management System (Electric Vehicle
Supply Equipment). New definition.
Output Cable to the Electric Vehicle. New
definition.
Power-Supply Cord. New definition.
625.2 Definitions.
Charger Power Converter. New definition.
Fastened in Place. New definition.
Fixed in Place. New definition.
Portable (as applied to EVSE). New definition.
Primary Pad. New definition.
Wireless Power Transfer (WPT). New definition.
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Wireless Power Transfer Equipment (WPTE).
New definition.
625.9 625.10 Electric Vehicle Coupler.
625.17 Cords and Cables. New section.
625.18 Interlock. Add-
An interlock shall not be required for dc
supplies less than 50 volts dc.
625.22 Personnel Protection System. The shall
have a listed system of protection against electric
shock of personnel. Where cord-and-plug-
connected electric vehicle supply equipment is
used, the interrupting device of a listed personnel
protection system shall be provided and shall be
an integral part of the attachment plug or shall be
located in the power supply cable not more than
300 mm (12 in.) from the attachment plug. A
personnel protection system shall not be required
for supplies less than 60 volts dc.
625.41 Rating. Revised.
625.44 Electric Vehicle Supply Equipment
Connection. New section
625.44 Electric Vehicle Supply Equipment
Connection. Equipment shall be connected
Electric vehicle supply equipment shall be
permitted to be cord- and plug-connected to the
premises wiring system in accordance with one of
the following:
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(A) Connections to 125-Volt, Single-Phase, 15-
and 20-Ampere Receptacle Outlets Portable
Equipment. Portable Electric vehicle supply
equipment shall be connected to premises wiring
by one of the following methods: intended for
connection to
(1) A nonlocking, 2-pole, 3-wire grounding-type
receptacle outlets rated at 125 V, single phase,
15- and 20 amperes or from a supply of less than
50 volts dc.
(2) A nonlocking, 2-pole, 3-wire grounding -type
receptacle outlet rated at 60volt dc maximum, 15
or 20 amperes.
(B) Connections to Other Receptacle Outlets
Stationary Equipment. Stationary Electric vehicle
supply equipment intended to be fastened in
place in such a way as to permit ready removal for
interchange, facilitation of maintenance or repair,
or repositioning shall be connected to the
premises wiring system by one of the following
methods that is rated at 250 V maximum and
complying with all of the following:
(1) A nonlocking, 2-pole, 3-wire grounding-type
receptacle outlet rated 125-volt or 250 volt, single
phase, up to 50 ampere It is intended for
connection to nonlocking, 2-pole, 3-wire and 3-
pole, 4-wire, grounding type receptacle outlets
rated not more than 50 amperes.
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(2) A nonlocking, 3-pole, 4-wire grounding-type
receptacle outlet rated 250volt, three phase, up
to 50 ampere. EVSE is fastened in place to
facilitate any of the following:
(a) Ready removal for interchange.
(b) Facilitation of maintenance and repair.
(c) Repositioning of portable, movable, or EVSE
fastened in place.
(3) Any of the receptacle outlets in 625.44(A)(1)
or (2).
Power-supply cord The length of the power
supply cord, if provided, between the receptacle
outlet and the equipment shall be in accordance
with 625.17(A)(3). for electric vehicle supply
equipment fastened in place is limited to 1.8 m (6
ft).
(4) Receptacles are located to avoid physical
damage to the flexible cord.
All other electric vehicle supply equipment shall
be permanently wired and fastened in place to
the supporting surface, a wall, a pole, or other
structure. The electric vehicle supply equipment
shall have no exposed live part.
(C) Fixed Equipment. New section.
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625.25 625.46 Loss of Primary Source.
Means shall be provided such that, upon loss
of voltage from the utility or other electrical
system(s), energy cannot be back fed
through the electric vehicle and the supply
equipment to the premises wiring system
unless permitted by 625.26.
625.47 Multiple Feeder or Branch Circuits. New
section.
625.26 625.48 Interactive Systems. Electric
vehicle supply equipment and other parts of
a system, either on-board or off-board the
vehicle, that are intended identified for and
intended to be interconnected to a vehicle
and also serve as an optional standby system
or an electric power production source or
provide for bi-directional power feed shall be
listed and marked as suitable for that
purpose. When used as an optional standby
system, the requirements of Article 702 shall
apply, and when used as an electric power
production source, the requirements of
Article 705 shall apply.
(4) Supply Circuits. The supply circuit to the
mechanical ventilation equipment shall be
electrically interlocked with the electric
vehicle supply equipment and shall remain
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energized during the entire electric vehicle
charging cycle. Electric vehicle supply
equipment shall be marked in accordance
with 625.15. Electric vehicle supply
equipment receptacles rated at 125 volts,
single phase, 15 and 20 amperes shall be
marked in accordance with 625.15(C) and
shall be switched, and the mechanical
ventilation system shall be electrically
interlocked through the switch supply power
to the receptacle. Electric vehicle supply
equipment supplied from less than 50 volts
dc shall be marked in accordance with
625.15(C) and shall be switched, and the
mechanical ventilation system shall be
electrically interlocked through the switch
supply power to the electric vehicle supply
equipment.
625.50 Location. Add-
This requirement does not apply to portable
electric vehicle supply equipment constructed in
accordance with 625.44(A).
ARTICLE 626 Electrified Truck Parking Spaces
626.31 Disconnecting Means and Receptacles.
(C) Rating(s).
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(3) A 20-ampere, 1000-volt, 3-phase, 3-pole, 4-
wire receptacle, pin and sleeve.
626.32 Separable Power Supply Cable Assembly.
(A) Rating(s). Add- one of the following:
(3) A 20-ampere, 1000-volt, 3-phase.
(C) Attachment Plug(s) and Cord Connector(s).
Add- one of the following:
(3) 20-ampere, 1000-volt, 3-phase, 3-pole, 4-wire
and intended for use with a 20-ampere, 1000-
volt, 3-phase, 3-pole, 4-wire receptacles and
inlets, respectively.
ARTICLE 640 Audio Signal Processing,
Amplification, and Reproduction Equipment
ARTICLE 640 Audio Signal Processing,
Amplification, and Reproduction Equipment
640.1 Scope.
(A) Covered. This article covers equipment
and wiring for audio signal generation,
recording, processing, amplification and
reproduction; distribution of sound; public
address; speech input systems; temporary
audio system installations; and electronic
organs or other electronic musical
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instruments. This also includes audio
systems subject to Article 517, Part VI, and
Articles 518, 520, 525, and 530.
(B)Not Covered. This article does not cover
the installation and wiring of fire and
burglary alarm signaling devices.
640.3 Locations and Other Articles.
(B) Ducts, Plenums, and Other Air-Handling
Spaces.
Add- Exception No. 1: Class 2 and Class 3 cables
installed in accordance with 725.135(B) and Table
725.154 shall be permitted to be installed in ducts
specifically fabricated for environmental air.
Exception No. 2: Class 2 and Class 3 cables
installed in accordance with 725.135(C) and Table
725.154 shall be permitted to be installed in other
spaces used for environmental air (plenums).
ARTICLE 645 Information Technology
Equipment
ARTICLE 645 Information Technology Equipment
645.3 Other Articles.
(B) Plenums Wiring and cabling in Other Spaces
Used for Environmental Air (Plenums). Revised.
(E) Fire Alarm Cables and Equipment. Add-
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Only fire alarm cables listed in accordance with
Part IV of Article 760 and listed fire alarm
equipment shall be permitted to be installed in an
information technology equipment room.
(F) Cable Routing Assemblies, Communications
Wires, Cables, Raceways, and Equipment. Parts I,
II, III, IV, and
V of Article 800 shall apply to cable routing
assemblies, communications wires, cables,
raceways, and equipment installed in an
information technology equipment room. Only
communication wires and cables listed in
accordance with 800.179, cable routing
assemblies, and communications equipment
listed in accordance with 800.170 shall be
permitted to be installed in an information
technology equipment room. Article 645 shall
apply to the powering of communications
equipment in an information technology
equipment room.
(F) Community Antenna Television and Radio
Distribution Systems Cables and
Equipment. Parts I, II, III, IV, and V of
Article 820 shall apply to community
antenna television and radio distribution
systems cables and equipment installed in
an information technology equipment
room. Only communication antenna
television and radio distribution cables
listed in accordance with 820.179 and
listed CATV equipment shall be permitted
to be installed in an information
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technology equipment room. Article 645
shall apply to the powering of community
antenna television and radio distribution
systems equipment installed in an
information technology equipment room.
(H)Optical Fiber Cables. New subsection.
645.4 Special Requirements for Information
Technology
Equipment Room. This article shall be
permitted to provide alternate wiring
methods to the provisions of Chapters 1
through 4 Chapter 3 and Article 708 for
power wiring, Parts I and III of Article 725
725.154 for signaling wiring, and Parts I and
V of Article 770 770.113© and Table
770.154(a) for optical fiber cabling when
where all of the following conditions are
met:
A separate heating/ventilating/air-
conditioning (HVAC) system is provided in
one of the methods identified in 645.492) a
or b.
a. That is dedicated for information
technology equipment use and is
separated from other areas of
occupancy, or
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b. An HVAC system that serves other
occupancies and meets all of the
following:
i. Also serves the information
technology equipment room.
ii. Provides fire/smoke dampers
at the point of penetration of
the room boundary.
iii. Activates the damper
operation upon initiation by
smoke detector alarms, by
operation of the
disconnecting means required
by 645.10, or by both. Any
HVAC system that serves
other occupancies shall be
permitted to also serve the
information technology
equipment room if fire/smoke
dampers are provided at the
point of penetration of the
room boundary. Such
dampers shall operate on
activation of smoke detectors
and by operation of the
disconnecting means required
by 645.10.
645.5 Supply Circuits and Interconnecting Cables.
(E) Under Raised Floors. Revised.
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Table 645.10(B)(5) Cables Installed Under Raised
Floors. New table.
645.14 System Grounding. New section.
645.18 Surge Protection for Critical Operations
Data Systems. New section.
645.27 Selective Coordination. New section.
ARTICLE 646 Module Data Centers. New
article.
ARTICLE 646 Module Data Centers. New article.
646.3 Other Articles.
(B) Plenums Wiring and Cabling in Other Spaces
Used for Environmental Air (Plenums). Revised.
(E) Fire Alarm Equipment. The provisions of Parts
I, II, and III of Article 760 shall apply to fire alarm
systems, cables, and equipment installed in an
MDC, when provided. Only fire alarm cables listed
in accordance with Part IV of Article 760 and
listed fire alarm equipment shall be permitted to
be installed in an MDC.
(F) Cable Routing Assemblies and
Communications Wires, cables, Raceways, and
Equipment. Parts I, II, III, IV, and V of Article 800
shall apply to cable routing systems
communications wires, cables, raceways, and
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equipment installed in an MDC. Only
communications wires and cables listed in
accordance with Part IV of Article 760 and listed
fire alarm equipment shall be permitted to be
installed in an MDC.
(G) Community Antenna Television and Radio
Distribution Systems Cables and Equipment.
Parts I, II, III, IV, and V of Article 820 shall apply to
community antenna television and radio
distribution systems equipment installed in an
MDC. Only community antenna television and
radio distribution cables listed in accordance with
820.179 and listed CATV equipment shall be
permitted to be installed in an MDC.
646.7 Short-Circuit Current Rating.
(B) MDCs Connected to Branch Circuits and
Feeders. Add-
Exception: This requirement shall not apply to
listed and labeled equipment connected to branch
circuits located inside of the MDC equipment
enclosure.
ARTICLE 647 Sensitive Electronic Equipment
647.6 Grounding.
(A) General. The transformer secondary
center tap of the 60/120-volt, 3-wire system
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shall be grounded as provided in 250.30 as a
separately derived single-phase, 3-wire
system.
ARTICLE 650 Pipe Organs
650.2 Definitions. New Section.
650.5 Grounding or Double Insulation of the DC
Power Supply. The installation of dc power supply
shall comply with either of the following:
(1) The dc power supply shall be double insulated.
(2) The metallic case of the dc power supply shall
be bonded to the input equipment grounding
conductor.
rectifier shall be bonded to the equipment
grounding conductor according to the provisions
in Article 250, Parts V, VI, VII, and VIII.
650.7 Installation of Conductors. Cables shall be
securely
fastened in place and shall be permitted to be
attached directly to the organ structure without
insulating supports. Cables Splices shall not be
required to be enclosed in boxes or other
enclosures. Control equipment and busbars
connecting common-return conductors shall be
permitted to be attached directly to the organ
structure without insulation supports. placed in
contact with other conductors. Abandoned cables
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that are not terminated at equipment shall be
identified with a tag of sufficient durability to
withstand the environment involved.
650.9 Protection from Accidental Contact. New
section.
ARTICLE 660 X-Ray Equipment
660.5 Disconnecting Means. Add-
Exception: The disconnecting means for the X-ray
equipment shall not be required under either of
the following conditions, provided that the
controller disconnecting means is lockable in
accordance with 110.25:
(1) Where such a location of the disconnection
means for the X-ray equipment is
impracticable or introduces additional or
increased hazards to persons or property.
(2) In industrial installations, with written
safety procedures, where conditions of
maintenance and supervision ensure that
only qualified persons service the
equipment.
ARTICLE 670 Industrial Machinery
670.5 Short-Circuit Current Rating.
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(1) Industrial machinery shall not be installed
where the available fault short-circuit current
exceeds its short-circuit current rating as marked
in accordance with 670.3(A)(4).
(2) Industrial machinery shall be legibly marked in
the field with the maximum available short-circuit
current. The field marking(s) shall include the date
the short-circuit current calculation was
performed and be of sufficient durability to
withstand the environment involved.
670.7 Surge Protection. New section.
ARTICLE 680 Swimming Pool, Fountains, and
Similar Installations
ARTICLE 680 Swimming Pool, Fountains, and
Similar Installations
680.2 Definitions.
Electrically Powered Pool Lift. New definition.
608.7 Grounding and Bonding Terminals. New
section.
680.10 680.11 Underground Wiring Location.
Underground wiring shall be permitted not be
permitted under the pool or within the area
extending 1.5 m (5 ft) horizontally from the inside
wall of the pool unless this wiring is necessary to
supply pool equipment permitted by this article.
Where space limitations prevent wiring from
being routed a distance 1.5 m (5 ft) or more from
the pool, such wiring shall be permitted where
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installed in complete raceway systems of rigid
metal conduit, intermediate metal conduit, rigid
polyvinyl chloride conduit, reinforced
thermosetting resin conduit, or Type MC cable, or
a nonmetallic raceway system. All metal conduit
shall be corrosion resistant and suitable for the
location. Underground wiring shall not be
permitted under the pool unless this wiring is
necessary to supply pool equipment permitted by
this article. The Minimum cover depth shall be as
given in Table 680.10 300.5.
680.11 680.12 Equipment Rooms and Pits.
Revised.
680.14 Corrosive Environment. New section and
subsections.
680.22 Lighting, Receptacles, and
Equipment.
(B) Luminaires, Lighting Outlets, and Ceiling-
Suspended (Paddle) Fans.
(6) Low-Voltage Luminaires. New section.
680.22 Lighting, Receptacles, and Equipment.
(B)(7) Low-voltage Gas-Fired Luminaires,
Decorative Fireplaces, Fire Pits, and Similar
Equipment. Insert new subsection.
680.26 Equipotential Bonding.
(C) Pool Water. Revised.
680.27 Specialized Pool Equipment.
(B)(1) Motors and Controllers. Add-
Exception: Motors that are part of listed systems
with ratings not exceeding the low-voltage
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contact limit that are supplied by listed
transformers or power supplies that comply with
680.23(A)(2) shall be permitted to be located less
than 1.5 m (5 ft) from the inside walls of the pools.
(B)(2) Protection. Add-
Exception: Motors that are part of listed systems
with ratings not exceeding the low-voltage
contact limit that are supplied by listed
transformers or power supplies that comply with
680.23(A)(2).
680.28 Gas-Fired Water Heater. New section.
III. Storable Pools, Storable Spas, and
Storable Hot Tubs. Revised- add “Storable
Spas and Storable Hot Tubs” to all references
to Storable Pools.
680.42 Outdoor Installations.
A. Flexible Connections.
(1) Flexible Conduit. Liquidtight flexible
metal conduit or
liquidtight flexible nonmetallic conduit shall
be permitted in lengths of not more than 1.8
m (6 ft) external to the spa or hot tub
enclosure in addition to the length needed
within the enclosure to make the electrical
connection.
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(2) Cord-and-Plug Connections.
(B) Bonding. Bonding by metal-to-metal
mounting on a common frame or base shall
be permitted. The metal bands or hoops
used to secure wooden staves shall not be
required to be bonded as required in 680.26.
Equipotential bonding of perimeter surfaces
in accordance with 680.26(B)(2) shall not be
required to be provided for spas and hot
tubs where all of the following conditions
apply:
(1) The spa or hot tub shall be listed as a
self-contained spa for aboveground
use.
(2) The spa or hot tub shall not be
identified as suitable only for indoor
use.
(3) The installation shall be in
accordance with the manufacturer’s
instructions and shall be located on
or above grade.
(4) The top rim of the spa or hot tub shall
be at least 710 mm (28 in.) above all
perimeter surfaces that are within
760 mm (30 in.) measured
horizontally from the spa or hot tub.
The height of nonconductive external
steps for entry to or exit from the
self-contained spa shall not be used
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to reduce or increase this rim height
measurement.
680.43 Indoor Installation. Add-
Exception No. 3: For a dwelling unit(s) only,
where a listed spa or hot tub is installed
indoors, the wiring method requirements of
680.42(C) shall also apply.
680.74 Bonding. Revised-
(A) General. The following parts shall be bonded
together:
(1) All metal fittings within or attached to the tub
structure that are in contact with the circulating
water.
(2) Metal parts of electrical equipment associated
with the tub water circulating system, including
pump and blower motors.
(3) Metal-sheathed cables and raceways and
metal piping that are within 1.5 m (5 ft) of the
inside walls of the tub and not separated from the
tub by a permanent barrier.
(4) All exposed metal surfaces that are within 1.5
m (5 ft) of the inside walls of the tub and not
separated from the tub area by a permanent
barrier.
(5) Electrical devices and controls that are not
associated with the hydromassage tubs and that
are located within 1.5 m (5 ft) from such units.
Exception No. 1: Small conductor surfaces not
likely to become energized, such as air and water
jets, supply valve assemblies, and drain fittings
not connected to metallic piping, and towel bars,
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mirror frames, and similar nonelectrical
equipment not connected to metal framing shall
bot be required to be bonded.
Exception No. 2: Double-insulated motors and
blowers shall not be bonded.
(B)Metal parts required to be bonded by this
section shall be Both metal piping systems and
grounded metal parts in contact with the
circulating water shall be bonded together using a
solid copper bonding jumper, insulated, covered,
or bare, not smaller than 8 AWG. The bonding
jumper(s) shall be connected to the terminal on
the circulating pump motor that is intended for
this purpose. The bonding jumper shall not be
required to be connected to a double insulated
circulating pump motor. The 8 AWG or larger solid
copper bonding jumper shall be required for
equipotential bonding in the area of the
hydromassage bathtub and shall not be required
to be extended or attached to any remote
panelboard, service equipment, or any electrode.
In all installations a The 8 AWG or larger solid
copper bonding jumper shall be long enough to
terminate on a replacement non-double-insulated
pump or blower motor shall be provided
and shall be terminated to the equipment
grounding conductor of the branch circuit of the
motor when a double-insulated circulating pump
or blower motor is used.
Part VIII. Electrically Powered Pool Lifts. New
part, sections and subsections.
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ARTICLE 690 Solar Photovoltaic (PV)
Systems
ARTICLE 690 Solar Photovoltaic (PV) Systems
690.2 Definitions.
DC-to-DC Converter: New definition.
Direct-Current (dc) Combiner. New
definition.
Multimode Inverter. New definition.
690.2 Definitions.
DC-to-DC Converter Output Circuit: New
definition.
DC-to-DC Converter Source Circuit: New
definition.
Generating Capacity: New definition.
Interactive Inverter Output Circuit: New
definition.
Photovoltaic System DC Circuit: New definition.
690.4 Installation General Requirements.
(D) (B) Equipment. Inverters, motor
generators, photovoltaic PV modules,
photovoltaic PV panels, ac photovoltaic PV
modules, dc combiners, dc-to-dc converters,
source-circuit combiners, and charge
controllers intended for use in photovoltaic
690.4 General Requirements.
(D) Multiple Inverters PV Systems.
(E) Locations Not Permitted. New section.
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PV power systems shall be identified and
listed for the PV application.
(C) Qualified Personnel. New section.
H) (D) Multiple Inverters. A PV system shall
be permitted to have multiple utility-
interactive inverters installed in or on a
single building or structure. Where the
inverters are remotely located from each
other, a directory in accordance with 705.10
shall be installed at each dc PV system
disconnecting means, at each ac
disconnecting means, and at the main
service disconnecting means showing the
location of all ac and dc PV system
disconnecting means in the building.
Exception: A directory shall not be required
where all inverters and PV dc disconnecting
means are grouped atthe main service
disconnecting means.
690.5 Ground-Fault Protection. Grounded dc
photovoltaic PV arrays shall be provided with
dc ground-fault protection meeting the
requirements of 690.5(A) through (C) to
reduce fire hazards. Ungrounded dc
photovoltaic PV arrays shall comply with
690.35.
Exception No. 1: Ground-mounted or pole-
mounted photovoltaic arrays with not more
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than two paralleled source circuits and with
all dc source and dc output circuits isolated
from buildings shall be permitted without
groundfault protection.
Exception No. 2: Photovoltaic arrays installed
at other than dwelling units shall be
permitted without ground-fault protection if
each equipment grounding conductor is sized
in accordance with 690.45.
(A) Ground-Fault Detection and
Interruption. The ground-fault protection
device or system shall:
(1) Be capable of detecting a ground
fault in the PV array dc current-
carrying conductors and components,
including any intentionally grounded
conductors.
(2) Interrupt the flow of fault current.
(3) Provide an indication of the fault, and
(4) Be listed for providing PV ground-
fault protection.
be capable of detecting a ground-fault
current, interrupting the flow of fault
current, and providing an indication of the
fault.
Automatically opening the grounded
conductor for measurement purposes or of
the faulted circuit to interrupt the ground-
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fault current path shall be permitted. If a
grounded conductor is opened to interrupt
the ground-fault current path, all conductors
of the faulted circuit shall be automatically
and simultaneously opened.
Manual operation of the main PV dc
disconnect shall not activate the ground-
fault protection device or result in grounded
conductors becoming ungrounded.
(C) Labels and Markings. A warning label
shall appear on the utility-interactive
inverter or be applied by the installer near
the ground-fault indicator at a visible
location, stating the following:
WARNING
ELECTRIC SHOCK HAZARD
IF A GROUND FAULT IS INDICATED,
NORMALLY GROUNDED CONDUCTORS
MAY BE UNGROUNDED AND ENERGIZED
When the photovoltaic PV system also has
batteries, the same warning shall also be
applied by the installer in a visible location at
the batteries. The warning sign(s) or label(s)
shall comply with 110.2(B).
690.7 Maximum Voltage. The maximum voltage
of PV system dc circuits shall be the highest
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voltage between any two circuit conductors or
any conductor and ground. PV System dc circuits
on or in one- and two-family dwellings shall be
permitted to have a maximum voltage of 600
volts or less. PV system dc circuits on or in other
types of buildings shall be permitted to have
maximum voltage of 1000 volts or less. Where not
located on or in buildings, listed dc PV equipment,
rated at maximum voltage of 1500 volts or less,
shall not be required to comply with Parts II and
III of Article 490.
(A) Maximum Photovoltaic Source and Output
Circuits System Voltage. In a dc photovoltaic
source circuit or output circuit, the maximum
photovoltaic system voltage for that circuit shall
be calculated in accordance with one of the
following methods:
(1) Instructions in listing or labeling of the
module: as the sum of the PV module rated open-
circuit voltage of the series-connected
photovoltaic modules corrected for the lowest
expected ambient temperature using the open-
circuit voltage temperature coefficients in
accordance with the instructions included in the
listing or labeling of the module.
(2) Crystalline and mutlicrystalline modules: For
crystalline and multicrystalline silicon modules,
the rated open-circuit voltage shall be multiplied
by the correction factor provided in Table 690.7.
(3) PV systems of 100 kW or larger: For PV
systems with a generating capacity of 100 kW or
greater, a documented and stamped PV design,
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using an industry standard method and provided
by a licensed professional electrical engineer,
shall be permitted.
The maximum voltage shall be used to determine
the voltage, rating of conductors, cables,
disconnects, overcurrent devices, and other
equipment.
This voltage shall be used to determine the
voltage rating of cables, disconnects, overcurrent
devices, and other equipment. Where the lowest
expected ambient temperature is below −40°C
(−40°F), or where other than crystalline or
multicrystalline silicon photovoltaic modules are
used, the system voltage adjustment shall be
made in accordance with the manufacturer’s
instructions. When open-circuit voltage
temperature coefficients are supplied in the
instructions for listed PV modules, they shall be
used to calculate the maximum photovoltaic
system voltage as required by 110.3(B) instead of
using
(B) Direct-Current Utilization Circuits DC-to-DC
Source and Output Circuits. In a dc-to-dc
converter source and output circuit, the
maximum voltage shall be calculated in
accordance with 690.7(B)(1) or (B)(2)The voltage
of dc
utilization circuits shall conform to 210.6.
(1) Single DC-to-DC Converter. For circuits
connected to the output of a single dc-to-
dc converter, the maximum voltage shall
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be the maximum rated voltage output of
the dc-to-dc converter.
(2) Two or more Series Connected DC-To-DC
Converters. For circuits connecting the
output of two or more series-connected
dc-to-dc converters, the maximum voltage
shall be determined in accordance with
the instructions included in the listing or
labeling of the dc-to-dc converter. If these
instructions do not state the rated voltage
of the series-connected dc-to-dc
converters, the maximum voltage shall be
the sum of the maximum rated voltage
output of the dc-to-dc converters in series.
(C) Photovoltaic Source and Output Circuits. In
one and
two-family dwellings, photovoltaic source circuits
and
photovoltaic output circuits that do not include
lampholders, fixtures, or receptacles shall be
permitted to have a maximum photovoltaic
system voltage up to 600 volts. Other installations
with a maximum photovoltaic system voltage
over 600 volts shall comply with Article 690, Part
IX.
(D) Circuits over 150 Volts to Ground. In one- and
two family dwellings, live parts in photovoltaic
source circuits and photovoltaic output circuits
over 150 volts to ground shall not be accessible to
other than qualified persons while energized.
(E) (C) Bipolar Source and Output Circuits. For 2-
wire dc circuits connected to bipolar PV arrays,
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systems, the maximum system voltage shall be
the highest voltage between the 2-wire circuit
conductors where one conductor of the 2-wire
circuit is connected to the functional ground
reference (center tap). To prevent overvoltage in
the event of a ground-fault or arc-fault, the array
shall be isolated from the ground reference and
isolated into two 2-wire circuits. if all of the
following conditions apply:
(1) One conductor of each circuit of a bipolar
subarray is
solidly grounded.
Exception: The operation of ground-fault or arc-
fault devices (abnormal operation) shall be
permitted to interrupt this connection to ground
when the entire bipolar array becomes two
distinct arrays isolated from each other and the
utilization equipment.
(2) Each circuit is connected to a separate
subarray.
(3) The equipment is clearly marked with a label
as follows:
WARNING
BIPOLAR PHOTOVOLTAIC ARRAY.
DISCONNECTION OF NEUTRAL
OR GROUNDED CONDUCTORS
MAY RESULT IN OVERVOLTAGE
ON ARRAY OR INVERTER.
609.8 Circuit Size and Current.
(A) Calculation of Maximum Circuit Current.
609.8 Circuit Sizing and Current.
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(5) DC-to-DC Converter Output Current.
New section.
(B) Ampacity and Overcurrent Device
Ratings Conductor Ampacity. Photovoltaic
PV system currents shall be considered to be
continuous. Circuit conductors shall be sized
to carry not less than the larger of
690.8(B)(1) or (2).
(1) One hundred and twenty-five percent of
the maximu currents calculated in 690.8(A)
before the application of adjustment and
correction factors. Overcurrent Devices.
Overcurrent devices, where required, shall
be rated as required by 690.8(B)(1)(a)
through (1)(d).
(a) To carry not less than 125 percent of the
maximum
currents calculated in 690.8(A).
Exception: Circuits containing an assembly,
together with its overcurrent device(s), that
is listed for continuous operation at 100
percent of its rating shall be permitted to be
used at 100 percent of its rating.
(b) Terminal temperature limits shall be in
accordance with 110.3(B) and 110.14(C).
(A)(6) DC-to-DC Converter Output Circuit
Current. New subsection.
(B)(3) Adjustable Electronic Overcurrent
Protective Device. New subsection.
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(c) Where operated at temperatures greater
than 40°C (104°F), the manufacturer’s
temperature correction factors shall apply.
(d) The rating or setting of overcurrent
devices shall be permitted in accordance
with 240.4(B), (C), and (D).
(2) Conductor Ampacity. Circuit conductors
shall be sized o carry not less than the larger
of 690.8(B)(2)(a) or (2)(b).
(a) One hundred and twenty-five percent of
the maximum currents calculated in 690.8(A)
without any additional correction factors for
conditions of use.
(b) The maximum currents calculated in
690.8(A) after conditions of use have been
applied.
(c) The conductor selected, after the
application of adjustment and correction
factors conditions of use, shall be protected
by the overcurrent protective device, where
required.
690.9 Overcurrent Protection.
(A) Circuits and Equipment. Photovoltaic PV
source circuit, photovoltaic PV output circuit,
inverter output circuit, and storage battery
circuit conductors and equipment shall be
690.9 Overcurrent Protection.
(B) Overcurrent Device Rating. Overcurrent
device(s) used in PV system dc circuits shall be
listed for use in PV systems. Overcurrent devices,
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protected in accordance with the
requirements of Article 240. Protection
devices for PV source circuits and PV output
circuits shall be in accordance with the
requirements of 690.9(B) through (E).
Circuits, either ac or dc, connected to
current-limited supplies (e.g., PV modules, ac
output of utility-interactive inverters), and
also connecter to sources having significantly
higher current availability (e.g., parallel
strings of modules, utility power), shall be
protected at the source from overcurrent.re
than one electrical source shall have
overcurrent devices located so as to provide
overcurrent protection from all sources.
Exception: An overcurrent device shall not be
required for
PV modules or PV source circuit conductors
sized in accordance with 690.8(B) where one
of the following applies:
(a) There are no external sources such as
parallel connected source circuits, batteries,
or backfeed from inverters.
(b) The short-circuit currents from all sources
do not exceed the ampacity of the
conductors or the maximum overcurrent
protective device size specified on the PV
module nameplate.
where required, shall be rated in accordance with
one of the following:
(1) ratings shall be Not less than 125 percent of
the maximum current calculated in 690.8(A).
(2) Exception: Circuits containing An assembly,
together with its overcurrent device(s), that is
listed for continuous operation at 100 percent of
its rating shall be permitted to be used at 100
percent of its rating.
(3) Adjustable electronic overcurrent protective
devices rated or set in accordance with 240.6.
(D) (C) Photovoltaic Source and Output Circuits.
A single overcurrent protective device, where
required, shall be permitted to protect the PV
modules and conductors of each source circuit or
the conductors of each output circuit. Where
single overcurrent protection devices are used to
protect PV source or output circuits, all
overcurrent devices shall be places in the same
polarity for all circuits within a PV system. PV
overcurrent devices shall be required to provide
overcurrent protection in PV source and output
circuits. The overcurrent devices shall be
accessible but shall not be required to be readily
accessible.
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(B)Overcurrent Device Ratings. New section
inserted.
Power Transformers. Overcurrent
protection for a
transformer with a source(s) on each side
shall be provided in accordance with 450.3
by considering first one side of the
transformer, then the other side of the
transformer, as the primary.
Exception: A power transformer with a
current rating on the side connected toward
the utility-interactive inverter output, not less
than the rated continuous output current of
the inverter, shall be permitted without
overcurrent protection from the inverter.
(D) (C) Direct-Current Rating. Overcurrent
devices, either fuses or circuit breakers, used
in any dc portion of a photovoltaic PV power
system shall be listed for use in dc circuits
and shall have the appropriate voltage,
current, and interrupt ratings.
(D) (D) Photovoltaic Source and Output
Circuits. Revised.
(E) Series Overcurrent Protection. In
grounded PV source circuits, a single
overcurrent protection device, where
required, shall be permitted to
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protect the PV modules and the
interconnecting conductors. In
ungrounded PV source circuits
complying with 690.35, an
overcurrent protection device, where
required, shall be installed in each
ungrounded circuit conductor and
shall be permitted to protect the PV
modules and the interconnecting
cables.
690.10 Stand-Alone Systems. Revised.
690.12 Rapid Shutdown of PV Systems on
Buildings. New section.
690.12 Rapid Shutdown of PV Systems on
Buildings.
Add- Exception: Ground mounted PV system
circuits that enter buildings, of which the sole
purpose is to house PV system equipment, shall
not be required to comply with 690.12.
(A) Controlled Conductors. New section.
(B) Controlled Limits. New section.
(C) Initiation Device. New section.
(D) Equipment. New section.
690.13 All Conductors Building or Other
Structures Supplied by a Photovoltaic
System. Revised.
690.13 Building or Other Structures Supplied by a
Photovoltaic System Disconnecting Means.
Revised.
690.15 Disconnection of Photovoltaic
Equipment. Means shall be provided to
disconnect equipment, such as inverters,
690.15 Disconnection of Photovoltaic
Equipment. Isolating devices Means shall be
provided to isolate PV modules, ac PV modules,
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batteries, and charge controllers, and the
like, from all ungrounded conductors of all
sources. If the equipment is energized from
more than one source, the disconnecting
means shall be grouped and identified.
A single disconnecting means in accordance
with 690.17 shall be permitted for the
combined ac output of one or more inverters
or ac modules in an interactive system.
(A) Utility-Interactive Inverters Mounted
in Not Readily Accessible Locations.
Utility-interactive inverters shall be
permitted to be mounted on roofs or
other exterior areas that are not
readily accessible and shall comply
with 690.15(A)(1) through (4):
(1) A dc PV disconnecting means shall
be mounted within sight of or in
each inverter.
(2) An ac disconnect means shall be
mounted within sight of or in
each inverter.
(3) The ac output conductors from
the inverter and an additional ac
disconnecting means for the
inverter shall comply with
690.13(A).
(4) A plague shall be installed in
accordance with 705.10.
(B) Equipment. Equipment such as PV
source circuit isolating switches,
fuses, dc-to-dc converters inverters, and
disconnect equipment, such as inverters,
batteries, and charge controllers, from all
ungrounded conductors that are not solidly
grounded. An equipment disconnecting means or
a PV system disconnecting means shall be
permitted in place of an isolating device. Where
the maximum circuit current is greater than 30
amperes for the output circuit of a dc combiner or
the input circuit of a charge controller or inverter,
an equipment disconnecting means shall be
provided for isolation. Where a charge controller
or inverter has multiple input circuits, a single
equipment disconnecting means shall be
permitted to isolate the equipment from the
input circuits of all sources. If the equipment is
energized from more than one source, the
disconnecting means shall be grouped and
identified. A single disconnecting means in
accordance with 690.17 shall be permitted for the
combined ac output of one or more inverters or
ac modules in an interactive system.
(A) Utility-Interactive Inverters Mounted in
Not Readily Accessible Locations. Isolating
devices or equipment disconnecting
means shall be installed in circuits
connected to equipment at a location
within the equipment, or within sight and
within 3 m (10 ft) of the equipment, An
equipment disconnecting means shall be
permitted to be remote from the
equipment where the equipment
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overcurrent devices, dc-to-dc
converters, and blocking diodes shall
be permitted on the PV side of the PV
disconnecting means.
(C) Direct-Current Combiner
Disconnects. The dc output of dc
combiners mounted on roofs of
dwellings or other buildings shall
have a load break disconnecting
means located in the combiner or
within 1.8 m (6 ft) of the combiner.
The disconnecting means shall be
permitted to be remotely controlled
but shall be manually operable locally
when control power is not available.
disconnecting means can be remotely
operated from within 3 m (10 ft) of the
equipment. Utility-interactive inverters
shall be permitted to be mounted on roofs
or other exterior areas that are not readily
accessible and shall comply with
690.15(A)(1) through (4):
(1) A dc PV disconnecting means shall be
mounted within sight of or in each
inverter.
(2) An ac disconnect means shall be
mounted within sight of or in each
inverter.
(3) The ac output conductors from the
inverter and an additional ac
disconnecting means for the inverter
shall comply with 690.13(A).
(4) A plague shall be installed in
accordance with 705.10.
(B) Equipment Interrupting Rating. New
section. Equipment such as PV source
circuit isolating switches, overcurrent
devices, dc-to-dc converters, and blocking
diodes shall be permitted on the PV side of
the PV disconnecting means.
(C) Direct-Current Combiner Disconnects
Isolating Device. New section. The dc
output of dc combiners mounted on roofs
of dwellings or other buildings shall have a
load break disconnecting means located in
the combiner or within 1.8 m (6 ft) of the
combiner. The disconnecting means shall
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be permitted to be remotely controlled
but shall be manually operable locally
when control power is not available.
(D) Equipment Disconnecting Means. New
section.
690.17 Switch or Circuit Breaker Disconnect
Type. Revised.
690.31 Methods Permitted.
(B) Identification and Grouping. New
section.
(B) (C) Single-Conductor Cable.
(1) General. Single-conductor cable type
USE-2, and single-conductor cable listed and
labeled as photovoltaic (PV) wire shall be
permitted in exposed outdoor locations in
photovoltaic PV source circuits for
photovoltaic PV module interconnections
within the photovoltaic PV array.
Exception: Raceways shall be used when
required by
690.31(A).
(2) Cable Tray. New section.
(D) Multiconductor Cable. New section.
690.31 Methods Permitted.
(A) Wiring Systems. Add-
For ambient temperatures exceeding 300C (860F),
conductor ampacities shall be corrected in
accordance with Table 690.31(A).
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(G) Direct-Current Photovoltaic Source and
Direct-Current Output Circuits Inside on or a
Building.
(1) Embedded in Building Surfaces. New
section.
(4) Marking and Labeling Methods and
Locations. The labels or markings shall be
visible after installation. The labels shall be
reflective, and all letters shall be capitalized
and shall be a minimum height of 9.5 mm
(3/8 in) in white in a red background.
Photovoltaic PV power circuit labels shall
appear on every section of the wiring system
that is separated by enclosures, walls,
partitions, ceilings, or floors. Spacing
between labels or markings, or between a
label and a marking, shall not be more than 3
m (10 ft). Labels required by this section shall
be suitable for the environment where they
are installed.
(I)Bipolar Photovoltaic Systems. New
section.
(J) Module Connection Arrangement. New
section.
Table 690.31(A) Correction Factors. New table.
Table 690.31(E) Minimum PV Wire Strands. New
table.
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690.35 Ungrounded Photovoltaic Power
Systems.
(C) Ground-Fault Protection. All photovoltaic
PV source and output circuits shall be
provided with a ground-fault protection
device or system that complies with (1)
through (4):
(1) Detects a ground fault(s) in the PV array
dc current-carrying conductors and
components.
(2) Indicates that a ground fault has occurred
(3) Automatically disconnects all conductors
or causes the inverter or charge controller
connected to the faulted circuit to
automatically cease supplying power to
output circuits.
(4) Is listed for providing PV ground-fault
protection.
(D) Conductors. The photovoltaic PV source
conductors shall consist of the following:
(1) Metallic or nonmetallic jacketed
multiconductor cables
(2) Conductors installed in raceways, or
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(3) Conductors listed and identified as
Photovoltaic (PV) wire installed as exposed,
single conductors.
(4)Conductors that are direct-buried and
identified for direct-burial use.
690.41 System Grounding. Photovoltaic
systems shall comply with one of the
following:
(1) Ungrounded systems shall comply with
690.35.
(2) Grounded two-wire systems shall have
one conductor grounded or be impedance
grounded, and the system shall comply with
690.5.
(3) Grounded bipolar systems shall have
For a photovoltaic power source, one
conductor of a 2-wire system with a
photovoltaic system voltage over 50 volts
and the reference (center tap) conductor
grounded or be impedance grounded, and
the system shall comply with 690.5.
(4)of a bipolar system shall be solidly
grounded or shall use Other methods that
accomplish equivalent system protection in
accordance with 250.4(A) with and that
690.41 System Grounding. Revised.
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utilize equipment listed and identified for
the use shall be permitted to be used.
Exception: Systems complying with 690.35.
690.45 Size of Equipment Grounding
Conductors. Equipment grounding
conductors for photovoltaic PV source and
photovoltaic PV output circuits shall be sized
in accordance with 690.45(A) or (B) 250.122.
Where no overcurrent protective device is
used in the circuit, an assumed overcurrent
device rated at the PV maximum circuit
current shall be used when applying Table
250.122. Increases in equipment grounding
conductor size to address voltage drop
considerations shall not be required. An
equipment grounding conductor shall not be
smaller than 14 AWG.
690.46 Array Equipment Grounding
Conductors. For PV modules equipment
grounding conductors smaller for
photovoltaic modules smaller than 6 AWG
shall comply with 250.120(C).
Where installed in raceways, equipment
grounding conductors and grounding
electrode conductors not larger than 6 AWG
shall be permitted to be solid.
690.47 Grounding Electrode System 690.47 Grounding Electrode System. Revised.
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(B) Direct-Current Systems. If installing a dc
system, a grounding electrode system shall
be provided in accordance with 250.166 for
grounded systems or 250.169 for
ungrounded systems. The grounding
electrode conductor shall be installed in
accordance with 250.64.
A common dc grounding-electrode
conductor shall be permitted to serve
multiple inverters. The size of the common
rounding electrode and the tap conductors
shall be in accordance with 250.166. The tap
conductors shall be connected to the
common grounding-electrode conductor by
exothermic welding or with connectors listed
as grounding and bonding equipment in such
a manner that the common grounding
electrode conductor remains without a splice
or joint.
An ac equipment grounding system shall be
permitted to be used for equipment
grounding of inverters and other equipment
and for the ground-fault detection reference
for ungrounded PV systems.
(C) Systems with Alternating-Current and
Direct-
Current Grounding Requirements.
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(2) Common Direct-Current and Alternating-
Current
Grounding Electrode. A dc grounding
electrode conductor of the size specified by
250.166 shall be run from the marked dc
grounding electrode connection point to the
ac grounding electrode. Where an ac
grounding electrode is not accessible, the dc
grounding electrode conductor shall be
connected to the ac grounding electrode
conductor in accordance with 250.64(C)(1) or
250.65(C)(2) or by using a conductor listed
for grounding and bonding. This dc
grounding electrode conductor shall not be
used as a substitute for any required ac
equipment grounding conductors.
(3) Combined Direct-Current Grounding
Electrode Conductor and
Alternating-Current Equipment
Grounding Conductor. An unspliced,
or irreversibly spliced, combined
grounding conductor shall be run
from the marked dc grounding
electrode conductor connection point
along with the ac circuit conductors
to the grounding busbar in the
associated ac equipment. This
combined grounding conductor shall
be the larger of the sizes specified by
250.122 or 250.166 and shall be
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installed in accordance with
250.64(E). For ungrounded systems,
this conductor shall be sized in
accordance with 250.122 and shall
not be required to be larger than the
largest ungrounded phase conductor.
(E) Additional Auxillary Electrodes for
Array Grounding. New section.
690.53 Direct-Current Photovoltaic Power
Source. A
permanent label for the direct-current
photovoltaic PV power source indicating
items (1) through (5) shall be provided by the
installer at the photovoltaic PV disconnecting
means:
(1) Rated maximum power-point current
(2) Rated maximum power-point voltage
(3) Maximum system voltage Informational
Note to (3): See 690.7(A) for maximum
photovoltaic system voltage.
(4) Maximum circuit Short-circuit current.
Where the PV power source has multiple
outputs, 690.53(1) and (4) shall be specified
for each output.
(5) Maximum rated output current of the
charge controller (if installed)
690.53 Direct-Current Photovoltaic Power
Source. A
permanent label for the direct-current dc PV
power source indicating items (1) through (5) (3)
shall be provided by the installer at the dc PV
system disconnecting means and at each dc
equipment disconnecting means required by
690.15. Where a disconnecting means has more
than one dc PV power source, the values in
690.53(1) through (3) shall be specified for each
source.
(1) Rated Maximum voltage power-point current
(2) Rated Maximum circuit current power-point
voltage
(3) Maximum rated output current of the charge
controller or dc-to-dc converter (if installed)
system voltage Informational Note to (3): See
690.7(A) for maximum photovoltaic system
voltage.
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(4) Maximum circuit current. Where the PV power
source has multiple outputs, 690.53(1) and (4)
shall be specified for each output.
(5) Maximum rated output current of the charge
controller (if installed)
690.56 Identification of Power Sources.
(A) Facilities with Stand-Alone Systems. Any
structure
or building with a photovoltaic PV power
system that is not connected to a utility
service source and is a stand-alone system
shall have a permanent plaque or directory
installed on the exterior of the building or
structure at a readily visible location
acceptable to the authority having
jurisdiction. The plaque or directory shall
indicate the location of system disconnecting
means and that the structure contains a
stand-alone electrical power system. The
marking shall be in accordance with
690.31(G).
(B)Facilities with Utility Services and PV
Systems. Buildings or structures with both
utility service and a photovoltaic PV system
shall have a permanent plaque or directory
providing the location of the service
disconnecting means and the photovoltaic
690.56 Identification of Power Sources.
(C)(1) Rapid Shutdown Type. New subsection.
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PV system disconnecting means if not
located at the same location. The warning
sign(s) or label(s) shall comply with
110.21(B).
(C) Facilities with Rapid Shutdown. New
section.
Figure 690.56(C)(1)(a) Label for PV System that
Shut Down the Array and the Conductors Leaving
the Array. New figure.
Figure 690.56(C)(1)(b) Label for PV Systems that
Shut Down the Conductors Leaving the Array
Only. New figure.
690.59 Connection to Other Sources. New
section.
690.71 Installation.
(B) Dwellings.
(1) Operating Voltage. Storage batteries for
dwellings shall have the cells connected so as
to operate at a voltage of 50 volts, nominal,
or less less than 50 volts nominal. Lead-acid
storage batteries for dwellings shall have no
more than twenty-four 2-volt cells
connected in series (48- volts nominal).
Exception: Where live parts are not
accessible during routine battery
690.71 Installation General. New section.
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maintenance, a battery system voltage in
accordance with 690.7 shall be permitted.
(H) Disconnects and Overcurrent Protection.
New section.
IX. Systems over 600 1000 Volts
690.80 General. Solar photovoltaic systems
with a maximum system voltage over 600
1000 volts dc shall comply with Article 490
and other requirements applicable to
installations rated over 600 1000 volts.
690.81 Listing. New section.
X. Electric Vehicle Charging.
690.90 General. New section.
690.91 Charging Equipment. New section.
ARTICLE 694
Small Wind Electric Systems
ARTICLE 694
Wind Electric Systems
694.7 Installation.
(A) Small Wind Electric Systems. A Small
wind electric system(s) shall be permitted to
supply a building or other structure in
694.7 Installation.
(B) Equipment. Wind electric systems shall be
listed and labeled or field labeled for the
application. Wind electric systems undergoing
evaluation for the type certification and listing
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addition to other sources of supply any
services of another electricity supply system.
(B) Equipment. Inverters used in small Wind
electric systems shall be identified and listed
and labeled for the application.
(E) Receptacles. A receptacle shall be
permitted to be supplied by a small wind
electric system branch or feeder circuit for
maintenance or data acquisition use.
Receptacles shall be protected with an
overcurrent device with a rating not to
exceed the current rating of the receptacle.
All 125-volt, single-phase, 15- and 20-ampere
receptacles installed for maintenance of the
wind turbine shall have ground-fault circuit-
interrupter protection for personnel.
(F)Metal or Nonmetallic Poles or Towers
Supporting Wind Turbines Used as a
Raceway. New section.
shall be permitted to be operated in a controlled
location with access limited to qualified
personnel.
(F) Metal or Nonmetallic Poles or Towers
Supporting Wind Turbines Used as a Raceway.
(G) Working Clearances. New section.
Table 694.7 Working Spaces. New table.
694.23 Turbine Shutdown. New section.
694.30 Permitted Methods.
(B) Flexible Cords and Cables. Flexible cords
and cables, where used to connect the
moving parts of turbines or where used for
ready removal for maintenance and repair,
shall comply with Article 400 and shall be of
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a type identified as hard service cord or
portable power cable, shall be suitable for
extra-hard usage, shall be listed for outdoor
use, and shall be water resistant. Cables
exposed to sunlight shall be sunlight
resistant. Flexible, fine-stranded cables shall
be terminated only with terminals, lugs,
devices, or connectors in accordance with
110.14(A).
(C) Direct-Current Turbine Output Circuits
Inside a
Building. Direct-current turbine output
circuits installed inside a building or
structure shall be enclosed in metal
raceways or installed in metal enclosures, or
run in Type MC metal-clad cable that
complies with 250.118(10), from the point of
penetration of the surface of the building or
structure to the first readily accessible
disconnecting means.
694.40 Equipment Grounding.
(A) General. Exposed non–current-carrying
metal parts of towers, turbine nacelles, other
equipment, and conductor enclosures shall
be grounded in accordance with Parts IV, V,
and VI of Article 250. connected to an
equipment grounding conductor in
accordance with 250.134 or 250.136(A),
regardless of voltage. Attached metal parts,
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such as turbine blades and tails that are not
likely to become energized, have no source
of electrical energization, shall not be
required to be grounded or bonded
connected to equipment grounding
conductors.
(B) Guy Wires. Guy wires used to support
turbine towers
shall not be required to be connected to an
equipment grounding conductor or to
comply with the requirements of 250.110.
Grounding of metallic guy wires may be
required by lightning codes. See
694.40(C)(4).
(C) (B) Tower Grounding and Bonding.
(1) Auxiliary Electrodes Grounding
Electrodes and Grounding Electrode
Conductors. A wind turbine tower shall be
connected a grounding electrode system. to
one or more auxiliary electrodes to limit
voltages
imposed by lightning. Auxiliary electrodes
shall be permitted to be installed in
accordance with 250.54. Electrodes that are
part of the tower foundation and meet the
requirements for concrete encased
electrodes in accordance with 250.52(A)(3)
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shall be acceptable. A grounded metal tower
support shall be considered acceptable
where meeting the requirements of
250.136(A). Where installed in close
proximity to galvanized foundation or tower
anchor components, galvanized grounding
electrodes shall be used.
(2) Equipment Grounding Bonding
Conductor. An Equipment grounding
conductor(s) or supply-side bonding
jumpers, as applicable, shall be required
between turbines, towers, and the premises
grounding system in accordance with
250.110 Parts V and VI of Article 250.
(3) Tower Grounding Connections.
Equipment grounding conductors and
grounding electrode conductors, where
used, shall be connected to the metallic
towers using listed means. by exothermic
welding, listed lugs, listed pressure
connectors, listed clamps, or other listed
means. Devices, such as connectors and lugs,
shall be suitable for the material of the
conductor and the structure to which the
devices are connected. Where practicable,
contact of dissimilar metals shall be avoided
anywhere in the system to eliminate the
possibility of galvanic action and corrosion.
All mechanical elements used to terminate
these conductors shall be accessible.
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(4) Guy Wires. Guy wires used to support
turbine towers shall not be required to be
connected to an equipment grounding or
bonding conductor or to comply with the
requirements of 250.110.
Lightning Protection Systems. Auxiliary
electrodes and grounding electrode
conductors shall be permitted to act as
lightning protection system components
where meeting applicable requirements. If
separate, the tower lightning protection
system grounding electrodes shall be bonded
to the tower auxiliary grounding electrode
system. Guy wires used as lightning
protection system grounding electrodes shall
not be required to be bonded to the tower
auxiliary grounding electrode system.
IX. Systems over 600 1000 Volts
694.80 General. Small wind electric systems
with a maximum system voltage exceeding
600 1000 volts ac or dc shall comply with
Article 490 and other requirements
applicable to installations rated over 600
1000 volts.
ARTICLE 695 Fire Pumps ARTICLE 695 Fire Pumps
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695.1 Scope.
(B) Not Covered. This article does not cover
the following:
(2) The installation pf pressure maintenance
(jockey or makeup) pumps
(3) Transfer equipment upstream of the fire
pump transfer switch(es).
695.3 Powers Source(s) for Electric Motor-
Driven Fire Pumps.
(F) Transfer of Power. New section.
(1) Power Source Selection. New section.
(2) Overcurrent Direct Selection. New
section.
695.4 Continuity of Power.
(A) Direct Connection. The supply
conductors shall directly connect the power
source to either a listed fire pump controller
or listed combination fire pump controller
and power transfer switch, or a listed fire
pump power transfer switch.
695.4 Continuity of Power.
(B)(2) (1) Overcurrent protective device(s) shall be
rated to carry indefinitely the sum of the locked-
rotor current of the largest fire pump motor and
the pressure maintenance pump motor(s) and the
full-load current all of the other fire pump
accessory equipment when connected to this
power supply. Where the locked-rotor current
value does not correspond to a standard
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(B) Connection Through Disconnecting
Means and Overcurrent Device.
(2) Overcurrent Device Selection.
Overcurrent devices shall comply with (a) or
(b).
(a) Individual Sources. Overcurrent
protection for individual sources shall
comply with 695.4(B)(2)(a)(1) or (2).
(1) The Overcurrent protective device(s) shall
be rated to carry indefinitely the sum of the
locked-rotor current of the largest fire pump
motor(s) and the pressure maintenance
pump motor(s) and the full-load current all
of the associated other fire pump accessory
equipment when connected to this power
supply. Where the locked-rotor current value
does not correspond to a standard
overcurrent device size, the next standard
overcurrent device size shall be used in
accordance with 240.6. The requirement to
carry the locked-rotor currents indefinitely
shall not apply to conductors or devices
other than overcurrent devices in the fire
pump motor circuit(s). [20:9.2.3.4]
(2) Overcurrent protection shall be provided
ba an assembly listed for fire pump service
and complying with the following:
overcurrent device size, the next standard
overcurrent device size shall be used in
accordance with 240.6. The requirement to carry
the locked-rotor currents indefinitely shall not
apply to conductors or devices other than
overcurrent devices in the fire pump motor
circuit(s). The requirement to carry the locked
motor currents indefinitely shall not apply to
feeder overcurrent protection devices installed in
accordance with 695.3(C). [20:9.2.3.4]
(B)(3) Disconnecting Means. Add-
Exception to 695.4(B)(3)(a): For a multibuilding
campus-style complex(s) installed under the
provisions of 695.3(C), only the requirements in
695.4(B)(3)(a)(2) shall apply for normal power
source disconnects.
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a. The overcurrent protection device
shall not open within 2 minutes at
600 percent of the full-load current of
the fire pump motor(s).
b. The overcurrent protection device
shall not open with a re-start
transient of 24 times the full-load of
the fire pump motor(s).
c. The overcurrent protection device
shall not open within 10 minutes at
300 percent of the full-load current of
the fire pump operation.
d. The trip point fir circuit breakers
shall not be field adjustable.
[20:9.2.3.4.1]
(3) Disconnecting Means. All disconnecting
devices that are unique to the fire pump
loads shall comply with items (a) through (e).
(a) Features and Location — Normal Power
Source.
The disconnecting means for the normal
power source shall comply with all of the
following: [20:9.2.3.1]
(1) Be identified as suitable for use as service
equipment
(2) Be lockable in the closed position. The
provision for locking or adding a lock to the
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disconnecting means shall be installed on or
at the switch or circuit breaker used as the
disconnecting means and shall remain in
place with or without the lock installed.
(3) Not be located within the same
enclosure, panelboard, switchboard, or
motor control center, with of without
common bus, equipment that supplies feeds
loads other than the fire pump.
(4) Be located sufficiently remote from other
building or other fire pump source
disconnecting means such that inadvertent
operation at the same time would be
unlikely.
(b) Features and Location — On-Site Standby
Generator. The disconnecting means for an
on-site standby generator(s) used as the
alternate power source shall be installed in
accordance with 700.10(B)(5) for emergency
circuits and shall be lockable in the closed
position. The provision for locking or adding
a lock to the disconnecting means shall be
installed on or at the switch or circuit
breaker used as the disconnecting means
and shall remain in place with or without the
lock provided.
695.6 Power Wiring.
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(D) Pump Wiring. All wiring from the
controllers to the pump motors shall be in
rigid metal conduit, intermediate metal
conduit, electrical metallic tubing, liquidtight
flexible metal conduit, or liquidtight flexible
nonmetallic conduit Type LFNC-B, listed Type
MC cable with an impervious covering, or
Type MI cable. Electrical connections at
motor terminal boxes shall be made with a
listed means of connection. Twist-on,
insulation-piercing-type, and soldered wire
connections shall not be permitted to be
used for this purpose.
695.14 Control Wiring.
(F) Generator Control Wiring Methods. Add-
The integrity of the generator control wiring shall
be continuously monitored. Loss of integrity of
the remote start circuit(s) shall initiate visual and
audible annunciation of generator malfunction at
the generator local and remote annunciator(s)
and start the generator(s).
ARTICLE 700 Emergency Systems ARTICLE 700 Emergency Systems
700.2 Definitions.
Branch Circuit Emergency Lighting Transfer
Switch. New definition.
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Luminaire, Directly Controlled. New definition.
Temporary Source of Power for Maintenance or
Repair of the Alternate Source of Power. New
definition.
Figure 700.3(F). New figure.
700.5 Transfer Equipment.
(E) Documentation. New subsection.
(D) Ground Fault. Add-
For systems with multiple emergency sources
connected to a paralleling bus, the ground fault
sensor shall be permitted to be at an alternate
location.
700.8 Surge Protection. New section.
700.10 Wiring, Emergency System.
B) Wiring. Wiring of two or more emergency
circuits supplied from the same source shall
be permitted in the same raceway, cable,
box, or cabinet. Wiring from an emergency
source or emergency source distribution
overcurrent protection to emergency loads
shall be kept entirely independent of all
other wiring and equipment, unless
otherwise permitted in 700.10(B) (1) through
(5):
700.10 Wiring, Emergency System.
(A) Identification. Emergency circuits shall be
permanently marked so they will be readily
identified as a component of an emergency circuit
or system by the following methods:
(1) All boxes and enclosures (including transfer
switches, generators, and power panels) for
emergency circuits shall be permanently marked
as a component of an emergency circuit or
system. they will be readily identified as a
component of an emergency circuit or system.
(2) Where boxes and enclosures are not
encountered, exposed cable or raceway systems
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(5) Wiring from an emergency source to
supply emergency and other loads any
combination of emergency, legally required,
or optional loads in accordance with (a), (b),
(c), and (d):
a. From Separate vertical switchgear sections
or switchboard sections, with or without a
common bus, or from individual disconnects
mounted in separate enclosures shall be
used to separate emergency loads from all
other loads.
b. The common bus of separate sections of
the switchgear, or separate sections of the
switchboard or the individual enclosures
shall be permitted to be supplied by single or
multiple feeders without overcurrent
protection at the source.
Exception to (5)(b): Overcurrent protection
shall be permitted at the source or for the
equipment, provided the overcurrent
protection complies with the requirements of
700.27 700.28.
c. Emergency circuits Legally required and
optional standby circuits shall not originate
from the same vertical switchgear section,
vertical switchboard section, panelboard
enclosure, or individual disconnect enclosure
as emergency other circuits.
shall be permanently marked to be identified as a
component of an emergency circuit or system, at
intervals not to exceed 7.6 m (25 ft).
(B) Wiring. Wiring of two or more emergency
circuits supplied from the same source shall be
permitted in the same raceway, cable, box, or
cabinet. Wiring from an emergency source or
emergency source distribution overcurrent
protection to emergency loads shall be kept
entirely independent of all other wiring and
equipment, unless otherwise permitted in
700.10(B)(1) through (5):
(1) Wiring from the normal power source located
in transfer equipment enclosures
(2) Wiring supplied from two sources in exit or
emergency luminaires
(3) Wiring from two sources in a listed load
control relay
supplying exit or emergency luminaires, or in a
common junction box, attached to exit or
emergency
luminaires
(4) Wiring within a common junction box attached
to unit
equipment, containing only the branch circuit
supplying
the unit equipment and the emergency circuit
supplied
by the unit equipment
(5) Wiring from an emergency source to supply
emergency and other (nonemergency) loads in
accordance with (a), (b), (c), and (d):
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d. It shall be permissible to utilize single or
multiple
feeders to supply distribution equipment
between an emergency source and the point
where the emergency combination of
emergency, legally required, or optional
loads are separated from all other loads.
(D) Fire Protection. Emergency systems shall
meet the additional requirements in (D)(1)
through (D)(3) in assembly occupancies for
not less than 1000 persons or in buildings
above 23 m (75 ft) in height with any of the
following occupancy classes: assembly,
educational, residential, detention and
correctional, business, and mercantile.
a. Separate vertical switchgear sections or
switchboard sections, with or without a common
bus, or individual disconnects mounted in
separate enclosures shall be used to separate
emergency loads from all other loads.
b. The common bus of separate sections of the
switchgear, separate sections of the switchboard
or the individual enclosures shall be either of the
following:
(i) permitted to be Supplied by single or multiple
feeders without overcurrent protection at the
source.
(ii) Supplied by single or multiple feeders with
overcurrent protection, provided that the
overcurrent protection that is common to an
emergency system and any non-emergency
system(s) is selectively coordinated with the next
downstream overcurrent protection device in the
nonemergency system(s)
c. Emergency circuits shall not originate from the
same vertical switchgear section, vertical
switchboard section, panelboard enclosure, or
individual disconnect enclosure as other circuits.
d. It shall be permissible to utilize single or
multiple feeders to supply distribution equipment
between an emergency source and the point
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where the emergency loads are separated from
all other loads.
(D) Fire Protection. Emergency systems shall
meet the
additional requirements in (D)(1) through (D)(3) in
the following occupancies:
(1) Assembly occupancies for not less than
1000 persons
(2) or in Buildings above 23 m (75 ft) in
height with any of the following
occupancy classes: assembly,
educational, residential, detention and
correctional, business, and mercantile.
(3) Health care occupancies where persons
are not capable of self preservation.
(4) Educational occupancies with more than
300 occupants.
(1) Feeder-Circuit Wiring. Feeder-circuit wiring
shall meet one of the following conditions:
(1) The cable or raceway is Be installed in spaces
or areas that are fully protected by an approved
automatic fire suppression system
(2) The cable or raceway is protected by Be a
listed electrical circuit protective system with a
minimum
2-hour fire rating
(3) The cable or raceway is listed fire-resistive
cable system Be protected by a listed thermal
barrier system for electrical system components
with a minimum 2-hour fire rating
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(4) The cable or raceway is protected by a listed
fire-rated assembly that has a minimum fire rating
of 2 hours and contains only emergency circuits.
Be protected by a listed fire-rated assembly that
has a minimum fire rating of 2 hours and contains
only emergency wiring circuits.
(5) Be encased in a minimum of 50 mm (2 in.) of
concrete
(3) Generator Control Wiring. Control conductors
installed between the transfer equipment and the
emergency generator shall be kept entirely
independent of all other wiring and shall meet the
conditions of 700.10(D)(1). The integrity of the
generator control wiring shall be continuously
monitored. Loss of integrity of the remote start
circuits shall initiate visual and audible
annunciation of generator malfunction at the
generator local and remote annunciator(s) and
start the generator(s).
700.12 General Requirements.
(B) Generator Set.
(6) Outdoor Generator Sets. Where an
outdoor housed generator set is equipped
with a readily accessible disconnecting
means in accordance with 445.18, and the
disconnecting means is located within sight
of the building or structure supplied, an
additional disconnecting means shall not be
required where ungrounded conductors
serve or pass through the building or
700.12 General Requirements. Current supply
shall be such that, in the event of failure of the
normal supply to, or within, the building or group
of buildings concerned, emergency lighting,
emergency power, or both shall be available
within the time required for the application but
not to exceed 10 seconds. The supply system for
emergency purposes, in addition to the normal
services to the building and meeting the general
requirements of this section, shall be one or more
of the types of systems described in 700.12(A)
through (E). Unit equipment in accordance with
700.12(F) shall satisfy the applicable
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structure. Where the generator supply
conductors terminate at a disconnecting
means in or on a building or structure, the
disconnecting means shall meet the
requirements of 225.36.
Exception: For installations under single
management, where conditions of
maintenance and supervision ensure that
only qualified persons will monitor and
service the installation and where
documented safe switching procedures are
established and maintained for
disconnection, the generator set
disconnecting means shall not be required to
be located within sight of the building or
structure served.
(D) Separate Service. Where approved by
the authority having jurisdiction as suitable
for use as an emergency source of power, an
additional service shall be permitted. This
service shall be in accordance with the
applicable provisions of Article 230 and the
following additional requirements:
(1) Separate overhead service conductors,
service drops, underground service
conductors, or service laterals shall be
installed.
(2) The service conductors for the separate
service shall be installed sufficiently remote
requirements of this article.
In selecting an emergency source of power,
consideration
shall be given to the occupancy and the type of
service to be rendered, whether of minimum
duration, as for evacuation of a theater, or longer
duration, as for supplying emergency power and
lighting due to an indefinite period of current
failure from trouble either inside or outside the
building.
Equipment shall be designed and located so as to
minimize the hazards that might cause complete
failure due to flooding, fires, icing, and vandalism.
Equipment for sources of power as described in
700.12(A) through (E) shall be installed either in
spaces fully protected by approved automatic fire
suppression systems (sprinklers, carbon dioxide
systems and so forth) or in spaces with a 1-hour
fire rating where located within the following:
(1) Assembly occupancies for greater more
than 1000 persons or in
(2) Buildings above 23 m (75 ft) in height with
any of the following occupancy classes —
assembly, educational, residential,
detention and correctional, business, and
mercantile.
(3) Health care occupancies where persons
are not capable of self preservation
(4) Educational occupancies with more than
300 occupants
—shall be installed either in spaces fully protected
by approved automatic fire suppression systems
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electrically and physically from any other
service conductors to minimize the
possibility of simultaneous interruption of
supply.
(F) Unit Equipment.
(1) Components of Unit Equipment.
Individual unit equipment for emergency
illumination shall consist of the following:
(1) A rechargeable battery
(2) A battery charging means
(3) Provisions for one or more lamps
mounted on the equipment, or shall be
permitted to have terminals for remote
lamps, or both
(4) A relaying device arranged to energize
the lamps automatically upon failure of the
supply to the unit equipment
(2) Installation of Unit Equipment. Unit
equipment shall be installed in accordance
with 700.12(F)(2)(1) through (6).
(1) The batteries shall be of suitable rating
and capacity to supply and maintain at not
less than 871⁄2 percent of the nominal
battery voltage for the total lamp load
associated with the unit for a period of at
least 11⁄2 hours, or the unit equipment shall
(sprinklers, carbon dioxide systems, and so forth)
or in spaces with a 1-hour fire rating.
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supply and maintain not less than 60 percent
of the initial emergency illumination for a
period of at least 11⁄2 hours. Storage
batteries, whether of the acid or alkali type,
shall be designed and constructed to meet
the requirements of emergency service.
(2) Unit equipment shall be permanently
fixed in place (i.e., not portable) and shall
have all wiring to each unit installed in
accordance with the requirements of any of
the wiring methods in Chapter 3. Flexible
cord-and-plug connection shall be permitted,
provided that the cord does not exceed 900
mm (3 ft) in length.
(3)The branch circuit feeding the unit
equipment shall be the same branch circuit
as that serving the normal lighting in the
area and connected ahead of any local
switches. The branch circuit that feeds unit
equipment shall be clearly identified at the
distribution panel. Emergency luminaires
that obtain power from a unit equipment
and are not part of the unit equipment shall
be wired to the unit equipment as required
by 700.10 and by one of the wiring methods
of Chapter 3.
Exception No. 1: In a separate and
uninterrupted area
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supplied by a minimum of three normal
lighting circuits that are not part of the
multiwire branch circuit, a separate branch
circuit for unit equipment shall be permitted
if it originates from the same panelboard as
that of the normal lighting circuits and is
provided with a lock-on feature.
(4) The branch circuit that feed unit
equipment shall be clearly identified
at the distribution panel.
(5) Emergency luminaires that obtain
power from a unit equipment and are
not part of the unit equipment shall
be wired to the unit equipment as
required by 700.10 and by one of the
wiring methods of Chapter 3.
(6) Exception No. 2: Remote heads
providing lighting for the exterior of
an exit door shall be permitted to be
supplied by the unit equipment
serving the area immediately inside
the exit door.
700.16 Emergency Illumination. Emergency
illumination shall include all required means
of egress lighting, illuminated exit signs, and
all other lights specified as necessary to
provide required illumination.
Emergency lighting systems shall be
designed and installed so that the failure of
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any individual lighting element, such as the
burning out of a lamp, cannot leave in total
darkness any space that requires emergency
illumination.
Where high-intensity discharge lighting such
as high and low-pressure sodium, mercury
vapor, and metal halide is used as the sole
source of normal illumination, the
emergency lighting system shall be required
to operate until normal illumination has
been restored.
Where an emergency system is installed,
emergency illumination shall be provided in
the area of the disconnecting means
required by 225.21 and 225.70, as
applicable, where the disconnecting means
are installed indoors.
Exception: Alternative means that ensure
that the emergency lighting illumination level
is maintained shall be permitted.
700.19 Multiwire Branch Circuits. New
section.
700.23 Dimmer and Relay Systems. A
dimmer or relay system containing more
than one dimmer or relay and listed for use
in emergency systems shall be permitted to
be used as a control device for energizing
emergency lighting circuits. Upon failure of
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normal power, the dimmer or relay system
shall be permitted to selectively energize
only those branch circuits required to
provide minimum emergency illumination.
All branch circuits supplied by the dimmer or
relay system cabinet shall comply with the
wiring methods of Article 700.
700.24 Directly Controlled Luminaires. New
section inserted.
700.26 700.27 Ground-Fault Protection of
Equipment. The alternate source for
emergency systems shall not be required to
have ground-fault protection of equipment
with automatic disconnecting means.
Ground-fault indication of the emergency
source shall be provided in accordance with
700.6(D) if ground-fault protection of
equipment with automatic disconnecting
means is not provided.
700.27 700.28 Selective Coordination.
Emergency system(s) overcurrent devices
shall be selectively coordinated with all
supply side overcurrent protective devices.
Selective coordination shall be selected by a
licensed professional engineer or other
qualified persons engaged primarily in the
design, installation, or maintenance of
electrical systems. The selection shall be
documented and made available tom those
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authorized to design install, inspect,
maintain, and operate the system.
Exception: Selective coordination shall not be
required between two overcurrent devices
located in series if no loads are connected in
parallel with the downstream device.
701.5 Transfer Equipment.
(C) Automatic Transfer Switches. Automatic
transfer switches shall be electrically
operated and mechanically held. Automatic
transfer switches, rated 600 1000 VAC and
below, shall be listed for emergency use.
701.5 Transfer Equipment.
(D) Documentation. New section.
701.6 (D) Ground Fault. Add-
For systems with multiple emergency sources
connected to a paralleling bus, the ground fault
sensor shall be permitted at an alternate location.
701.12 General Requirements.
(B) Generator Set.
(5) Outdoor Generator Sets. Where an
outdoor housed generator set is equipped
with a readily accessible disconnecting
means in accordance with 445.18, and the
disconnecting means is located within sight
of the building or structure supplied, an
additional disconnecting means shall not be
required where ungrounded conductors
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serve or pass through the building or
structure. Where the generator supply
conductors terminate at a disconnecting
means in or on a building or structure, the
disconnecting means shall meet the
requirements of 225.36.
(701) Separate Service. Where approved, a
separate service shall be permitted as a
legally required source of standby power.
This service shall be in accordance with the
applicable provisions of Article 230, with
separate service drop or lateral or a separate
set of overhead or underground service
conductors sufficiently remote electrically
and physically from any other service to
minimize the possibility of simultaneous
interruption of supply from an occurrence in
another service.
701.26 Ground-Fault Protection of
Equipment. The alternate source for legally
required standby systems shall not be
required to have ground-fault protection of
equipment with automatic disconnecting
means. Ground-fault indication of the legally
required standby source shall be provided in
accordance with 701.6(D) if ground-fault
protection of equipment with automatic
disconnecting means is not provided.
701.27 Coordination. Legally required
standby system(s) overcurrent devices shall
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be selectively coordinated with all supply-
side overcurrent protective devices.
Selective coordination shall be selected by a
licensed professional engineer or other
qualified persons engaged primarily in the
design, installation, or maintenance of
electrical systems. The selection shall be
documented and made available to those
authorized to design, install, inspect,
maintain, and operate the system.
Exception: Selective coordination shall not be
required between two overcurrent devices
located in series if no loads are connected in
parallel with the downstream device.
ARTICLE 702 Optional Standby Systems ARTICLE 702 Optional Standby Systems
702.5 Transfer Equipment. Add-
The short-circuit current rating of the transfer
equipment, based on the specific overcurrent
protective device type and settings protecting the
transfer equipment, shall be field marked on the
exterior of the transfer equipment.
702.7 Signs.
(C) Power Inlet. New subsection added.
702.12 Outdoor Generator Sets. 702.12 Outdoor Generator Sets.
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(A) Permanently Installed Generators and
Portable Generators Greater Than 15 kW.
Where an outdoor housed generator set is
equipped with a readily accessible
disconnecting means in accordance with
445.18, and the disconnecting means is
located within sight of the building or
structure supplied, an additional
disconnecting means shall not be required
where ungrounded conductors serve or pass
through
the building or structure. Where the
generator supply conductors terminate at a
disconnecting means in or on a building or
structure, the disconnecting means shall
meet the requirements of 225.36.
(B)Portable Generators 15 kW or Less. New
subsection.
(C) Power Inlets Rated at 100 Amperes or
Greater, for Portable Generators. New
subsection.
ARTICLE 705 Interconnected Electric Power
Production Sources
705.2 Definitions.
Multimode Inverter. New definition.
Table 705.3 Other Articles. Revised.
705.12 Point of Connection.
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(D) Utility-Interactive Inverters.
(1) Dedicated Overcurrent and Disconnect.
Each The source Interconnection of one or
more inverters installed in one system shall
be made at a dedicated circuit breaker or
fusible disconnecting means.
(2) Bus or Conductor Ampere Rating.
Revised.
(6) (5) Fastening. Renumbered.
(6) Wire Harness and Exposed Cable Arc-
Fault Protection. New section.
(7) Inverter Output Connection. Unless the
panelboard is rated not less than the sum of
the ampere ratings of all overcurrent devices
supplying it, a connection in a panelboard
shall be positioned at the opposite (load) end
from the input feeder location or main circuit
location. The bus or conductor rating shall be
sized for the loads connected in accordance
with Article 220. In systems with
panelboards connected in series, the rating
of the first overcurrent device directly
connected to the output of a utility-
interactive inverter(s) shall be used in the
calculations for all busbars and conductors. A
permanent warning label shall be applied to
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the distribution equipment with the
following or equivalent wording:
WARNING
INVERTER OUTPUT CONNECTION
DO NOT RELOCATE THIS
OVERCURRENT DEVICE
705.23 Interactive System Disconnecting Means.
New section.
705.31 Location of Overcurrent Protection.
New section.
705.66 Overcurrent Protection.
(C) Conductor Ampacity. New subsection.
705.100 Unbalanced Interconnections.
(A) Single Phase. Single-phase inverters for
hybrid systems and ac modules in interactive
hybrid systems shall be connected to three-
phase power systems in order to limit
unbalanced voltages to not more than 3
percent. not be connected to 3-phase power
systems unless the interconnected system is
designed so that significant unbalanced
voltages cannot result.
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Part IV. Microgrid Systems. New part and
sections.
ARTICLE 706 Energy Storage Systems. New
article, sections, and subsection.
ARTICLE 708 Critical Operations Power
Systems (COPS)
ARTICLE 708 Critical Operations Power Systems
(COPS)
708.10 Feeder and Branch Circuit Wiring.
(A) Identification.
(1) Boxes and Enclosures. In a building or at
a structure where s critical operations power
system and any other type of power system
are present, all boxes and enclosures
(including transfer switches, generators, and
power panels) for critical operations power
system circuits shall be permanently marked
so they will be readily identified as a
component of the critical operations power
system.
708.10 Feeder and Branch Circuit Wiring.
(A)(2) Receptacle Identification. Add-
Nonlocking-type, 125-volt, 15- and 20-ampere
receptacles supplied from the COPS shall have an
illuminated face or an indicator light to indicate
that there is power to the receptacle.
(2) Fire Protection for Feeders. Feeders shall
meet one of
the following conditions:
(1) The cable or raceway is protected by Be a
listed electrical circuit protective system with a
minimum 2-hour fire rating
(2)The cable or raceway is Be protected by a
listed fire-rated cable system with assembly that
has a
minimum fire rating of 2 hours
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(3) The cable or raceway is protected by a listed
fire-rated assembly that has a minimum fire rating
of 2 hours.
(4) The cable or raceway is Be encased in a
minimum of 50 mm (2 in.) of concrete
708.14 Wiring of HVAC, Fire Alarm, Security,
Emergency
Communications, and Signaling Systems. All
conductors
or cables shall be installed using any of the
metal wiring methods permitted by
708.10©(1) and in addition shall comply with
708.14(1) through (8), as applicable.
(1) All cables for fire alarm, security, signal
signaling systems, and emergency
communications shall be shielded twisted
pair cables or installed to comply with the
performance requirements of the system.
(2) Shields of cables for fire alarm, security,
signal signaling systems, and emergency
communications shall be arranged in
accordance with the manufacturer’s
published installation instructions
continuous.
(7) All cables for fire alarm, security, and
signaling systems shall be riser-rated and
shall be a listed 2-hour electrical circuit
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protective system. Riser emergency
communication cables shall be Type CMR-CI
or shall be riser-rated and shall be a listed 2-
hour electrical circuit protective system.
708.20 Sources of Power.
(F) Generator Set.
(5) Outdoor Generator Sets.
(a) Permanently Installed Generators and
Portable Generators Greater Than 15 kW.
Where an outdoor housed generator set is
equipped with a readily accessible
disconnecting means in accordance with
445.18, and the disconnecting means is
located within sight of the building or
structure supplied, an additional
disconnecting means shall not be required
where ungrounded conductors serve or pass
through the building or structure. Where the
generator supply conductors terminate at a
disconnect means in or on a building or
structure, the disconnecting means shall
meet the requirements of 225.26.
(b) Portable Generators 15 kW or less.
Where a portable generator, rated 15 kW or
less, is installed using a flanged inlet or other
cord- and plug-type connection, a
disconnecting means shall not be required
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where ungrounded conductors serve or pass
through a building or structure.
708.24 Transfer Equipment.
(E) Documentation. New section.
ARTICLE 710 Stand-Alone Systems
710.6 Equipment Approval. New section.
ARTICLE 725 Class 1, Class 2, and Class 3
Remote-Control, Signaling, and Power-
Limited Circuits
725.1 Definitions.
Power-Limited Tray Cable (PLTC). New
definition.
725.3 Other Articles.
(K) Installation of Conductors with Other
Systems. New subsection.
(L) Corrosive, Damp, or Wet Locations. New
section.
725.3 Other Articles.
(C) Ducts, Plenums, and Other Air-Handling
Spaces. Add-
Exception No. 1: Class 2 and Class 3 cables
selected in accordance with Table 725.154 and
installed in accordance with 725.135(B) and
300.22(B), Exception shall be permitted to be
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installed in ducts specifically fabricated for
environmental air.
Exception No. 2: Class 2 and Class 3 cables
selected in accordance with Table 725.154 and
installed in accordance with 725.135(C) shall be
permitted to be installed in other spaces used for
environmental air (plenums).
(M) Cable Routing Assemblies. New section.
(N) Communications Raceways. New section.
725.121 Power Sources for Class 2 and Class 3
Circuits.
(C) Marking. New subsection.
725.135 Installation of Class 2, Class 3, and
PLTC Cables. New section.
725.139 Installation of Conductors of
Different Circuits in the Same Cable,
Enclosure, Cable Tray, Raceway, or Cable
Routing Assembly. Add “raceway and cable
routing assembly”.
725.154 Applications of Listed Class 2, Class
3, and
PLTC Cables. Class 2, Class 3, and PLTC cables
shall comply with any of the requirements
described in 725.154(A) through (I) (C) and
indicated in Table 725.154.
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Table 725.154 Applications of Listed Class 2,
Class 3, and PLTC Cables in Buildings. New
table.
725.170 Listing and Marking of Equipment for
Power and Data Transmission. New Section.
725.179 Listing and Marking of Class 2, Class
3, and
Type PLTC Cables; Communications
Raceways; and Cable Routing Assemblies.
Class 2, Class 3, and Type PLTC Cables, and
nonmetallic signaling raceways and cable
routing assemblies installed as wiring
methods within buildings shall be listed as
being resistant to the spread of fire and
other criteria in accordance with 725.179(A)
through (K) and shall be marked in
accordance with 725.179(L) 725.179(K).
F) Circuit Integrity (CI) Cable or Electrical
Circuit
Protective System. Cables that are used for
survivability of critical Circuits under fire
conditions shall meet either 725.179(F)(1) or
(F)(2) as follows:
(1) Circuit Integrity (CI) Cables. Circuit
Integrity (CI) cables be listed as circuit
integrity (CI) cable. Cables specified in
725.154(A), (B), (D)(1), and (E), and
725.179 Listing and Marking of Class 2, Class 3,
and Type PLTC Cables.
(I) Limited Power (LP) Cables. New section.
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used for survivability of critical
circuits, circuit integrity, shall have
the additional classification using the
suffix “-CI”. Circuit Integrity (CI)
cables shall only be permitted to be
installed in a raceway where
specifically listed and marked as
Cables that are part of a an listed
electrical circuit protective system as
covered in 725.179(F)(2) shall be
considered to meet the requirements
of survivability.
(2) Electrical Circuit Protective System.
New subsection.
(J) (I) Riser Cable Routing Assemblies
Signaling Raceways. Riser cable routing
assemblies signaling raceways shall be listed
as having adequate fire-resistant
characteristics capable of preventing the
carrying of fire from floor to floor.
(K) (J) General-Purpose General-Use Cable
Routing Assemblies Signaling Raceways.
General-use cable routing assemblies
purpose signaling raceways shall be listed as
being resistant to the spread of fire.
ARTICLE 727 Instrumentation Tray Cable: Type
ITC
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727.4 Uses Permitted. Add-
Exception to (5): Where not subject to physical
damage, Type ITC-FR shall be permitted to
transition between cable trays and between cable
trays and utilization equipment or devices for a
distance not to exceed 1.8 m (6 ft) without
continuous support. The cable shall be
mechanically supported where exiting the cable
tray to ensure that the minimum bending radius is
not exceeded.
ARTICLE 728 Fire-Resistive Cable Systems.
New article.
ARTICLE 728 Fire-Resistive Cable Systems
728.5 Installations.
(C) Raceways and Couplings. Add-
The raceway fill for each system shall comply with
the listing requirements for the system and shall
not be greater than the fill permitted in Table 1,
Chapter 9.
ARTICLE 750 Energy Management Systems.
New article.
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ARTCILE 760 Fire Alarm Systems ARTCILE 760 Fire Alarm Systems
760.3 Other Articles.
B) Ducts, Plenums, and Other Air-Handling
Spaces.
Power limited and non-power-limited fire alarm
cables Section 300.22, where installed in ducts or
plenums or other spaces used for environmental
air shall comply with 300.22.
Exception No. 1: Power-limited fire alarm cables
selected in accordance with Table 760.154 and
installed in accordance with 760.135(B) and
300.22(B), Exception shall be permitted to be
installed in ducts specifically fabricated for
environmental air.
Exception No. 2: Power-limited fire alarm cables
selected in accordance with Table 760.154 and
installed in accordance with 760.135(C) shall be
permitted to be installed in other spaces used for
environmental air (plenums).
As permitted in 760.53(B)(1) and (B)(2) and Table
760.154.
(L) Cable Routing Assemblies. New section.
(M) Communications Raceways. New section.
760.24 Mechanical Execution of Work.
(A) General. Fire alarm circuits shall be
installed in a neat workmanlike manner.
Cables and conductors installed exposed on
the surface of ceilings and sidewalls shall be
supported by the building structure in such a
manner that the cable will not be damaged
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by normal building use. Such cables shall be
supported by straps, staples, cable ties,
hangers, or similar fittings designed and
installed so as not to damage the cable. The
installation shall also comply with 300.4(D).
(B) Circuit Integrity (CI) Cable. New
subsection.
760.32 Fire Alarm Circuits Extending Beyond
One Building. Non-power limited fire alarm
circuits and power-limited fire alarm circuits
that extend beyond one building and run
outdoors either shall meet the installation
requirements of Parts II, III, and IV of Article
800 or shall meet the installation
requirements of Part I of Article 300. Non–
power-limited fire alarm circuits that extend
beyond one building and run outdoors shall
meet the installation requirements of Part I
of Article 300 and the applicable sections of
Part I of Article 225.
760.135 Installation of PLFA Cables in
Buildings. New section.
760.139 Installation of Conductors of
Different PLFA Circuits, Class, Class 3, AND
Communications Circuits in the Same Cable,
Enclosure, Cable Tray, Raceway, or Cable
Routing Assembly. Add “raceway and cable
routing assembly”
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760.154 Applications of Listed PLFA Cables.
PLFA cables shall comply with the
requirements described in Table 760.154
either 760.154(A), (B), or (C) or where cable
substitutions are made as shown in
760.154(D) (A). Where substitute cables are
installed, the wiring requirements of Article
760, Parts I and III, shall apply. Types FPLP-CI,
FPLR-CI, and FPL-CI cables shall be permitted
to be installed to provide 2-hour circuit
integrity rated cables.
Table 760.154(A) Cable Substitutions. New
table.
(F) Fire Alarm Circuit Integrity (CI) Cable or
Electrical
Circuit Protective System. Cables that are
used for survivability of critical circuits under
fire conditions shall meet either
760.176(F)(1) or (F)(2) as follows:
(1) Circuit Integrity (CI) Cables. New
section.
(2) Electrical Circuit Protection System.
New section.
be listed as circuit integrity (CI) cable. Cables
specified in 760.176(C), (D), and (E), and
used for circuit integrity shall have the
additional classification using the suffix “-CI.”
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Cables that are part of a listed electrical
circuit protective system shall be considered
to meet the requirements of survivability.
760.176 Listing and Marking of NPLFA Cables.
Add-
Non-power-limited fire alarm cables shall have a
temperature rating of not less than 600C (1400F).
(G)NPLFA Cable Marking. Add-
Temperature rating shall be marked on the jacket
of NPLFA cables that have a temperature rating
exceeding 600C (1400F). The jacket of NPLFA
cables shall be marked with the conductor size.
760.179 Listing and marking of PLFA Cables
and Insulated Continuous Line-Type Fire
Detectors.
G) Fire Alarm Circuit Integrity (CI) Cable or
Electrical
Circuit Protective System. Cables used for
survivability of critical circuits under fire
conditions shall meet either 760.179(G)(1) or
(G)(2) as follows:
(1) Circuit Integrity (CI) Cables. New
section.
(2) Electrical Circuit Protective System.
New section.
760.179 Listing and marking of PLFA Cables and
Insulated Continuous Line-Type Fire Detectors.
(C) Ratings. Add-
The cable shall have a temperature rating of not
less than 600C (1400F).
(I)Cable Marking. Add-
Temperature ratings shall be marked on the
jacket of PLFA cables that have a temperature
rating exceeding 600C (1400F). The jacket of PLFA
cables shall be marked with the conductor size.
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be listed as circuit integrity (CI) cable. Cables
specified in 760.179(D), (E), (F), and (H) and
used for circuit integrity shall have the
additional classification using the suffix “-CI.”
Cables that are part of a listed electrical
circuit protective system shall be considered
to meet the requirements of survivability.
ARTICLE 770 Optical Fiber Cables and
Runways
ARTICLE 770 Optical Fiber Cables and Runways
770.2 Definitions.
Electrical Circuit Protective System. New
definition.
Innerduct. New definition.
770.3 Other Articles.
(B) Cables in Ducts for Dust, Loose Stock, or
Vapor Removal. New subsection inserted.
770.12 Innerduct for Optical Fiber Cables.
Listed plenum
optical fiber communications raceway, listed
riser optical fiber raceway, or and listed
general-purpose optical fiber
communications raceway selected in
accordance with the provisions of 770.154
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Table 800.154(b) shall be permitted to be
installed as innerduct in any type of listed
raceway permitted in Chapter 3.
770.24 Mechanical Execution of Work.
Optical fiber cables shall be installed in a
neat and workmanlike manner. Cables
installed exposed on the surface of ceilings
and sidewalls shall be supported by the
building structure in such a manner that the
cable will not be damaged by normal
building use. Such cables shall be secured by
hardware including straps, staples, cable ties,
hangers, or similar fittings designed and
installed so as not to damage the cable. The
installation shall also conform with 300.4(D)
through (G) and 300.11. Nonmetallic cable
ties and other nonmetallic cable accessories
used to secure and support cables in other
spaces used for environmental air (plenums)
shall be listed as having low smoke and heat
release properties.
770.26 Spread of Fire or Products of
Combustion. Installations of optical fiber
cables and communications raceways in
hollow spaces, vertical shafts, and ventilation
or air-handling ducts shall be made so that
the possible spread of fire or products of
combustion will not be substantially
increased. Openings around penetrations of
optical fiber cables and communications
raceways
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through fire-resistant–rated walls, partitions,
floors, or ceilings shall be firestopped using
approved methods to maintain the fire
resistance rating.
770.44 Overhead (Aerial) Optical Fiber Cables.
New section and subsections.
770.47 Underground Optical Fiber Cables
Entering Buildings. New section.
770.48 Unlisted Cables and Raceways
Entering Buildings.
(B) Nonconductive Cables in Raceway.
Unlisted nonconductive outside plant optical
fiber cables shall be permitted to enter the
building from the outside and shall be
permitted to be installed in any of the
following:
(1) Intermediate metal conduit (IMC)
(2) Rigid metal conduit (RMC)
(3) Rigid polyvinyl chloride conduit (PVC)
(4) Electrical metallic tubing (EMT)
run in raceway systems installed in
compliance with any of the following articles
in Chapter 3: Article 342, Intermediate Metal
Conduit: Type IMC; Article 344, Rigid Metal
Conduit: Type RMC; Article 352, Rigid
Polyvinyl Chloride Conduit: Type PVC; and
770.48 Unlisted Cables and Raceways Entering
Buildings.
(A) Conductive and Nonconductive Cables. Add-
The point of entrance shall be permitted to be
extended from the penetration of the external
wall or floor slab by continuously enclosing the
entrance optical fiber cables in rigid metal conduit
(RMC) or intermediate metal conduit (IMC) to the
point of emergence.
(B)Nonconductive Cables in Raceway. Add-
Unlisted nonconductive outside plant cables
installed in rigid polyvinyl chloride conduit (PVC)
or electrical metallic tubing (EMT) shall not be
permitted to be installed in risers, ducts used for
environmental air, plenums used for
environmental air, and other spaces used for
environmental air.
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Article 358, Electrical Metallic Tubing: Type
EMT.
770.100 Entrance Cable Bonding and
Grounding.
(4) Length. New section inserted.
(5) (6) Physical Damage Protection. Bonding
conductors Where necessary, the bonding
conductor and grounding electrode
conductor shall be protected where exposed
to guarded from physical damage. Where
the bonding conductor or grounding
electrode conductor these conductors are
installed in a metal raceway, both ends of
the raceway shall be bonded to the
contained conductors or to the same
terminal or electrode to which the bonding
conductor or grounding electrode conductor
is connected conductor(s) is (are) connected.
770.110 Raceways and Cable Routing
Assemblies for Optical Fiber Cables.
(A) Types of Raceways. Optical fiber cables
shall be permitted to be installed in any
raceway that complies with either (A)(1) or
(A)(2) and in cable routing assemblies
installed in compliance with 770.110(C).
(2) Other Permitted Communications
Raceways. Optical fiber cables shall be
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permitted to be installed in listed plenum
communication raceways, listed riser
communications raceways, and listed
general-purpose communications raceways
optical fiber raceway, listed plenum
communications raceway, listed riser optical
fiber raceway, listed riser communications
raceway, listed general-purpose optical fiber
raceway, or listed general-purpose
communications raceway selected in
accordance with the provisions of 770.113,
800.110, and 800.113, and installed in
accordance with 362.24 through 362.56,
where the requirements applicable to
electrical nonmetallic tubing (ENT) apply.
(C) Cable Routing Assemblies. New
section.
770.113 Installation of Optical Fiber Cables
and Raceways, and Cables Routing
Assemblies. Installation of optical fiber
cables and raceways, and cable routing
assemblies shall comply with 770.113(A)
through (J). Installation of raceways shall also
comply with 770.12 and 770.110.
(A) Listing. Optical fiber cables and raceways,
and cable routing assemblies installed in
buildings shall be listed.
Exception: Optical fiber cables that comply
with 770.48 shall not be required to be listed.
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(C) Other Spaces Used For Environmental
Air (Plenums).
The following cables and raceways shall be
permitted in other spaces used for
environmental air as described in 300.22(C):
(1) Types OFNP and OFCP cables
(2) Plenum optical fiber raceway
(3) (2) Types OFNP and OFCP cables installed
in plenum optical fiber raceway or plenum
communications raceway
(4) (3) Types OFNP and OFCP cables
supported and plenum optical fiber raceways
supported by open metallic cable trays or
cable tray systems
(5) (4) Types OFNP, OFCP, OFNR, OFCR,
OFNG, OFCG,
OFN, and OFC cables installed in raceways
that are installed in compliance with
300.22(C)
(6)(5) Types OFNP, OFCP, OFNR, OFCR,
OFNG, OFCG, OFN, and OFC cables and
plenum optical fiber raceways, riser optical
fiber raceways and general-purpose optical
fiber raceways supported by solid bottom
metal cable trays with solid metal covers in
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other spaces used for environmental air
(plenums) as described in 300.22(C)
(D) Risers — Cables, Raceways and Cable
Routing Assemblies in Vertical Runs. The
following cables, raceways and cable routing
assemblies shall be permitted in vertical runs
penetrating one or more floors and in
vertical runs in a shaft:
(1) Types OFNP, OFCP, OFNR, and OFCR
cables
(2) Plenum and riser optical fiber raceways
(3) Riser cable routing assemblies
(4) (2) Types OFNP, OFCP, OFNR, and OFCR
cables installed in:
a. Plenum optical fiber raceway
b. Plenum communications raceway
c. Riser optical fiber raceway
d. Riser communications raceway
e. Riser cable routing assembly
(E) Risers — Cables and Raceways in Metal
Raceways.
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The following cables and raceways shall be
permitted in metal raceways in a riser having
firestops at each floor:
(1) Types OFNP, OFCP, OFNR, OFCR, OFNG,
OFCG, OFN, and OFC cables
(2) Plenum, riser, and general-purpose
optical fiber raceways
(3) (2) Types OFNP, OFCP, OFNR, OFCR,
OFNG, OFCG, OFN, and OFC cables installed
in:
a. Plenum optical fiber raceway
b. a. Plenum communications raceways
c. Riser optical fiber raceway
d. b. Riser communications raceways
e. General-purpose optical fiber raceway
f. c. General-purpose communications
raceway
(F) Risers — Cables, Raceways, and Cable
Routing Assemblies in Fireproof Shafts. The
following cables, raceways, and cable routing
assemblies shall be permitted to be installed
in fireproof riser shafts having firestops at
each floor:
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(1) Types OFNP, OFCP, OFNR, OFCR, OFNG,
OFCG, OFN, and OFC cables
(2) Plenum, riser, and general-purpose
optical fiber raceways
(3) Riser and general-purpose cable routing
assemblies
(4) (2) Types OFNP, OFCP, OFNR, OFCR,
OFNG, OFCG, OFN, and OFC cables installed
in:
a. Plenum optical fiber raceway
b. a. Plenum communications raceways
b. Plenum cable routing assemblies
c. Riser optical fiber raceway
d. c. Riser communications raceways
d. Riser cable routing assemblies
e. General-purpose optical fiber raceway
f. e. General-purpose communications
raceways
g. Riser cable routing assembly
h. f. General-purpose cable routing
assemblies assembly
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(G) Risers — One- and Two-Family
Dwellings. The following cables, raceways,
and cable routing assemblies shall be
permitted in one- and two-family dwellings:
(1) Types OFNP, OFCP, OFNR, OFCR, OFNG,
OFCG, OFN, and OFC cables
(2) Plenum, riser, and general-purpose
optical fiber raceways
(3) Riser and general-purpose cable routing
assemblies
(4) (2) Types OFNP, OFCP, OFNR, OFCR,
OFNG, OFCG, OFN, and OFC cables installed
in:
a. Plenum optical fiber raceway
b. a. Plenum communications raceways
b. Plenum cable routing assemblies
c. Riser optical fiber raceway
d. c. Riser communications raceways
d. Riser cable routing assemblies
e. General-purpose optical fiber raceway
f. e. General-purpose communications
raceways
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g. Riser cable routing assembly
h. f. General-purpose cable routing
assemblies assembly
(H) Cable Trays. The following cables and
raceways shall be permitted to be supported
by cable trays:
(1) Types OFNP, OFCP, OFNR, OFCR, OFNG,
OFCG, OFN, and OFC cables
(2) Plenum, riser, and general-purpose
optical fiber raceways
(3) (2) Types OFNP, OFCP, OFNR, OFCR,
OFNG, OFCG,
OFN, and OFC cables installed in:
a. Plenum optical fiber raceway
b. a. Plenum communications raceways
c. Riser optical fiber raceway
d. b. Riser communications raceways
e. General-purpose optical fiber raceway
f. c. General-purpose communications
raceways
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(I) Distributing Frames and Cross-Connect
Arrays. The following cables, raceways, and
cable routing assemblies shall be permitted
to be installed in distributing frames and
cross-connect arrays:
(1) Types OFNP, OFCP, OFNR, OFCR, OFNG,
OFCG, OFN, and OFC cables
(2) Plenum, riser, and general-purpose
optical fiber raceways
(3) Riser or general-purpose cable routing
assemblies
(4) (2) Types OFNP, OFCP, OFNR, OFCR,
OFNG, OFCG, OFN, and OFC cables installed
in:
a. Plenum optical fiber raceway
b. a. Plenum communications raceways
b. Plenum cable routing assemblies
c. Riser optical fiber raceway
d. c. Riser communications raceways
d. Riser cable routing assemblies
e. General-purpose optical fiber raceway
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f. e. General-purpose communications
raceways
g. Riser cable routing assembly
h. f. General-purpose cable routing
assemblies assembly
(J) Other Building Locations. The following
cables, raceways, and cable routing
assemblies shall be permitted to be installed
in building locations other than the locations
covered in 770.113(B) through (I):
(1) Types OFNP, OFCP, OFNR, OFCR, OFNG,
OFCG, OFN, and OFC cables
(2) Plenum, riser, and general-purpose
optical fiber raceways
(3) Riser and general-purpose cable routing
assemblies
(4) (2) Types OFNP, OFCP, OFNR, OFCR,
OFNG, OFCG, OFN, and OFC cables installed
in:
a. Plenum optical fiber raceway
b. a. Plenum communications raceways
b. Plenum cable routing assemblies
c. Riser optical fiber raceway
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d. c. Riser communications raceways
e. General-purpose optical fiber raceway
f. General-purpose communications raceway
g. d. Riser cable routing assemblies assembly
e. General-purpose communications
raceways
h. f. General-purpose cable routing
assemblies assembly
(3) Types OFNP, OFCP, OFNR, OFCR, OFNG,
OFCG, OFN, and OFC cables installed in a
raceway of a type recognized in Chapter 3
770.133 Installation of Optical fibers and
Electrical Conductors.
(A) With Conductors for Electric Light,
Power, Class 1,
Non–Power-Limited Fire Alarm, or Medium
Power
Network-Powered Broadband
Communications Circuits.
When optical fibers are within the same
composite cable for electric light, power,
Class 1, non–power-limited fire alarm, or
medium-power network-powered
770.133 Installation of Optical fibers and
Electrical Conductors.
(C) (B) With Other Circuits. Optical fibers shall be
permitted in the same cable, and conductive and
nonconductive optical fiber cables shall be
permitted in the same raceway, cable tray, box,
enclosure, or cable routing assembly, with
conductors of any of the following:
(1) Class 2 and Class 3 remote-control, signaling,
and power limited circuits in compliance with
Article 645 or Parts I and III of Article 725
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broadband communications circuits
operating at 600 1000 volts or less, they shall
be permitted to be installed only where the
functions of the optical fibers and the
electrical conductors are associated.
Nonconductive optical fiber cables shall be
permitted to occupy the same cable tray or
raceway with conductors for electric light,
power, Class 1, non–power-limited fire
alarm, Type ITC, or medium-power network-
powered broadband communications
circuits, operating at 600 1000 volts or less.
Conductive optical fiber cables shall not be
permitted to occupy the same cable tray or
raceway with conductors for electric light,
power, Class 1, non–power-limited fire
alarm, Type ITC, or medium-power network-
powered broadband communications
circuits.
Optical fibers in composite optical fiber
cables containing only current-carrying
conductors for electric light, power, Class 1
circuits rated 600 1000 volts or less shall be
permitted to occupy the same cabinet, cable
tray, outlet box, panel, raceway, or other
termination enclosure with conductors for
electric light, power, or Class 1 circuits
operating at 600 1000 volts or less.
Nonconductive optical fiber cables shall not
be permitted to occupy the same cabinet,
(2) Power-limited fire alarm systems in
compliance with Parts I and III of Article 760
(3) Communications circuits in compliance with
Parts I and V of Article 800
(4) Community antenna television and radio
distribution systems in compliance with Parts I
and V of Article 820.
(5) Low-power network-powered broadband
communications circuits in compliance with Parts
I and V of Article 830.
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outlet box, panel, or similar enclosure
housing the electrical terminations of an
electric light, power, Class 1, non–power-
limited fire alarm, or medium-power
network-powered broadband
communications circuit.
Exception No. 1: Occupancy of the same
cabinet, outlet box, panel, or similar
enclosure shall be permitted where
nonconductive optical fiber cable is
functionally associated with the electric light,
power, Class 1, non–power-limited fire
alarm, or medium-power network-powered
broadband communications circuit.
Exception No. 2: Occupancy of the same
cabinet, outlet box, panel, or similar
enclosure shall be permitted where
nonconductive optical fiber cables are
installed in factory or field-assembled control
centers.
Exception No. 3: In industrial establishments
only, where conditions of maintenance and
supervision ensure that only qualified
persons service the installation,
nonconductive optical fiber cables shall be
permitted with circuits exceeding 600 1000
volts.
Exception No. 4: In industrial establishments
only, where
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conditions of maintenance and supervision
ensure that only qualified persons service the
installation, optical fibers in composite
optical fiber cables containing current-
carrying conductors operating over 600 1000
volts shall be permitted to be installed.
Exception No. 5: Where all of the conductors
of electric light, power, Class 1, nonpower-
limited fire alarm, and medium-power
network-powered broadband
communications circuits are separated from
all of the optical fiber cables by a permanent
barrier or listed divider.
(B) With Communications Cables. Optical
fibers shall be permitted in the same cable,
and conductive and nonconductive optical
fiber cables shall be permitted in the same
raceway, cable tray, box, enclosure, raceway,
or cable routing assembly, with conductors
of any of the following:
(1) Communications circuits in compliance
with Parts I and IV V of Article 800
(2) Community antenna television and radio
distribution systems in compliance with Parts
I and IV V of Article 820
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(3) Low-power network-powered broadband
communications circuits in compliance with
Parts I and IV V of Article 830
(C) With Other Circuits. Optical fibers shall
be permitted in the same cable, and
conductive and nonconductive optical fiber
cables shall be permitted in the same
raceway, cable tray, box, enclosure, or cable
routing assembly, raceway, with conductors
of any of the following:
(1) Class 2 and Class 3 remote-control,
signaling, and power limited circuits in
compliance with Article 645 or Parts I and III
of Article 725
(2) Power-limited fire alarm systems in
compliance with Parts I and III of Article 760
Table 770.154(a) Applications of Listed
Optical Fiber Cables and Raceways, and
Cable Routing Assemblies in Buildings.
Revised.
770.179 Optical Fiber Cables.
(E) Circuit Integrity (CI) Cables. New section.
Field-Assembled Optical Fiber Cables. New
section.
770.179 Optical Fiber Cables. Add-
Temperature rating shall be marked on the jacket
of optical fiber cables that have a temperature
rating exceeding 600C (1400F).
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770.180 Grounding Devices. New section.
Chapter 8 Communication Systems
ARCTICLE 800 Communication Circuits ARCTICLE 800 Communication Circuits
800.2 Definitions.
Electrical Circuit Protection System. New
definition.
Innerduct. New definition.
800.3 Other Articles.
(D) Installation and Use. New subsection.
800.3 Other Articles.
(H) Temperature Limitation of Conductors. New
subsection.
800.12 Innerduct. New section.
800.24 Mechanical Execution of Work.
Communications circuits and equipment
shall be installed in a neat and workmanlike
manner. Cables installed exposed on the
surface of ceilings and sidewalls shall be
supported by the building structure in such a
manner that the cable will not be damaged
by normal building use. Such cables shall be
secured by hardware, including straps,
staples, cable ties, hangers, or similar fittings
designed and installed so as not to damage
the cable. The installation shall also conform
to 300.4(D) and 300.11. Nonmetallic cable
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ties and other nonmetallic cable accessories
used to secure and support cables in other
spaces used for environmental air (plenum)
shall be listed as having low smoke and heat
release properties.
800.48 Unlisted Cables Entering Buildings. Add-
The point of entrance shall be permitted to be
extended from the penetration of the external
wall or floor slab by continuously enclosing the
entrance cables in rigid metal conduit(RMC) or
intermediate metal conduit (IMC) to the point of
emergence.
800.49 Metallic Entrance Conduit
Grounding. New section.
800.110 Raceways and Cable Routing
Assemblies for Communications Wires and
Cables.
(A) Types of Raceways. Communications
wires and cables shall be permitted to be
installed in any raceway that complies with
either (A)(1) or (A)(2) and in cable routing
assemblies installed in compliance with
800.110(C).
(C) Cable Routing Assemblies. New section.
800.113 Installation of Communications
Wires, Cables and Raceways, and Cable
Routing Assemblies. Installation of
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communications wires, cables, and
raceways, and cable routing assemblies shall
comply with 800.113(A) through (L).
Installation of raceways and cable routing
assemblies shall also comply with 800.110.
(A) Listing. Communications wires,
communication cables, and communication
raceways, and cable routing assemblies
installed in buildings shall be listed.
Exception: Communications cables that
comply with 800.48 shall not be required to
be listed.
(C) Other Spaces Used for Environmental Air
(Plenums).
The following wires, cables, and raceways
shall be permitted in other spaces used for
environmental air as described in 300.22(C):
(1) Type CMP cables
(2) Plenum communications raceways
(3) Type CMP cables installed in plenum
communications raceways
(4) Type CMP cables and plenum
communications raceways supported by
open metallic cable trays or cable tray
systems
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(5) Types CMP, CMR, CMG, CM, and CMX
cables and communications wires installed in
raceways that are installed in compliance
with 300.22(C)
(6) Types CMP, CMR, CMG, CM, and CMX
cables, and plenum communications
raceways, riser communications
raceways and general-purpose
communications raceways supported by
solid bottom metal cable trays with solid
metal covers in other spaces used for
environmental air (plenums) as described in
300.22(C)
(7) Types CMP, CMR, CMG, CM, and CMX
cables installed in plenum communication
raceways, riser communication raceways,
and general-purpose communication
raceways supported by solid bottom metal
cable trays with solid metal covers in other
spaces used for environmental air (plenums)
as described in 300.22(C)
(D) Risers — Cables and Raceways in
Vertical Runs. The following cables, and
raceways, and cable routing assemblies shall
be permitted in vertical runs penetrating one
or more floors and in vertical runs in a shaft:
(1) Types CMP and CMR cables
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(2) Plenum and riser communications
raceways
(3) Plenum and riser cable routing
assemblies
(3) (4) Types CMP and CMR cables installed
in:
a. Plenum communications raceways
b. Riser communications raceways
c. Plenum and riser cable routing assembly
assemblies
d. Riser cable routing assemblies
(E) Risers — Cables and Raceways in Metal
Raceways.
The following cables, and raceways shall be
permitted in metal raceways in a riser having
firestops at each floor:
(1) Types CMP, CMR, CMG, CM, and CMX
cables
(2) Plenum, riser, and general-purpose
communications raceways
(3) Types CMP, CMR, CMG, CM, and CMX
cables installed
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in:
a. Plenum communications raceways
b. Riser communications raceways
c. General-purpose communications
raceways
(F) Risers — Cables, and Raceways, and
Cable Routing Assemblies in Fireproof
Shafts.
The following cables, and raceways, and
cable routing assemblies shall be permitted
to be installed in fireproof riser shafts having
firestops at each floor:
(1) Types CMP, CMR, CMG, CM, and CMX
cables
(2) Plenum, riser, and general-purpose
communications Raceways
(3) Plenum, riser, and general-purpose cable
routing assemblies.
(3) Types CMP, CMR, CMG, and CM cables
installed in:
a. Plenum communications raceways
b. Riser communications raceways
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c. General-purpose communications
raceways
d. Plenum cable routing assemblies
d. e. Riser cable routing assembly assemblies
e. f. General-purpose cable routing assembly
(G) Risers — One- and Two-Family
Dwellings. The following Cables, and
raceways, and cable routing assemblies shall
be permitted in one- and two-family
dwellings:
(1) Types CMP, CMR, CMG, and CM cables
(2) Type CMX cables less than 6 mm (0.25 in.)
in diameter
(3) Plenum, riser, and general-purpose
communications Raceways
(4) Plenum, riser, and general-purpose cable
routing assemblies
(4) (5) Types CMP, CMR, CMG, and CM
cables installed in:
a. Plenum communications raceways
b. Riser communications raceways
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c. General-purpose communications
raceways
d. Plenum cable routing assemblies
d. e. Riser cable routing assembly assemblies
e. f. General-purpose cable routing assembly
assemblies
(H) Cable Trays. The following wires, cables,
and raceways shall be permitted to be
supported by cable trays:
(1) Types CMP, CMR, CMG, and CM cables
(2) Plenum, riser, and general-purpose
communications raceways
(3) Communications wires and Types CMP,
CMR, CMG,
and CM cables installed in:
a. Plenum communications raceways
b. Riser communications raceways
c. General-purpose communications
raceways
(I) Distributing Frames and Cross-Connect
Arrays. The following wires, cables, and
raceways, cable routing assemblies shall be
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permitted to be installed in distributing
frames and cross-connect arrays:
(1) Types CMP, CMR, CMG, and CM cables
and communications wires
(2) Plenum, riser, and general-purpose
communications
Raceways
(3) Plenum, riser, and general-purpose cable
routing assemblies
(3) (4) Communications wires and Types
CMP, CMR, CMG, and CM cables installed in:
a. Plenum communications raceways
b. Riser communications raceways
c. General-purpose communications
raceways
d. Plenum cable routing assemblies
d. e. Riser cable routing assembly assemblies
e. f. General-purpose cable routing assembly
assemblies
(J) Other Building Locations. The following
wires, cables, and raceways, cable routing
assemblies shall be permitted to be installed
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in building locations other than the locations
covered in 800.113(B) through (I):
(1) Types CMP, CMR, CMG, and CM cables
(2) A maximum of 3 m (10 ft) of exposed
Type CMX in nonconcealed spaces
(3) Plenum, riser, and general-purpose
communications Raceways
(4) Plenum, riser, and general-purpose cable
routing assemblies
(4) (5) Communications wires and Types
CMP, CMR, CMG, and CM cables installed in:
a. Plenum communications raceways
b. Riser communications raceways
c. General-purpose communications
raceways
(5) (6) Types CMP, CMR, CMG, and CM
cables installed in:
a. Plenum cable routing assemblies
b. Riser cable routing assembly assemblies
b. c. General-purpose cable routing assembly
assemblies
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(6) (7) Communications wires and Types
CMP, CMR, CMG, CM, and CMX cables
installed in a raceways recognized of a type
recognized in Chapter 3
(7) (8) Type CMUC under-carpet
communications wires and cables installed
under carpet
(K) Multifamily Dwellings. The following
cables, raceways, and wiring cable routing
assemblies shall be permitted to be installed
in multifamily dwellings in locations other
than the locations covered in 800.113(B)
through (G):
(1) Types CMP, CMR, CMG, and CM cables
(2) Type CMX cables less than 6 mm (0.25 in.)
in diameter in nonconcealed spaces
(3) Plenum, riser, and general-purpose
communications Raceways
(4) Plenum, riser, and general-purpose cable
routing assemblies
(4) (5) Communications wires and Types
CMP, CMR, CMG, and CM cables installed in:
a. Plenum communications raceways
b. Riser communications raceways
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c. General-purpose communications
raceways
(5) (6) Types CMP, CMR, CMG, and CM
cables installed in:
a. Plenum cable routing assemblies
b. Riser cable routing assembly assemblies
b. c. General-purpose cable routing assembly
assemblies
(6) (7) Communications wires and Types
CMP, CMR, CMG, CM, and CMX cables
installed in a raceways recognized of a type
recognized in Chapter 3
(7) (8) Type CMUC under-carpet
communications wires and cables installed
under carpet
(L) One- and Two-Family Dwellings. The
following cables, and raceways, and cable
routing assemblies shall be permitted to be
installed in one- and two-family dwellings in
locations other than the locations covered in
800.113(B) through (F):
(1) Types CMP, CMR, CMG, and CM cables
(2) Type CMX cables less than 6 mm (0.25 in.)
in diameter
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(3) Plenum, riser, and general-purpose
communications Raceways
(4) Plenum, riser, and general-purpose cable
routing assemblies
(4) (5) Communications wires and Types
CMP, CMR, CMG, and CM cables installed in:
a. Plenum communications raceways
b. Riser communications raceways
c. General-purpose communications
raceways
(5) (6) Types CMP, CMR, CMG, and CM
cables installed in:
a. Plenum cable routing assemblies
b. Riser cable routing assembly assemblies
b. c. General-purpose cable routing assembly
assemblies
(6) (7) Communication wires and Types CMP,
CMR, CMG, CM, and CMX cables installed in
a raceway of a type recognized in Chapter 3
(7) Type CMUC under carpet
communications wires and
cables installed under carpet
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(8) Hybrid power and communications cable
listed in accordance with 800.179(I)
800.133 Installation of Communications Wires,
Cables, and Equipment.
(A) Separation from Other Conductors.
(1) In Raceways, Cable Trays, Boxes, Cables, and
Enclosures.
(b) (a) Other Circuits. Communications cables shall
be permitted in the same raceway, cable tray, or
enclosure with cables of any of the following:
(1) Class 2 and Class 3 remote-control, signaling,
and
power-limited circuits in compliance with Parts I
and
III of Article 725
(2) Power-limited fire alarm systems in
compliance with
Parts I and III of Article 760
(3) Nonconductive and conductive optical
fiber cables in compliance with Parts I and
V or Article 770.
(4) Community antenna television and radio
distribution systems in compliance with
Parts I and V of Article 820.
(5) Low-power network-powered broadband
communications circuits in compliance
with Parts I and V of Article 830.
800.154 Applications of Listed
Communications Wires,
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Cables, and Raceways, Listed Cable Routing
Assembly. Permitted and nonpermitted
applications of listed communications wires,
cables, and raceways, and listed cable
routing assemblies shall be in accordance
with one of the following:
(1) Listed communications wires and
cables as indicated in Table
800.154(a).
(2) Listed communication raceways as
indicated in Table 800.154(b).
(3) Listed cable routing assemblies as
indicated in Table 800.154(c).
as indicated in Table 800.154(a). The
permitted applications shall be subject to the
installation requirements of 800.110 and
800.113. The substitutions for
communications cables listed in Table
800.154(b) (d) and illustrated in Figure
800.154 shall be permitted.
Table 800.154(a) Applications of Listed
Communication Wires and Cables in
Buildings. Revised.
Table 800.154(b) Applications of Listed
Communication Raceways in Buildings. New
table.
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Table 800.154(c) Applications of Listed
Cable Routing Assemblies in Buildings. New
table.
800.170 Equipment.
(C) Plenum Grade Cable Ties. New section.
800.179 Communications Wires and Cables.
(G) Circuit Integrity (CI) Cable or Electrical
Circuit Protective System. New section and
subsections.
800.179 Communications Wires and Cables. Add-
The temperature rating shall be marked on the
jacket of communications cables that have a
temperature rating exceeding 600C (1400F).
800.180 Grounding Devices. New section.
800.182 Communications Raceways and
Cable Routing
Assemblies. Communications raceways and
cable routing assemblies shall be listed in
accordance with 800.182(A) through (C).
(A) Plenum Communications Raceways and
Plenum Cable Routing Assemblies. Plenum
communications Raceways and plenum cable
routing assemblies shall be listed as plenum
optical fiber raceways shall be permitted for
use in ducts, plenums, and other spaces used
for environmental air and shall also be listed
as having adequate fire-resistant and low
smoke-producing characteristics.
800.182 Communications Raceways and Cable
Routing
Assemblies. Cable routing assemblies and
communications raceways Communications
raceways and cable routing assemblies shall be
listed in accordance with 800.182(A) through (C)
Cable routing assemblies shall be marked in
accordance with Table 800.182(a).
Communications raceways shall be marked in
accordance with Table 800.182(b).
(A) Plenum Cable Routing Assemblies and
Plenum Communications Raceways
Communications Raceways and Plenum Cable
Routing Assemblies. Plenum communications
raceways and Plenum cable routing assemblies
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(B) Riser Communications Raceways and
Riser Cable Routing Assemblies. Riser
communications raceways and riser cable
routing assemblies shall be listed as having
adequate fire-resistant characteristics
capable of preventing the carrying of fire
from floor to floor.
(C) General-Purpose Communications
Raceways and General-Purpose Cable
Routing Assemblies. General-purpose
communications raceways and general-
purpose cable routing assemblies shall be
listed as being resistant to the spread of fire.
and plenum communications raceways shall be
listed as having adequate fire-resistant and low
smoke-producing characteristics.
(B) Riser Communications Raceways and Riser
Cable Routing Assemblies and Riser
Communications Raceways. Riser cable Riser
communications raceways and riser cable routing
assemblies and riser communications raceways
shall be listed as having adequate fire-resistant
characteristics capable of preventing the carrying
of fire from floor to floor.
(C) General-Purpose Communications Raceways
and General-Purpose Cable Routing Assemblies
and General-Purpose Communications
Raceways. General-purpose cable routing
assemblies communications raceways and
general-purpose communications raceways cable
routing assemblies shall be listed as being
resistant to the spread of fire.
ARTICLE 810
Radio and Television Equipment
810.6 Antenna Lead-In Protectors. New
section.
810.7 Grounding Devices. New section.
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810.15 Grounding. Masts and metal structures
supporting antennas shall be grounded in
accordance with 810.21, unless the antenna and
its related supporting mast or structure are within
a zone of protection defined by a 46 m (150 ft)
radius rolling sphere.
ARTICLE 820 Community Antenna Television
and Radio Distribution Systems
820.3 Other Articles.
(B) Wiring is Ducts for Dust, Loose Stock, or
Vapor Removal. New section inserted.
(C) Equipment in Other Space Used for
Environmental Air. New section.
(H) Cable Routing Assemblies. The
definition in Article 100, 770.2, the
applications in Table 800.154©, 770.154 ,
and installation requirements rules in
800.110 770.113 shall apply to Article 820
and 800.113.
820.24 Mechanical Execution of Work.
Community television and radio distribution
systems shall be installed in a neat and
workmanlike manner. Coaxial cables
installed exposed on the surface of ceiling
and sidewalls shall be supported by the
building structure in such a manner that the
cables will not be damaged by normal
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building use. Such cables shall be secured by
hardware including straps, staples, cable ties,
hangers, or similar fittings designed and
installed so as not to damage the cable. The
installation shall also conform to 300.4(D)
and 300.11. Nonmetallic cable ties and other
nonmetallic cable accessories used to secure
and support cables in other spaces used for
environmental air (plenum) shall be listed as
having low smoke and heat release
properties.
820.47 Underground Coaxial Cables
Entering Buildings.
(A) Underground Systems with Electric
Light, and Power, Class 1, or Non-Power-
Limited Fire Alarm Circuits
Conductors. Underground coaxial cables in a
duct, pedestal, handhole enclosure, or
manhole that contains electric light, or
power, Class 1 or non-power-limited fire
alarm circuit conductors or Class 1 circuits
shall be in a section permanently separated
from such conductors by means of a suitable
barrier.
820.48 Unlisted Cables Entering Buildings. Add-
The point of entrance shall be permitted to be
extended from the penetration of the external
wall or floor slab by continuously enclosing the
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entrance cables in rigid metal conduit (RMC) or
intermediate metal conduit (IMC) to the point of
emergence.
820.49 Metallic Entrance Conduit
Grounding. New section.
820.100 Cable Bonding and Grounding. The
shield of the coaxial cable shall be bonded or
grounded as specified in 820.100(A) through
(D).
Exception: For communications systems
using coaxial
cable confined within the premises and
isolated from outside cable plant, the shield
shall be permitted to be grounded by a
connection to an equipment grounding
conductor as described in 250.118.
Connecting to an equipment grounding
conductor through a grounded receptacle
using a dedicated bonding jumper grounding
conductor and a permanently connected
listed device shall be permitted. Use of a cord
and plug for the connection to an equipment
grounding conductor shall not be permitted.
(A) Bonding Conductor or Grounding
Electrode Conductor.
(4) Length. The bonding conductor or
grounding electrode conductor shall be as
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short as practicable. In one- and two-family
dwellings, the bonding conductor or
grounding electrode conductor shall be as
short as practicable, not to exceed 6.0 m (20
ft) in length.
(B) Electrode. The bonding conductor or
grounding electrode conductor shall be
connected in accordance with 820.100(B)(1),
(B)(2), or (B)(3).
(2) In Buildings or Structures with
Grounding Means.
(3) The power service accessible means
external to enclosures as covered in 250.94,
Exception
(3) In Buildings or Structures Without an
Intersystem
Bonding Termination or Grounding Means.
If the building or structure served has no
intersystem bonding termination or
grounding means, as described in
820.100(B)(2), the grounding electrode
conductor shall be connected to either of the
following:
(1) To any one of the individual grounding
electrodes described in 250.52(A)(1), (A)(2),
(A)(3), or (A)(4)
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(2) If the building or structure served has no
intersystem bonding termination or
grounding means, as described in
820.100(B)(2) or (B)(3)(1), to any one of the
individual grounding electrodes described in
250.52(A)(5), (A)(7) and (A)(8). Steam or hot
water pipes or air terminal conductors
(lightning-rod conductors) shall not be
employed for bonding conductors or
grounding electrode conductors.
820.106 Grounding and Bonding at Mobile
Homes.
(A) Grounding. Grounding shall comply with
820.106(A)(1) and (A)(2).
(1) Where there is no mobile home service
equipment located within 9.0 m (30 ft) of the
exterior wall of the mobile home it serves,
the coaxial cable shield ground, or surge
arrester grounding arrestor ground, shall be
connected to a grounding electrode
conductor or grounding electrode in
accordance with 820.100(B)(3).
(2) Where there is no mobile home
disconnecting means grounded in
accordance with 250.32 and located within
9.0 m (30 ft) of the exterior wall of the
mobile home it serves, the coaxial cable
shield ground, or surge arrester grounding
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terminal ground, shall be connected to a
grounding electrode in accordance with
820.100(B)(3).
820.110 Raceways and Cable Routing
Assemblies for Coaxial Cables.
(A) Types of Raceways. Coaxial cables shall
be permitted to be installed in any raceway
that complies with either (A)(1) or (A)(2) and
in cable routing assemblies installed in
compliance with 820.110(C).
(2) Communication Other Permitted
Raceways. Coaxial cables shall be permitted
to be installed in listed plenum
communications raceway, listed riser
communications raceways, or and listed
general purpose communications raceways
selected in accordance with the provisions of
800.110, 800.113, and 820.113, and installed
in accordance with 362.24 through 362.56,
where the requirements applicable to
electrical nonmetallic tubing (ENT) apply.
(C) Cable Routing Assemblies. New section
and subsections.
820.110 Raceways and Cable Routing Assemblies
for Coaxial Cables.
(3) Innerduct for Coaxial Cables. New
subsections.
820.113 Installation of Coaxial Cables.
(C) Other Spaces Used For Environmental
Air (Plenums).
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The following cables shall be permitted in
other spaces used for environmental air as
described in 300.22(C):
(1) Type CATVP cable
(2) Type CATVP cable installed in plenum
communications raceways
(3) Type CATVP cable supported by open
metallic cable trays or cable tray systems
(4) Types CATVP, CATVR, CATV, and CATVX
cables installed in raceways that are installed
in compliance with 300.22(C)
(5) Types CATVP, CATVR, CATV, and CATVX
cables supported by solid bottom metal
cable trays with solid metal covers in other
spaces used for environmental air (plenums)
as described in 300.22(C) Informational
Note: For information on fire protection of
wiring installed in other spaces used for
environmental air see 4.3.11.2, 4.3.11.4, and
4.3.11.5 of NFPA 90A-2009, Standard for the
Installation of Air-Conditioning and
Ventilating Systems.
(6) Types CATVP, CATVP, CATV, and CATVX
cables installed in plenum communication
raceways, riser communication raceways, or
general-purpose communication raceways
supported by solid bottom metal cable trays
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with solid metal covers in other spaces used
for environmental air (plenums) as described
in 300.22(C)
(D) Risers — Cables in Vertical Runs. The
following cables shall be permitted in vertical
runs penetrating one or more floors and in
vertical runs in a shaft:
(1) Types CATVP and CATVR cables
(2) Types CATVP and CATVR cables installed
in:
a. Plenum communications raceways
b. Plenum cable routing assemblies
b. c. Riser communications raceways
c. d. Riser cable routing assembly assemblies
(E) Risers — Cables in Metal Raceways. The
following cables shall be permitted in metal
raceways in a riser having firestops at each
floor:
(1) Types CATVP, CATVR, CATV, and CATVX
cables
(2) Types CATVP, CATVR, CATV, and CATVX
cables installed in:
a. Plenum communications raceways
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b. Riser communications raceways
c. General-purpose communications
raceways
(F) Risers — Cables in Fireproof Shafts. The
following cables shall be permitted to be
installed in fireproof riser shafts with
firestops at each floor:
(1) Types CATVP, CATVR, CATV, and CATVX
cables
(2) Types CATVP, CATVR, and CATV cables
installed in:
a. Plenum communications raceways
b. Plenum cable routing assemblies
b. c. Riser communications raceways
c. General-purpose communications raceway
d. Riser cable routing assembly assemblies
e. General-purpose communications
raceways
e. (f) General-purpose cable routing
assembly assemblies
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(G) Risers — One- and Two-Family
Dwellings. The following cables shall be
permitted in one- and two-family dwellings:
(1) Types CATVP, CATVR, and CATV cables
(2) Type CATVX cable less than 10 mm (0.375
in.) in diameter
(3) Types CATVP, CATVR, and CATV cables
installed in:
a. Plenum communications raceways
b. Plenum cable routing assemblies
b. c. Riser communications raceways
c. General-purpose communications raceway
d. Riser cable routing assembly assemblies
e. General-purpose communications
raceways
e. f. General-purpose cable routing assembly
assemblies
(H) Cable Trays. The following cables shall be
permitted
to be supported by cable trays:
(1) Types CATVP, CATVR, and CATV cables
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(2) Types CATVP, CATVR, and CATV cables
installed in:
a. Plenum communications raceways
b. Riser communications raceways
c. General-purpose communications
raceways
(I) Distributing Frames and Cross-Connect
Arrays. The following cables shall be
permitted to be installed in distributing
frames and cross-connect arrays:
(1) Types CATVP, CATVR, and CATV cables
(2) Types CATVP, CATVR, and CATV cables
installed in:
a. Plenum communications raceways
b. Plenum cable routing assemblies
b. c. Riser communications raceways
d. Riser cable routing assembly assemblies
c. e. General-purpose communications
raceways
d. Riser cable routing assembly
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e. f. General-purpose cable routing assembly
assemblies
(J) Other Building Locations. The following
cables and cable routing assemblies shall be
permitted to be installed in building
locations other than the locations covered in
820.113(B) through (I):
(1) Types CATVP, CATVR, and CATV cables
(2) A maximum of 3 m (10 ft) of exposed
Type CATVX
cable in nonconcealed spaces
(3) Types CATVP, CATVR, and CATV cables
installed in:
a. Plenum communications raceways
b. Plenum cable routing assemblies
b. c. Riser communications raceways
d. Riser cable routing assembly assemblies
c. e. General-purpose communications
raceways
d. Riser cable routing assembly
e. f. General-purpose cable routing assembly
assemblies
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(4) Types CATVP, CATVR, CATV, and Type
CATVX cables installed in a raceway of a type
recognized in Chapter 3
(K) One- and Two-Family and Multifamily
Dwellings.
The following cables and cable routing
assemblies shall be permitted to be installed
in one- and two-family and multifamily
dwellings in locations other than those
locations covered in 820.113(B) through (I):
(1) Types CATVP, CATVR, and CATV cables
(2) Type CATVX cable less than 10 mm (0.375
in.) in
diameter
(3) Types CATVP, CATVR, and CATV cables
installed in:
a. Plenum communications raceways
b. Plenum cable routing assemblies
b. c. Riser communications raceways
d. Riser cable routing assembly assemblies
c. e. General-purpose communications
raceways
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d. Riser cable routing assembly
e. f. General-purpose cable routing assembly
assemblies
(4) Types CATVP, CATVR, CATV, and Type
CATVX cables installed in a raceway of a type
recognized in Chapter 3
820.179 Coaxial Cables. Add-
Coaxial cables shall have a temperature rating of
not less than 600C (1400F). The temperature
rating shall be marked on the jacket of coaxial
cables that have a temperature rating exceeding
600C (1400F).
820.180 Grounding Devices. New section.
ARTICLE 830 Network-Powered Broadband
Communication Systems
830.3 Other Articles
(B) Wiring in Ducts for Dust, Loose Stock, or
Vapor Removal. New subsection inserted.
(F) Protection against Physical Damage.
New subsection inserted.
830.24 Mechanical Execution of Work.
Network-powered broadband
communications circuits and equipment shall
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be installed in a neat and workmanlike
manner. Cables installed exposed on the
surface of ceilings and sidewalls shall be
supported by the building structure in such a
manner that the cable will not be damaged
by normal building use. Such cables shall be
secured by hardware including straps,
staples, cable ties, hangers, or similar fittings
designed and installed so as not to damage
the cable. The installation shall also conform
to 300.4(D) and 300.11. Nonmetallic cable
ties and other nonmetallic cable accessories
used to secure and support cables in other
spaces used for environmental air (plenums)
shall be listed as having low smoke and heat
release properties.
830.49 Metallic Entrance Conduit
Grounding. New section.
830.106 Grounding and Bonding at Mobile
Homes.
(A) Grounding. Grounding shall comply with
830.106(A)(1) or (A)(2).
(1) Where there is no mobile home service
equipment located within 9.0 m (30 ft) of the
exterior wall of the mobile home it serves,
the network-powered broadband
communications cable shield, network-
powered broadband communications cable
metallic members not used for
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communications or powering, network
interface unit, and primary protector ground
grounding terminal shall be installed
connected to a grounding electrode
conductor or grounding electrode in
accordance with 830.100(B)(3).
(2) Where there is no mobile home
disconnecting means grounded in
accordance with 250.32 and located within
sight from, and not more than 9.0 m (30 ft)
of, the exterior wall of the mobile home it
serves, the network-powered broadband
communications cable shield, network-
powered broadband communication cable
metallic members not used for
communication or powering, network
interface unit, and primary protector
grounding terminal ground shall be installed
connected to a grounding electrode in
accordance with 830.100(B)(3).
830.110 Raceways and Cable Routing
Assemblies for for Low- and Medium-Power
Network-Powered Broadband
Communications Cables.
(A) Types of Raceways. New section
inserted.
(1) Raceways Recognized in Chapter 3.
Renumbered.
830.110 Raceways and Cable Routing Assemblies
for Network-Powered Broadband
Communications Cables.
(A)(3) Innerduct for Low-Power Network-
Powered Broadband Communications Cables.
New section.
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(2) Communications Raceways. New section.
(C) Cable Routing Assemblies. New section
and subsections.
830.113 Installation of Network-Powered
Broadband Communication Cables.
(C) Other Spaces Used Fir Environmental Air
(Plenums)
(6) Types BLP, BMR, BLR, BM, BL, and BLX
cables installed in plenum communications
raceways, riser communication =s raceways,
or general-purpose communications
raceways supported by solid bottom metal
cables trays with solid mental covers in other
spaces used for environmental (plenums) as
described in 300.22(C)
(D) Risers- Cables in Vertical Runs.
(1) Types BLP, BMR, and BLR cables
(2) Types BLP and BLR cables installed in:
a. Plenum communications raceways
b. Plenum cable routing assemblies
b. c. Riser communications raceways
c. d. Riser cable routing assembly assemblies
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(E) Risers — Cables in Metal Raceways. The
following cables shall be permitted in a metal
raceway in a riser with firestops at each
floor:
(1) Types BLP, BMR, BLR, BM, BL, and BLX
cables
(2) Types BLP, BLR, and BL cables installed in:
a. Plenum communications raceways
b. Riser communications raceways
c. General-purpose communications
raceways
(F) Risers — Cables in Fireproof Shafts. The
following cables shall be permitted to be
installed in fireproof riser shafts with
firestops at each floor:
(1) Types BLP, BMR, BLR, BM, BL, and BLX
cables
(2) Types BLP, BLR, and BL cables installed in:
a. Plenum communications raceways
b. Plenum cable routing assemblies
b. c. Riser communications raceways
d. Riser cable routing assembly assemblies
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c. e. General-purpose communications
raceways
d. Riser cable routing assembly
e. f. General-purpose cable routing assembly
assemblies
(G) Risers — One- and Two-Family
Dwellings. The following cables shall be
permitted in one- and two-family dwellings:
(1) Types BLP, BMR, BLR, BM, and BL cables
and Types BL and BLX cables less than 10 mm
(0.375 in.) in diameter
(2) Types BLP, BLR, and BL cables installed in:
a. Plenum communications raceways
b. Plenum cable routing assemblies
b. c. Riser communications raceways
d. Riser cable routing assembly assemblies
c. e. General-purpose communications
raceways
d. Riser cable routing assembly
e. f. General-purpose cable routing assembly
assemblies
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(H) Other Building Locations. The following
cables and raceways shall be permitted to be
installed in building locations other than
those covered in 830.113(B) through (G):
(1) Types BLP, BMR, BLR, BM, and BL cables
(2) Types BLP, BMR, BLR, BM, BL, and BLX
cables
installed in a raceway
(3) Types BLP, BLR, and BL cables
a. Plenum communications raceways
b. Plenum cable routing assemblies
b. c. Riser communications raceways
d. Riser cable routing assembly assemblies
c. e. General-purpose communications
raceways
d. Riser cable routing assembly
e. f. General-purpose cable routing assembly
assemblies
(4) Types BLX and BL cables less than 10 mm
(0.375 in.) in diameter in one- and two-
family dwellings
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(5) Types BMU and BLU cables entering the
building from outside and run in rigid metal
conduit (RMC) or intermediate metal conduit
(IMC) where the conduit is connected by a
bonding conductor or grounding electrode
conductor in accordance with 830.100(B)
(6) A maximum length of 15 m (50 ft), within
the building, of Type BLX cable entering the
building from outside and terminating at an
NIU or a primary protection location
830 180 Grounding Devices. New section.
ARTICLE 840 Premises-Powered Broadband
Communications Systems
ARTICLE 840 Premises-Powered Broadband
Communications Systems
840.3 Other Articles.
(B) Cables in Ducts for Dust, Loose Stock, or
Vapor Removal. New section.
(D) Installation and Use. New section.
840.45 Overhead (aerial) Communications Wires
and Cables. New section.
840.46 Overhead (aerial) Coaxial Cables. New
section.
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840.48 Unlisted Wires and Cables Entering
Buildings.
(A) Optical Fiber Cables. New subsection.
(B) Communications Wires and Cables. New
subsection.
(C) Coaxial Cables. New subsection.
840.49 Metallic Entrance Conduit
Grounding. New section.
804.93 Grounding or Interruption. Revised.
840.106 Grounding and Bonding at Mobile
Homes.
(A) Grounding. Grounding shall comply with
(1) and (2).
(1) Where there is no mobile home service
equipment located within 9.0 m (30 ft) of the
exterior wall of the mobile home it serves,
the non-current-carrying metallic members
of optical fiber cables shall be connected to a
grounding electrode in accordance with
770.106(A)(1). The ONT, if required to be
grounded, shall be connected to a grounding
electrode in accordance with 800.106(A)(1)
840.100. Premises communications circuits
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and premises CATV circuits shall be
grounded in accordance with 820.106(A)(1)
840.93, unless the ONT is listed to provide
the grounding path for the shield of the
coaxial cable. The grounding electrode shall
be bonded in accordance with 770.106(B).
(2) Where there is no mobile home
disconnecting means grounded in
accordance with 250.32 and located within
9.0 m (30 ft) of the exterior wall of the
mobile home it serves, the non-current-
carrying metallic members of optical fiber
cables shall be connected to a grounding
electrode in accordance with 700.106(A)(2).
The ONT, if required to be grounded, shall be
connected to a grounding electrode in
accordance with 820.106(A)(2), unless the
ONT is listed to provide the grounding path
for the shield of the coaxial cable. The
grounding electrode shall be bonded in
accordance with 770.106(B) 800.100(B)(3).
Premises communications circuits and
premises CATV circuits shall be grounded in
accordance with 840.93.
Part VI. Premises Powering of Communications
Equipment over Communications Cables. New
part and section.
840.170 Equipment and Cables.
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(D) Cable Routing Assemblies and
Communications Raceways. New section.
(E) Premises Communications Wires and Cables.
New section.
840.180 Grounding Devices. New section.
Chapter 9 Tables
Notes to Tables
(6) For combinations of conductors of
different sizes, use actual dimensions or
Table 5 and Table 5A for dimensions of
conductors and Table 4 for the applicable
conduit or tubing dimensions.
(7) When calculating the maximum number
of conductors or cables permitted in a
conduit or tubing, all of the same size (total
cross-sectional area including insulation), the
next higher whole number shall be used to
determine the maximum number of
conductors permitted when the calculation
results in a decimal greater than or equal to
of 0.8 or larger. When calculating the size for
conduit or tubing permitted for a single
conductor, one conductor shall be permitted
when the calculation results in a decimal
greater than or equal to 0.8.
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(9) A multiconductor cable, optical fiber
cable, or flexible cord of two or more
conductors shall be treated as a single
conductor for calculating percentage conduit
fill area. For cables that have elliptical cross
sections, the cross-sectional area calculation
shall be based on using the major diameter
of the ellipse as a circle diameter.
(10) The values for approximate conductor
diameter and area shown in Table 5 are
based on worst-case scenario and indicate
round concentric-lay-stranded conductors.
Solid and round concentric-lay-stranded
conductor values are grouped together for
the purpose of Table 5. Round compact-
strand conductor values of the conductor
diameter and area are known, they shall be
permitted to be used.
Article 362- Electrical Nonmetallic Tubing
(ENT). Revised.
Table 5 Dimensions of Insulated Conductors
and Fixture Wire. Revised.
Table C-4 Maximum Number of Conductors
or Fixture Wires in Intermediate Metal
Conduit. Revised.
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Table C-6 Maximum Number of Conductors
or Fixture Wires in Liquidtight Flexible
Nonmetallic Conduit. Revised.
Table C-7 Maximum Number of Conductors
or Fixture Wires in Liquidtight Flexible
Metal Conduit. Revised.
Table C-8 Maximum Number of Conductors
or Fixture Wires in Rigid Metal Conduit.
Revised.
Table C-9 Maximum Number of Conductors
or Fixture Wires in Rigid PVC Conduit.
Revised.
Table C-10 Maximum Number of
Conductors or Fixture Wires in Rigid PVC
Conduit. Revised.
Table C-11 Maximum Number of
Conductors or Fixture Wires in Type A, Rigid
OVC Conduit. Rigid.
Informative Annex J ADA Standards for
Accessible Design. New Annex.