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GENERAL ELECTRICAL PROTECTION AND GROUNDING REQUIREMENTS
Electrical Hazards
Lightning an electrical discharge which occurs between clouds and also
from cloud to earth.
Power contact / induction
Acoustic Shock results from abnormally high sound level, the physicaleffects of which may vary from minor discomfort to serious injury.
Electric Shock current through the body rather than voltage of the circuit
determines electric shock intensity. Voltage is significant only in so far as
it is one of the factors determining the magnitude of current.
The average resistance of a dry adult human body is approximately
1000 ohms. Wet or damaged skin reduces this figure and 1500
ohms is a conservative figure representing the body resistance for
safety calculations.
Ventricular fibrillation is likely to occur when a 60Hz rms current of
0.030 amperes and above passes through ones chest cavity.
Because of this, any circuit from which in excess of 30ma rms AC or
90ma DC can be drawn through a 1500 ohm resistor (45V RMS ACOR 135VDC) shall be classified as hazardous.
The potential difference at any time between any exposed structure
(Equipment cabinets, Housings, Supports, etc.) to ground (Floor,
Earth, etc.) or between any exposed structure within the reach of an
adult person (Approx. 1.5 meters) shall be no greater than 45 volts
rms AC or 135 volts DC.
The potential difference at any time between two points on the floor
or earth surface separated by a distance of one pace, or about one
meter, in the direction of maximum potential gradient shall be no
greater than 45 volts rms AC or 135 volts DC.
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Protection Methods
Shielding it is the provision of a grounded electrical conducting material
located such that foreign potential will be intercepted and surge currents
diverted to ground with the least damage to plant equipment possible.
Voltage Limiting prevents development of hazardous potential
difference in communication plant by direct bonding, when permissible or
by use of surge arresters, discharge gaps, diodes, etc. which operate
under abnormal voltage condition.
Current Limiting and Interrupting current in a circuit can be kept from
rising above a predetermined value by the use of a fuse in series with acircuit. When current flows through a fuse for a specified time with a
magnitude greater than its rating, the fuse will interrupt the current.
Grounding and Bonding used to divert undesired currents before they
reach the equipment being protected and often are installed both at and
some distance away from the protected equipment.
Ground Resistance it is the resistance path of a ground connection
which includes the ground wire and its connection to ground
electrode. The ground electrode, the contact between the electrode
and the earth and the surrounding soil. This value should NEVER
EXCEED 5.0 OHMS FOR EQUIPMENT LOCATIONS, ANTENNA
TOWERS, AND ALL ALLIED INSTALLATIONS, AND 25 OHMS
FOR OUTSIDE PLANT TELEPHONE POLES AND MANHOLESAS WELL AS CUSTOMER PREMISES.
Made Ground it is an electrode buried in the ground for the purpose
of establishing a low resistance electrical contact with the earth.
Example: driven rods, driven pipes, buried plates, buried cones, or
other similar devices placed in the ground.
Methods and Materials
Lightning Rods is a metal strip or rod, usually of copper or similar
conductive material, designed to protect tall or isolated structures (such
as the roof of a building or the mast of a vessel) from lightning damage.
Fuses and Current Interrupting - a device used in electrical systems to
protect against excessive current.
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Surge Arresters these are normally open circuited devices and pass no
significant current at normal operating potentials.
Grounding and Bonding - provides certain level of safety to humans and
property in case of equipment damages.
Measurements
Ground Resistance Test Methods measurement procedures that is simple
and straight forward and the instruments are mostly direct reading.
Methods for Ground Resistance Measurements
Direct Method or two terminal test the simplest way to make anearth resistance test.
The fall of potential method or three terminal test
Voltmeter-Ammeter Method
Triangulation Method
Earth Resistivity it is the resistance of parallel faces of a one cubic
centimeter of soil. Expressed in ohm-centimeter.
Determining Good Electrode Location
Drive rods in various locations to such depths as may be required
and measure the resistances while the rods are being driven.
Measure the earth resistivity before driving ground rods then
calculate the number and length of rods required.
How to Improve Grounds
Lengthen the ground-electrode in the earth.
Use multiple rods.
Treat the soil when 1 & 2 are not feasible.
Maintenance and Inspection
Grounding system requirements from year to year can change
depending on the following factors:
A plant or facility can expand in size or change its operation and
such changes create different needs in the grounding system.
As more non-metallic pipes and conduits are installed underground,
such installation becomes less and less dependable as effective low-
resistance ground connections.
In many locations, the water table is gradually falling, and grounds
formerly effective may end up uneffective.
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Ground resistance shall be tested when installed and periodically
afterwards, at least once a year during the dry or non-rainy months and
ALL VALUES OBTAINED SHALL BE NO GREATER THAN THE RULE
REQUIRED. (See protection method).
All ground connections, be it solderless or soldered, shall be checked at
least once a year to be sure they are tight. Physical damage to ground
wires shall be checked at the same time and damages rectified or
damaged conductors replaced.
Do not test grounds during thunderstorm days.
Never take hold of two wires or a wire or rod or probe in such a way that
you complete a circuit through yourself.
Stray earth currents, accidental contacts or ground faults in the power
system may produce an undeterminable difference of potential between
two points, so use rubber gloves and handle ground wires under test as
if they are energized.
GENERAL STRENGTH REQUIREMENTS
Loading ZonesHeavy Loading Zone this loading shall be taken as the resultant stress
due to wind and dead weight for 240 kph wind velocity.
Medium Loading Zone - this loading shall be taken as the resultant stress
due to wind and dead weight for 200 kph wind velocity.
Light Loading Zone - this loading shall be taken as the resultant stress due
to wind and dead weight for 160 kph wind velocity.
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POWER SOURCES
Storage Batteries and Chargers
Batteries should be located where temperatures range between 15.5 and
32.2 degrees Celsius (60 degrees and 90 degrees Fahrenheit). Higher
temperature will shorten battery life and lower temperature will decrease
the ampere-hour capacity and may damage the battery by freezing
especially when the batteries are in low state of charge.
Lead acid or similar gas emitting battery installations where the
aggregate power (ampere-hour rating, at the 8-hour rate to 1.75 volts percell multiplied by the battery voltage) exceeds 5 kilowatts shall be located
in a properly ventilated room separated from the equipment room or
location where people are staying.
Explosion resistant vents shall be provided for all lead acid or similar gas
emitting batteries above 10 ampere-hour capacity and ascertained by
periodic inspection that the vents are free from obstruction.
Ventilation of the battery room is very important especially during high
charging and discharging condition. Although the battery is fitted with an
explosion proof vent, an enclosed room could develop a sufficiently high
concentration of an explosive gaseous mixture which could be ignited by
sparks from adjacent electrical or electronic equipment as well as
accidental sparks or open flame introduced by personnel. All air moved
by ventilation in the battery room or area should be exhausted into theoutside atmosphere and should not be allowed to recirculate into other
confined areas.
Smoking and storing of inflammable materials is prohibited in battery
rooms and NO SMOKING signs should be posted in conspicuous
locations inside and before entering battery rooms.
Batteries, where the corrosive electrolyte maybe added in the field or
customer location, transported by air or boat shall be shipped dry
charged. They may be transported with electrolyte via land
transportation provided electrolyte leakage or spillage are contained with
its crate or carton and proper markers regarding handling precautions
are clearly marked on its crate or carton.
Batteries on racks shall be provided with earthquake bracings which hold
the sides of the batteries and prevent them from falling off the rack.For noise consideration, grounds may have to be separated as one of
the various possible means to help meet noise objectives and, in such
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case, the grounds may be insulated from each other except at the final
point of earth connection at the master ground bar or earth electrode.
Power cables are sized to limit the voltage drop due to resistance of the
cable and hole heating of the cables to a safe limit. The limits of
minimum voltage are critical to the operation of the equipment; therefore,
it is important that voltage drops in the cabling be carefully controlled.
Attempt should be made to limit the overall voltage drop from the battery
to the working equipment to a maximum of one volt. The final selection of
cable size should be generous since the calculation makes no allowance
for voltage drop due to items such as fuses, switches, etc.
Various battery voltage may be derived by connecting a number of cellsin series and in all cases the rule required is not violated. (See Electrical
Hazards).
Frames of battery chargers, battery enclosures if provided, and all
exposed metallic structures shall be bonded together and grounded,
meeting the required rule. (See Electrical Hazards).
Caustic soda or either acid neutralizing agents should be stored and
available in battery rooms for use in accidental electrolyte or acid
spillage.
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DEFINITION OF TERMS
Access a point of entry or a means of entry into a circuit
Accessible admitting close approach because not guarded
by locked doors, elevation or other effective
means.
Accessible par t a part so located that it can be contacted by a
person, either directly or by menas of a probe or
tool, or that is not recessed the required distance
behind an opening.
Accessories devices that perform a secondary or minor duty
as an adjunct or refinement to the primary or
major duty of a unit of equipment.
Acoustics the science of sound
Acoustic Shock the physical pain, dizzeness and sometimes
nausea caused by hearing a sudden very loud
sound. The threshold of pain is about 120 dBm.
Aging the change in properties of a material with time.
Air Gap a separating space between two magnetic
materials or conductors.
Alarm a visual or audible signal which alerts personnel
to the existence of an abnormal condition
Alive to have an electrical potential or charge different
from that of the earth.
Alpeth a type of telephone cable sheath featuring a
corrugated aluminium tape applied longitudinally
and a polyethelene jacket overall.
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American Wi re Gauge a scale of cross sectional measurement for non-
ferrous (copper, bronze, aluminium, etc.) wires
Ampere-Hour the quantity of electricity represented by a
current of one ampere that flows for one hour.
Anchor any device which holds something secure; a
device buried in the ground to which anchor rods
and guys are fastened.
Anhydr ous Antenna
dry; containing no water. A means for radiatingor receiving radio waves.
Appliance any device that uses or needs electricity or
usually an alectric current supply to perform a
certain function or operation; any equipment,
usually complete in itself, that transforms electric
energy into another form usually, visual, heat, or
motion at the point of utilization.
Arrester device which diverts high transient voltage to
ground and away from the equipment thus
protected; the voltage limiting portion of a
protector.
Ar rester Gas-Fi ll ed protector consisting of opposing spaced metal
electrodes within a sealed tube or enclosure filled
with gas such as neon or argon.
Assembly a grouping of components to accomplish a
particular function
Atmosphere, Explosive air holding in suspension dust, metal particles or
flammable gas in such proportions that may ignite
explosively
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Attachments all of the plant elements (cables, cross-arms,
brackets, etc) which are fastened to a supporting
structure such as a pole.
Audio pertaining to frequencies which can be heard by
the human ear.
Automatic describing the actions of a device or equipment
which are taken without human supervision in
response to certain pre-determined conditions.
Backbone the main system route, usually the route carrying
the majority of the traffic, and often the longest
series of cascaded hops.
Bandwith range of frequencies of a device, within which its
performance, in respect to some characteristics
conform to specified limits; the difference between
the upper and lower limits of the operating
frequency of the device.
Baseband band of frequencies occupied by the aggregate
of all the information signals used to modulate a
carrier.
Battery a group of two or more cells connected together
to furnish current by conversion of chemical,
thermal, solar or nuclear energy into electrical
energy.
Bond a low resistance electrical connection between
two cable sheaths, between two ground
connections or between similar parts of two
circuits.
Bus a conductor or group of conductors, that serve
as a common connection for two or more circuits.
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Cable assembly of insulated conductors into a
compact form which is covered by a flexible,
waterproof, protective covering.
Circuit the complete electrical path between terminals
over which telecommunications are provided.
Climbin g Space the vertical space reserved along the side of a
pole or tower to permit ready access for linemen
to equipment and conductors located thereon.
Conductor anything such as a wire or cable which is
suitable for the carrying of an electric current.
Communication transmitting and or receiving of information
signals, or messages between two or more points.
dB abbreviation for decibelwhich is one-tenth of a
bel. A unit expressing the ratio of two voltages,
currents or powers. It is equal to 20 times the
common logarithm of the ratio of the two voltages
or two currents and 10 times the common
logarithm of the ratio of the two powers.
Dropwire insulated wires, used to run a subscribers line
from the terminal on the pole to the protector at
the house or building.
Electronics the branch of science and technology which
deals with the control and utilization of electron
flow.
Electroni c Switchin g the selective interconnection of channels of
communication by means consisting essentially if
not entirely of electronic circuitry and circuit
elements.
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Explosion proof one that is designed and constructed to
withstand an explosion og a gas or vapour that
may occur within it or in its immediate vicinity and
to prevent the ignition of the gas or vapour
surrounding or within its enclosure.
Exposed Par t a part which can be inadvertently touched or
approached nearer than a safe distance.
Facility anything used or available for use in thefurnishing of communication service.
Facilities the elements used or available for use in the
furnishing of communication service, such as radio
facilities, outside plant facilities, indoor plant
facilities, etc.
Fault a physical condition that causes a device, a
component or a element to fail to perform in a
required manner.
Fault curr ent a current that flows from one conductor to
ground or to another conductor owing to any
abnormal connection (including an arc) between
the two.
Fl ame Proof apparatus so treated such that it will not
maintain a flame or will not be injured readily
when subjected to flame.
Fl ame Retarding property of materials or structures such that they
will not convey flame or continue to burn for longer
times than specified in the appropriate flame test.
Flashover a discharge through air, around or over the
surface of solid, liquid or other insulation, between
parts of different potential of polarity, produced by
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the application of voltage such that the breakdown
path becomes sufficiently ionized to maintain an
electric arc.
Fuse a device used for protection against excessive
currents. Consisting of a short length of fusible
metal strip which melts when the current through it
exceeds the rated amount for a definite time.
Ground a conducting connection, whether intentional or
accidental, by which an electric circuit orequipment is connected to earth, or to some
conducting body of relatively large extent that
serves in place of the earth.
Ground Bus a bus to which the grounds from individual
pieces of equipment are connected, and, that, in
turn, is connected to ground at one or more
points.
Ground Ring a configuration of grounding conductors arrange
around a structure such as building, tower footing,
tower guy anchor etc. normally connected to an
earth ground at one or more points.
Guy a tension member (of solid or stranded wires)
used to withstand an otherwise unbalanced force
on a pole or other overhead line structures.
Guy, Overhead a guy extending from a pole or structure or tree
and is sometimes called a span guy.
Guy, Anchor a guy which has its lower anchorage in the
earth.
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Guy Exposed a guy which has any part less than 2.5 meters
from the vertical plane of any electric power
conductor of more than 250 volts.
Guy in Proximi ty a guy which has any part within a vertical
distance of less than 2.5 meters from the level of
power conductors and a radial distance of less
than 1.8 meters from the surface of a wooden pole
or structure.
Guarded covered, shielded, fenced, enclosed, or
otherwise protected by means of suitable covers
or casings, barrier rails or screens, or platform to
remove the likelihood of dangerous contact with or
approach by persons or objects to a point of
danger.
Handhole an opening in an underground run or system
into which workers reach, but do not enter. A sub-
surface box having a cover flush with the ground.
Hazard any condition which imperils life, limb and
property.
Insulated separated from other conducting surfaces by a
dielectric substance or air space permanently
offering a high resistance to the passage of
current and to disruptive discharge through the
substance or space. When any object is said to be
insulated, it is understood to be insulated in
suitable manner for the conditions to which it is
subjected. Otherwise, it is, within the purpose of
this code, uninsulated.
Join t Use occupancy of poles or structures by two or more
different entities by mutual agreement.
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Li ghtning Ar rester a device designed to protect apparatus from
high transient voltage, by diverting surge current
to ground and capable of repeating this function
as specified.
Li nes, Communi cation the channels or conductors and their supporting
or containing components or structures usually
located outdoors which are used for
transmission/reception of information/intelligence
in communication service (telephone, telegraph,
data telemetering, video, etc.).
L in es, Power the conductors and their supporting or
containing structures which are located outdoors
used for transmitting a supply of electrical energy.
Maintenance all of the work required to keep the plant,
circuits, lines, facilities, systems and services up
to standards. This includes testing, trouble
clearing, repairing, and replacing defective
elements.
Manhole a subsurface chamber, large enough for a
person to enter, in the route of one or moreconduit runs, and affording facilities for placing
and maintaining in the runs, conductors, cables
and any associated apparatus.
Manual operated by mechanical force, applied directly
by personal intervention.
Messenger stranded steel wires in a group which generally
is not a part of the conducting system, its primary
function being to support wires or cables of the
system.
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apparatus, circuit or system and responsible for
the safety precautions involved.
Radiant Energy any energy which radiated in the form of radio
waves, infrared (heat) waves, light waves, x-rays.
etc.
Radiate the spreading out of radiant energy
Rod, Ground a metallic rod, driven into the ground to provide
an electrical connection to the earth.
Rod, Li ghtning a metallic rod carried above the highest point of
a pole or structure and connected to earth by a
heavy copper conductor intended to carry
lightning currents directly to earth.
Reconstruction that work which in any way changes the identity
of the plant or station or portions thereof.
Service Drop the installation from the terminal on the pole to
the protector at the customerspremises.
Sag the maximum departure, measured vertically, of
a wire or cable in a given span from a straight line
between the two points of support of the span at
60 degrees celcius and no wind loading.
Span the horizontal distance between two adjacent
supporting points of a cable or wire.
Supply Circui t the branch circuit supplying electrical energy to
the equipment or appliance.
System, Electron ic a configuration or arrangement of one or more
electronic equipment producing the desired
performance.
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Telecommunication any transmission, emission or reception of signs,
signals, writings, images, sounds or intelligence of
any nature by wire, radio, visual or other
electromagnetic system or such other system that
may in the future become known or developed.
Tensile Strength the pulling stress required to break a material,
such as a wire, expressed in kilograms of stress
per cross-sectional area.
Tension mechanical stress caused by forces which tendto stretch or severe the material stressed.
Tension, Maximum one-half of the tensile strength for messengers
Allowable guys, etc. and one-forth of the tensile strength for
communication cables and wires.
Tower Displacement the horizontal displacement of a point on the
tower axis from its no-wind load position at that
elevation.
Tower Sway tower sway at any specified elevation shall be
defined as the angular displacement of a tangent
to the tower axis at the elevation from its no-wind
load position at that elevation.
Tower Twist the horizontal angular displacement of the tower
from its no-wind position at that elevation.
Underground describing communication facilities installed
below the surface of the earth.
Working Space the space extending laterally from the climbing
space, reserved for working below, above and
between conductor levels; the space surrounding
a device or equipment.
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1. An electrical discharge which occurs between clouds and also from cloudto earth.
A. ThunderB. Lightning
C. CoronaD. Aurora
2. Results from abnormally high sound level, the physical effects of which
may vary from minor discomfort to serious injury.
A. Electrical ShockB. Super SonicC. Acoustic Shock
D. Sonic Boom
3. The factor that determines the intensity of electric shock is
A. currentB. voltageC. resistance
D. conductance
4. The average resistance of a dry adult human body is approximately:
A. 10 000 ohmsB. 100 000 ohmsC. 1 000 ohmsD. 100 ohms
5. Ventricular fibrillation is likely to occur when a 60Hz rms current ofamperes and above passes through oneschest cavity.
A. 0.010
B. 0.11
C. 0.030D. 0.33
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6. The minimum voltage value that is considered hazardous is:
A. 45V RMS AC
B. 12V RMS ACC. 24V RMS ACD. 50V RMS AC
7. The minimum voltage value that is considered hazardous is:
A. 150V DC
B. 45V DCC. 135V DCD. 160V DC
8. The potential difference at any time between two points on the floor orearth surface separated by a distance of one pace, or about one meter,in the direction of maximum potential gradient shall be no greater than
_.
A. 45 volts rms AC or 135 volts DCB. 25 volts rms AC or 115 volts DCC. 15 volts rms AC or 105 volts DC
D. 55 volts rms AC or 145 volts DC
9. It is the provision of a grounded electrical conducting material located
such that foreign potential will be intercepted and surge currents divertedto ground with the least damage to plant equipment possible.
A. Grounding
B. ShieldingC. BondingD. current limiting
10. Prevents development of hazardous potential difference incommunication plant by direct bonding, when permissible or by use ofsurge arresters, discharge gaps, diodes, etc. which operate under
abnormal voltage condition.
A. Current limitingB. Resistance limiting
C. GroundingD. Voltage Limiting
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11. The current in a circuit can be kept from rising above a predeterminedvalue by the use of a fuse in series with a circuit.
A. Current limitingB. Resistance limitingC. Grounding
D. Voltage Limiting
12. This is used to divert undesired currents before they reach theequipment being protected and often are installed both at and somedistance away from the protected equipment.
A. Current limitingB. Resistance limitingC. Grounding
D. Voltage Limiting
13. It is the resistance path of a ground connection which includes theground wire and its connection to ground electrode.
A. Ground ResistanceB. Ground ElectrodeC. Ground PathD. Resistance Path
14. For equipment locations, antenna towers, and all allied installations, the
ground resistance must never exceed .
A. 25 ohms
B. 3 ohmsC. 43 ohms
D. 5 ohms
15. For outside plant telephone poles and manholes as well as customer
premises, the ground resistance must never exceed _ _.
A. 25 ohmsB. 3 ohms
C. 43 ohmsD. 5 ohms
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21. The simplest way to make an earth resistance test is to use:
A. Direct Method or two terminal test *B. Voltmeter-Ammeter MethodC. Triangulation Method
D. Three terminal test
22. It is the resistance of parallel faces of a one cubic centimeter of soilexpressed in ohm-centimeter.
A. Ground resistanceB. Earth ResistivityC. Cubic resistanceD. Earth density
23. The following are ways to improve grounds except:
A. Lengthen the ground-electrode in the earthB. Use multiple rods
C. Treat the soil when 1 & 2 are not feasibleD. Place stones near the rod
24. Ground resistance shall be tested when installed and periodicallyafterwards, at least during the dry or non-rainy months and ALL
VALUES OBTAINED SHALL BE NO GREATER THAN THE RULE
REQUIRED.
A. 3 times per year
B. twice as yearC. once a year
D. 12 times a year
25. All ground connections, be it solderless or soldered, shall be checked at
least to be sure they are tight.
A. 3 times per yearB. twice as year
C. once a yearD. 12 times a year
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26. This loading shall be taken as the resultant stress due to wind and deadweight for 240 kph wind velocity.
A. Heavy Loading ZoneB. Medium Loading ZoneC. Light Loading Zone
D. Extra Heavy Loading Zone
27. This loading shall be taken as the resultant stress due to wind and deadweight for 200 kph wind velocity.
A. Heavy Loading ZoneB. Medium Loading ZoneC. Light Loading ZoneD. Extra Heavy Loading Zone
28. This loading shall be taken as the resultant stress due to wind and dead
weight for 160 kph wind velocity.
A. Heavy Loading ZoneB. Medium Loading ZoneC. Light Loading Zone
D. Extra Heavy Loading Zone
29. Batteries should be located where temperatures range between
_degrees Celsius.
A. 12.5 and 25.2B. 15.5 and 32.2
C. 15.2 and 52.2D. 55.5 and 60.3
30. Lead acid or similar gas emitting battery installations where theaggregate power exceeds _ _5 kilowatts shall be located in aproperly ventilated room separated from the equipment room or locationwhere people are staying.
A. 5 kW
B. 10 kWC. 1 kW
D. 15 kW
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31. Smoking and storing of inflammable materials is prohibited in batteryrooms and NO SMOKINGsigns should be posted _.
A. inside the room onlyB. before entering battery roomsC. outside the room only
D. Both A and C
32. An acid neutralizing agentsuch as should be stored and availablein battery rooms for use in accidental electrolyte or acid spillage.
A. oilB. keroseneC. flourD. Caustic soda
33. A low resistance electrical connection between two cable sheaths,
between two ground connections or between similar parts of two circuits.
A. Bond
B. ShortC. Fuse
D. Guy
34. The vertical space reserved along the side of a pole or tower to permit
ready access for linemen to equipment and conductors located thereon.
A. StairwayB. Climbing Space
C. guyD. pole
35. Insulated wires, used to run a subscribers line from the terminal on thepole to the protector at the house or building.
A. main lineB. main cableC. dropline
D. dropwire
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36. A physical condition that causes a device, a component or a element tofail to perform in a required manner.
A. damagedB. hazardC. fault
D. short
37. A current that flows from one conductor to ground or to anotherconductor owing to any abnormal connection (including an arc) between
the two.A. Fault current
B. Dark currentC. Leakage currentD. Dead short
38. An apparatus so treated such that it will not maintain a flame or will not
be injured readily when subjected to flame.
A. Flame ProofB. Flame Retarding
C. Burn proofD. Anti Flame
39. A property of materials or structures such that they will not convey flame
or continue to burn for longer times than specified in the appropriateflame test.
A. Flame ProofB. Flame RetardingC. Burn proofD. Anti Flame
40. A discharge through air, around or over the surface of solid, liquid orother insulation, between parts of different potential of polarity, produced
by the application of voltage such that the breakdown path becomessufficiently ionized to maintain an electric arc.
A. AuroraB. CoronaC. Flashover
D. Arc
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41. A conducting connection, whether intentional or accidental, by which anelectric circuit or equipment is connected to earth, or to some conducting
body of relatively large extent that serves in place of the earth.
A. shortB. jumper
C. groundD. link
42. A tension member (of solid or stranded wires) used to withstand anotherwise unbalanced force on a pole or other overhead line structures.
A. BondB. ShortC. Fuse
D. Guy
43. A guy extending from a pole or structure or tree and is sometimes calleda span guy.
A. Overhead guyB. Anchor guyC. bla guyD. Guy post
44. An opening in an underground run or system into which workers reach,
but do not enter.
A. Manhole
B. RatholeC. Handhole
D. finger hole
45. A device designed to protect apparatus from high transient voltage, by
diverting surge current to ground and capable of repeating this functionas specified.
A. Lightning ball
B. Lightning ArresterC. FuseD. Lightning Protector
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46. A subsurface chamber, large enough for a person to enter, in the route of
one or more conduit runs, and affording facilities for placing andmaintaining in the runs, conductors, cables and any associatedapparatus.
A. Manhole
B. Rathole
C. HandholeD. finger hole
47. Stranded steel wires in a group which generally is not a part of theconducting system, its primary function being to support wires or cables
of the system.
A. guy
B. supportC. conduit
D. messenger
48. A general term applied to the whole or portion of the physical property ofa communication company which contributes to the furnishing ofcommunication service.
A. zoneB. area
C. plantD. division
49. A metallic rod, driven into the ground to provide an electrical connectionto the earth.
A. Lightning rod
B. Ground rodC. Drop groundD. radials
50. A metallic rod carried above the highest point of a pole or structure andconnected to earth by a heavy copper conductor intended to carry
lightning currents directly to earth.A Lightning arrester
B. Lightning rodC. Breaker
D. Lightning gap
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51. The installation from the terminal on the pole to the protector at thecustomers premises.
A. Service dropB. Subscribers loop
C. Main lineD. Local drop
52. The horizontal displacement of a point on the tower axis from its no-windload position at that elevation.
A. Tower displacementB. Tower swayC. Tower Twist
D. Tower bend
53. The angular displacement of a tangent to the tower axis at the elevationfrom its no-wind load position at that elevation.
A. Tower displacementB. Tower sway
C. Tower TwistD. Tower bend
54. The horizontal angular displacement of the tower from its no-wind
position at that elevation.
A. Tower displacement
B. Tower swayC. Tower Twist
D. Tower bend
55. Refers to communication facilities installed below the surface of the
earth.
A. underneathB. underground
C. earth matD. under earth