Mike Holt Enterprises • www.MikeHolt.com • 888.NEC.CODE (632.2633) | v

ContentsAbout This Textbook ...........................................................................xiii

Additional Products to Help You Learn ..................................xvi

How to Use the National Electrical Code ................................ 1

Global Changes in the 2020 National Electrical Code ................................................................................................................. 9

Article 90—Introduction to the National Electrical Code ...............................................................................................................1190.2 Scope of the NEC ..........................................................................11

CHAPTER 1—GENERAL RULES ...........................................15

Article 100—Definitions ....................................................................17100 Definitions ......................................................................................17

Part III. Definitions, Hazardous (Classified) Locations ...........................21

Article 110—Requirements for Electrical Installations ..............................................................................................33110.3 Examination, Identification, Installation, Use, and

Product Listing (Certification) of Equipment ..............................33110.5 Conductor Material .......................................................................34110.12 Mechanical Execution of Work ....................................................34110.14 Conductor Termination and Splicing ...........................................36110.21 Markings ........................................................................................37110.22 Identification of Disconnecting Means .......................................38110.24 Available Fault Current .................................................................38110.26 Spaces About Electrical Equipment ............................................39110.28 Enclosure Types ............................................................................47

CHAPTER 2—WIRING AND PROTECTION ...................49

Article 200—Use and Identification of Grounded Conductors ................................................................................................51200.3 Connections to Grounded System ...............................................52200.6 Identification of Grounded Conductors .......................................52

200.9 Means of Identification .................................................................53

200.10 Identification of Terminals ............................................................54

Article 210—Branch Circuits ........................................................55210.5 Identification for Branch Circuits .................................................55210.6 Branch-Circuit Voltage Limitations ..............................................57210.8 GFCI Protection..............................................................................57210.11 Branch Circuits Required .............................................................67210.12 Arc-Fault Circuit-Interrupter Protection ......................................69210.15 Reconditioned Equipment ............................................................70210.19 Conductor Sizing ...........................................................................70210.52 Dwelling Unit Receptacle Outlet Requirements .........................72210.63 Equipment Requiring Servicing ...................................................78210.65 Meeting Rooms .............................................................................79210.70 Lighting Outlet Requirements ......................................................81

Article 215—Feeders ..........................................................................85215.2 Conductor Sizing ...........................................................................85215.9 Ground-Fault Circuit-Interrupter Protection for Personnel ........86

Article 220—Branch‑Circuit, Feeder, and Service Load Calculations .................................................................................87220.11 Floor Area ......................................................................................87220.12 Lighting Load for Non-Dwelling Occupancies ............................88220.14 Other Loads—Occupancies ..........................................................90220.16 Loads for Additions to Existing Installations ..............................92220.42 General Lighting Demand Factors ..............................................93220.53 Appliance Load, Dwelling .............................................................94220.60 Noncoincident Loads ....................................................................95220.87 Determining Existing Loads .........................................................96

Article 225—Outside Branch Circuits and Feeders .......99225.4 Conductor Covering ......................................................................99225.10 Wiring on Buildings (or Other Structures) ..................................99225.15 Supports over Buildings .............................................................100225.19 Clearances from Buildings .........................................................100225.30 Number of Supplies ....................................................................102

Article 230—Services ......................................................................105230.31 Underground Service Conductor Size and Ampacity ..............105230.42 Minimum Size and Ampacity .....................................................106

vi | Mike Holt’s Illustrated Guide to Changes to the National Electrical Code 2020

Article 240 | Contents

Part VI. Equipment Grounding and Equipment Grounding Conductors ....................................................................................................162250.109 Metal Enclosures .........................................................................162250.112 Specific Equipment Fastened in Place (Fixed) or

Connected by Permanent Wiring Methods...............................162250.114 Equipment Connected by Cord and Plug ..................................163250.119 Identification of Equipment Grounding Conductors ................164250.120 Equipment Grounding Conductor Installation ..........................165250.121 Restricted Use of Equipment Grounding Conductors .............166250.122 Sizing Equipment Grounding Conductors .................................166250.132 Short Sections of Raceway ........................................................170250.136 Equipment Secured to Grounded Metal Supports ..................171250.138 Cord-and-Plug-Connected Equipment.......................................171250.146 Connecting Receptacle Grounding Terminal to an

Equipment Grounding Conductor ..............................................172250.148 Continuity of Equipment Grounding Conductors in Boxes ......175

CHAPTER 3—WIRING METHODS AND MATERIALS .........................................................................................179

Article 300—General Requirements for Wiring Methods and Materials ...................................................................183300.3 Conductors ..................................................................................183300.4 Protection Against Physical Damage ........................................185300.7 Raceways Exposed to Different Temperatures ........................186300.22 Wiring in Ducts and Plenum Spaces .........................................186300.25 Exit Enclosures (Stair Towers) ...................................................187

Article 310—Conductors for General Wiring ....................189310.1 Scope ...........................................................................................189310.3 Conductors ..................................................................................190310.4 Conductor Construction and Applications ...............................191310.6 Conductor Identification .............................................................193310.10 Uses Permitted ............................................................................193310.12 Single-Phase Dwelling Services and Feeders ..........................194310.14 Ampacities for Conductors Rated 0V Through 2,000V ...........198310.15 Ampacity Tables ..........................................................................199310.16 Ampacities of Insulated Conductors in Raceways, Cables,

or Buried ......................................................................................207

Article 312—Cabinets ......................................................................209312.5 Enclosures ...................................................................................209312.6 Deflection of Conductors ............................................................211312.8 Overcurrent Device Enclosures .................................................211

230.43 Wiring Methods ...........................................................................106230.44 Cable Trays ..................................................................................107230.46 Spliced Conductors .....................................................................107230.62 Service Equipment—Enclosed or Guarded ...............................108230.66 Marking for Service Disconnect ................................................109230.67 Surge Protection .........................................................................110230.70 Service Disconnect Requirements ............................................111230.71 Number of Service Disconnects ................................................111230.82 Connected on Supply Side of the Service Disconnect ............112230.85 Emergency Disconnects .............................................................114

Article 240—Overcurrent Protection .....................................117240.2 Definitions ....................................................................................118240.5 Protection of Flexible Cords, Flexible Cables, and Fixture

Wires ............................................................................................118240.6 Standard Ampere Ratings ..........................................................119240.21 Location in Circuit .......................................................................119240.24 Location of Overcurrent Protective Devices at Premises .......123240.33 Vertical Position ..........................................................................125240.40 Disconnecting Means for Fuses ................................................125240.62 Reconditioned Equipment ..........................................................126240.67 Arc Energy Reduction--Fuses .....................................................126240.86 Series Ratings .............................................................................127240.87 Arc Energy Reduction—Circuit Breakers ..................................128240.88 Reconditioned Equipment ..........................................................129240.91 Protection of Conductors ...........................................................130

Article 242—Overvoltage Protection .....................................131242 Overvoltage Protection ...............................................................132

Article 250—Grounding and Bonding ....................................137250.6 Objectionable Current .................................................................137250.12 Clean Surfaces ............................................................................137250.20 Systems Required to be Grounded ...........................................138250.25 Grounding for Supply Side of the Service Disconnect ............139250.26 Conductor to Be Grounded-Alternating-Current Systems ......139250.28 Main Bonding Jumper and System Bonding Jumper..............140250.30 Separately Derived Systems ......................................................141250.32 Buildings Supplied by a Feeder .................................................148250.34 Generators—Portable and Vehicle- or Trailer-Mounted ...........149250.36 High-Impedance Grounded Systems.........................................150250.53 Grounding Electrode Installation Requirements ......................151250.64 Grounding Electrode Conductor Installation ............................152250.68 Grounding Electrode Conductor and Bonding Jumper

Connection to Grounding Electrodes ........................................156250.98 Bonding Loosely Jointed Metal Raceways ...............................157250.104 Bonding of Piping Systems and Exposed Structural Metal ....158

Mike Holt Enterprises • www.MikeHolt.com • 888.NEC.CODE (632.2633) | vii

Contents | Article 406

Article 356—Liquidtight Flexible Nonmetallic Conduit (Type LFNC) .........................................................................245356.10 Uses Permitted ............................................................................245

Article 358—Electrical Metallic Tubing (Type EMT) .......247358.10 Uses Permitted ............................................................................247

Article 380—Multioutlet Assemblies .....................................249380.12 Uses Not Permitted .....................................................................249

Article 392—Cable Trays ................................................................251392.10 Uses Permitted ............................................................................251392.18 Cable Tray Installations ..............................................................252392.30 Securing and Supporting ...........................................................252392.44 Expansion Splice Plates .............................................................252392.46 Bushed Conduit and Tubing .......................................................253

CHAPTER 4—EQUIPMENT FOR GENERAL USE .....255

Article 400—Flexible Cords and Flexible Cables ...........257400.12 Uses Not Permitted .....................................................................257400.17 Protection from Damage ............................................................259

Article 402—Fixture Wires............................................................261402.3 (Fixture Wire) Types ....................................................................261

Article 404—Switches .....................................................................263404.2 Switch Connections ....................................................................263404.4 Damp or Wet Locations ..............................................................265404.7 Indicating .....................................................................................266404.9 General-Use Snap Switches, Dimmers, and Control

Switches ......................................................................................267404.10 Mounting of General-Use Snap Switches, Dimmers, and

Control Switches .........................................................................269404.12 Grounding of Enclosures ............................................................269404.14 Rating and Use of Switches .......................................................270

Article 406—Receptacles and Attachment Plugs (Caps) .........................................................................................................271406.2 Definitions ....................................................................................271406.3 Receptacle Rating and Type ......................................................271406.4 General Installation Requirements ............................................273406.5 Receptacle Mounting..................................................................275406.7 Attachment Plugs, Cord Connectors and Flanged Surface

Devices .........................................................................................276406.9 Receptacles in Damp or Wet Locations ....................................277

Article 314—Outlet, Device, Pull, Junction Boxes; Conduit Bodies; and Handhole Enclosures .......................213314.16 Number of Conductors ...............................................................213314.17 Conductors That Enter Boxes or Conduit Bodies ....................219314.27 Outlet Box Requirements ...........................................................220314.29 Boxes, Conduit Bodies, and Handhole Enclosures to Be

Accessible ....................................................................................222

Article 320—Armored Cable (Type AC) ................................223320.23 In Accessible Attics or Roof Spaces .........................................223320.80 Conductor Ampacity ...................................................................223

Article 330—Metal‑Clad Cable (Type MC) ..........................225330.80 Conductor Ampacities ................................................................225

Article 334—Nonmetallic‑Sheathed Cable (Type NM) ....227334.30 Securing and Supporting ...........................................................227

Article 336—Power and Control Tray Cable (Type TC) ...................................................................................................229336.2 Definition ......................................................................................229336.10 Uses Permitted ............................................................................229

Article 338—Service‑Entrance Cable (Types SE and USE) ...................................................................................................231338.2 Definitions ....................................................................................231338.10 Uses Permitted ............................................................................232

Article 340—Underground Feeder and Branch‑Circuit Cable (Type UF) ....................................................................................235340.10 Uses Permitted ............................................................................235340.12 Uses Not permitted .....................................................................236

Article 342—Intermediate Metal Conduit (Type IMC) ...............................................................................................237342.10 Uses Permitted ............................................................................237342.14 Dissimilar Metals .........................................................................237

Article 344—Rigid Metal Conduit (Type RMC) ................239344.10 Uses Permitted ............................................................................239344.14 Dissimilar Metals .........................................................................239

Article 350—Liquidtight Flexible Metal Conduit (Type LFMC) ............................................................................................241350.10 Uses Permitted ............................................................................241350.12 Uses Not Permitted .....................................................................242350.30 Securing and Supporting ...........................................................242

viii | Mike Holt’s Illustrated Guide to Changes to the National Electrical Code 2020

Article 408 | Contents

Article 430—Motors, Motor Circuits, and Controllers ...............................................................................................309430.2 Definitions ....................................................................................309430.32 Continuous-Duty Motors ............................................................310430.99 Available Fault Current ...............................................................310430.122 Conductor Sizing .........................................................................311430.130 Branch-Circuit Short-Circuit and Ground-Fault Protection ......313

Article 440—Air‑Conditioning and Refrigeration Equipment ................................................................................................315440.9 Grounding and Bonding ..............................................................315440.10 Short-Circuit Current Rating.......................................................316440.32 Single Motor-Compressor ..........................................................316

Article 445—Generators .................................................................319445.6 Listing ...........................................................................................319445.18 Disconnecting Means and Emergency Shutdown ...................319

Article 450—Transformers ...........................................................321450.9 Ventilation ....................................................................................321450.14 Disconnecting Means .................................................................322

Article 480—Storage Batteries .................................................323480.2 Definitions ....................................................................................323480.4 Battery and Cell Terminations ...................................................324480.7 DC Disconnect Methods .............................................................324480.10 Battery Locations ........................................................................325480.12 Battery Interconnections ............................................................326480.13 Ground-Fault Detection ..............................................................326

CHAPTER 5—SPECIAL OCCUPANCIES .......................327

Article 500—Hazardous (Classified) Locations .............329500.1 Scope—Articles 500 Through 503 Informational Notes .........330500.4 Documentation ............................................................................330500.5 Classifications of Hazardous Locations ....................................331500.7 Protection Techniques ................................................................332500.8 Equipment Involving Optical Radiation .....................................333

Article 501—Class I Hazardous (Classified) Locations ..................................................................................................335501.10 Wiring Methods ...........................................................................335501.15 Raceway and Cable Seals ..........................................................336501.105 Meters, Instruments, and Relays...............................................338

406.10 Grounding-Type Receptacles, Adapters, Cord Connectors, and Attachment Plugs ................................................................278

406.12 Tamper-Resistant Receptacles ..................................................278

Article 408—Switchboards and Panelboards ..................281408.3 Arrangement of Busbars and Conductors ................................281408.4 Field Identification .......................................................................281408.6 Short-Circuit Current Rating.......................................................282408.8 Reconditioning of Equipment ....................................................283408.18 Clearances ...................................................................................284408.23 Power Monitoring and Energy Management Equipment ........285408.36 Overcurrent Protection ...............................................................285408.43 Panelboard Orientation...............................................................285

Article 410—Luminaires, Lampholders, and Lamps .........................................................................................................287410.2 Definitions ....................................................................................287410.7 Reconditioned Equipment ..........................................................288410.10 Luminaires in Specific Locations ..............................................288410.16 Luminaires in Clothes Closets ...................................................289410.22 Outlet Boxes to Be Covered .......................................................291410.36 Means of Support .......................................................................291410.40 General .........................................................................................291410.44 Methods of Grounding, Exceptions ...........................................292410.116 Clearance and Installation ..........................................................292410.118 Access to Other Boxes................................................................293

Part XVI. Special Provisions for Horticultural Lighting Equipment .....................................................................................................293

Article 411—Low‑Voltage Lighting .........................................295411.4 Listing Required ..........................................................................295

Article 422—Appliances .................................................................297422.5 GFCI Protection............................................................................297422.6 Listing Required ..........................................................................299422.10 Branch Circuits ............................................................................299422.13 Storage-Type Water-Heaters ......................................................300422.16 Flexible Cords ..............................................................................301422.19 Space for Conductors .................................................................302422.22 Utilizing Separable Attachment Fittings ...................................303422.31 Permanently Connected Appliance Disconnects.....................303

Article 424—Fixed Electric Space‑Heating Equipment ................................................................................................305424.1 Scope ...........................................................................................305424.4 Branch Circuits, Branch-Circuit Requirements ........................306424.19 Disconnecting Means .................................................................307424.44 Electric Heating Cables in Concrete or Masonry Floors..........308

Mike Holt Enterprises • www.MikeHolt.com • 888.NEC.CODE (632.2633) | ix

Contents | Article 625

550.15 Wiring Methods and Materials ...................................................368

Article 555—Marinas, Boatyards, and Docking Facilities ....................................................................................................369555 Marinas, Boatyards, Floating Buildings, and Commercial

and Noncommercial Docking Facilities ....................................369555.1 Scope ...........................................................................................369555.2 Definitions ....................................................................................370555.3 Electrical Datum Plane Distances .............................................371555.4 Location of Service Equipment .................................................373555.5 Maximum Voltage .......................................................................373555.7 Transformers ...............................................................................373555.9 Boat Hoists...................................................................................374555.13 Bonding of Noncurrent-Carrying Metal Parts ..........................374

Part II. Marinas, Boatyards, and Docking Facilities ..............................375555.30 Electrical Connections ................................................................375555.33 Receptacles .................................................................................376555.34 Wiring Methods and Installation ................................................376555.35 Ground-Fault Protection of Equipment (GFPE) and Ground-

Fault Circuit-Interrupter (GFCI) Protection ................................376555.37 Equipment Grounding Conductor ..............................................377

Part III. Floating Buildings ..........................................................................378

Article 590—Temporary Installations ...................................379590.4 General .........................................................................................379590.6 GFCI Protection for Personnel ....................................................380590.8 Overcurrent Protective Devices .................................................380

CHAPTER 6—SPECIAL EQUIPMENT ..............................381

Article 600—Electric Signs and Outline Lighting ..........383600.2 Definitions ....................................................................................383600.3 Listing ...........................................................................................384600.4 Markings ......................................................................................385600.5 Branch Circuits ............................................................................385600.6 Disconnecting Means .................................................................387600.35 Retrofit Kits ..................................................................................389

Article 620—Elevators, Escalators, and Moving Walks, Platform Lifts, and Stairway Chair Lifts ............391620.6 GFCI Protection for Personnel ....................................................391620.22 Branch Circuits for Elevator Car(s) ............................................392620.51 Disconnecting Means .................................................................393

Article 502—Class II Hazardous (Classified) Locations ..................................................................................................339502.10 Wiring Methods ...........................................................................339502.150 Signaling, Alarm, Remote-Control, and Communications

Systems; Meters, Instruments, and Relays ..............................342

Article 503—Class III Hazardous (Classified) Locations ..................................................................................................343503.10 Wiring Methods ...........................................................................343

Article 511—Commercial Garages, Repair and Storage ......................................................................................................345511.1 Scope ...........................................................................................345511.3 Area Classification, General .......................................................346511.8 Underground Wiring Below Class I Locations ..........................346511.12 Ground-Fault Circuit-Interrupter Protection for Personal ........347

Article 514—Motor Fuel Dispensing Facilities ................349514.1 Scope ...........................................................................................349514.3 Classification of Locations .........................................................350514.11 Emergency Electrical Disconnects ............................................350

Article 517—Health Care Facilities .........................................351517 Health Care Facilities ..................................................................351517.2 Definitions ....................................................................................352517.10 Applicability .................................................................................352517.13 Equipment Grounding Conductor for Receptacles and

Fixed Electrical Equipment in Patient Care Spaces .................353517.16 Use of Isolated Ground Receptacles .........................................356

Article 518—Assembly Occupancies .....................................359518.6 Illumination ..................................................................................359

Article 525—Carnivals, Circuses, Fairs, and Similar Events .........................................................................................................361525.20 Wiring Methods ...........................................................................361525.23 GFCI-Protection............................................................................362

Article 547—Agricultural Buildings ........................................363547.2 Definitions ....................................................................................363547.5 Wiring Methods ...........................................................................364547.9 Electrical Supply to Buildings or Structures from a

Distribution Point.........................................................................365

Article 550—Mobile Homes, Manufactured Homes, and Mobile Home Parks .................................................................367550.13 Receptacle Outlets ......................................................................367

x | Mike Holt’s Illustrated Guide to Changes to the National Electrical Code 2020

Article 625 | Contents

690.11 Arc-Fault Circuit Protection (Direct Current) ............................438690.12 Rapid Shutdown of PV Systems on Buildings ..........................438690.13 Photovoltaic System Disconnecting Means .............................440690.15 Disconnecting Means for Isolating Photovoltaic Equipment ..443

Part IV. Wiring Methods and Materials ....................................................445690.31 Wiring Methods ...........................................................................445690.33 Connectors ..................................................................................452690.41 System Grounding ......................................................................453690.43 Equipment Grounding and Bonding ..........................................454690.45 Size of Equipment Grounding Conductors ...............................456690.47 Grounding Electrode System .....................................................457690.51 Modules and Alternating-Current Modules ..............................457690.53 DC PV Circuits ..............................................................................458690.56 Identification of Power Sources.................................................458

Article 691—Large‑Scale Photovoltaic (PV) Electric Supply Stations ....................................................................................461691.1 Scope ...........................................................................................461691.9 Disconnecting Means for Isolating Photovoltaic Equipment .....462691.11 Fence Bonding and Grounding ..................................................463

Article 694—Wind Electric Systems ......................................465694.22 Additional Provisions ..................................................................465694.54 Identification of Power Sources.................................................466

Article 695—Fire Pumps ................................................................467695.3 Power Source(s) for Electric Motor-Driven Fire Pumps ..........467695.4 Continuity of Power .....................................................................468695.6 Power Wiring ...............................................................................469695.10 Listed Equipment ........................................................................470

CHAPTER 7—SPECIAL CONDITIONS ............................471

Article 700—Emergency Systems ...........................................473700.2 Definitions ....................................................................................473700.4 Capacity and Rating ....................................................................474700.5 Transfer Equipment ....................................................................474700.6 Signals ..........................................................................................474700.12 General Requirements ................................................................475700.16 Emergency Illumination ..............................................................477700.32 Selective Coordination, Informational Note and

Informational Note Figure ..........................................................478

Article 701—Legally Required Standby Systems ..........481701.4 Capacity and Rating ....................................................................481701.5 Transfer Equipment ....................................................................481701.12 General Requirements ................................................................482

Part IV. Overcurrent Protection .................................................................483

Article 625—Electric Vehicle Power Transfer System ........................................................................................................395625.1 Scope ...........................................................................................396625.2 Definitions ....................................................................................396625.5 Listed ............................................................................................397625.41 Overcurrent Protection ...............................................................398625.42 Rating ...........................................................................................398625.48 Interactive Systems ....................................................................399625.54 GFCI Protection for Personnel ....................................................399625.60 AC Receptacle Outlets Used for EVPE ......................................400

Article 645—Information Technology Equipment (ITE) .............................................................................................................401645.5 Supply Circuits and Interconnecting Cables ............................401

Article 680—Swimming Pools, Spas, Hot Tubs, Fountains, and Similar Installations ......................................403680.2 Definitions ....................................................................................403680.3 Approval of Equipment ...............................................................405680.4 Inspections After Installation .....................................................406680.5 Ground-Fault Circuit Interrupters ...............................................406680.6 Bonding and Equipment Grounding ..........................................407680.7 Bonding and Equipment Grounding Terminals ........................407680.11 Underground Wiring....................................................................408680.14 Wiring Methods in Corrosive Environment ...............................408680.21 Motors (for permanently installed pools) .................................409680.22 Lighting, Receptacles, and Equipment .....................................411680.23 Underwater Pool Luminaires .....................................................413680.25 Feeders ........................................................................................415680.26 Equipotential Bonding ................................................................415

Part III. Storable Pools, Storable Spas, Storable Hot Tubs, and Storable Immersion Pools ..........................................................................419680.31 Pumps ..........................................................................................419680.35 Storable and Portable Immersion Pools ...................................419680.45 Permanently Installed Immersion Pools ...................................420680.50 General .........................................................................................420680.54 Grounding and Bonding ..............................................................421680.59 GFCI Protection for Permanently Installed Nonsubmersible

Pumps ..........................................................................................421680.80 General .........................................................................................422680.84 Switching Devices and Receptacles .........................................422

Article 690—Solar Photovoltaic (PV) Systems ...............423690.2 Definitions ....................................................................................423690.4 General Requirements ................................................................428690.6 Alternating-Current Modules and Systems ..............................429690.7 Maximum Voltage .......................................................................430690.8 Circuit Sizing and Current ...........................................................431690.9 Overcurrent Protection ...............................................................436

Mike Holt Enterprises • www.MikeHolt.com • 888.NEC.CODE (632.2633) | xi

Contents | Article 800

Article 712—Direct Current Microgrids ...............................525712.2 Definitions ....................................................................................525712.10 Directory ......................................................................................525712.25 Identification of Circuit Conductors ...........................................526712.34 DC Source Disconnecting Means ..............................................526712.65 Available DC Fault Current .........................................................526

Article 725—Remote‑Control, Signaling, and Power‑Limited Circuits ....................................................................527725.2 Definitions ....................................................................................527725.3 Other Articles ...............................................................................528725.24 Mechanical Execution of Work, Informational Note ................532725.48 Conductors of Different Circuits in the Same Cable, Cable

Tray, Enclosure, or Raceway ......................................................533725.121 Power Sources for Class 2 and Class 3 Circuits ......................534725.135 Installation of Class 2 Cables .....................................................535725.139 Conductors of Different Circuits in Same Cable, Enclosure,

Cable Tray, Raceway, or Cable Routing Assembly ...................536725.144 Transmission of Power and Data ...............................................536

Article 760—Fire Alarm Systems .............................................539760.3 Other Articles ...............................................................................539760.24 Mechanical Execution of Work ..................................................540760.121 Power Sources for Power-Limited Fire Alarm Circuits ............541

Article 770—Optical Fiber Cables and Raceways .........543770 Informational Note ......................................................................543770.24 Mechanical Execution of Work ..................................................543

CHAPTER 8—COMMUNICATIONS SYSTEMS ........545

Article 800—General Requirements for Communications Systems ............................................................547800.1 Scope ...........................................................................................547800.2 Definitions ....................................................................................548800.3 Other Articles ...............................................................................549800.49 Metal Entrance Conduit Grounding ...........................................551800.53 Separation from Lighting Conductors.......................................551800.100 Cable and Primary Protector Bonding and Grounding ............551800.110 Raceways, Cable Routing Assemblies, and Cable Trays ........555800.113 Installation of Wires, Cables, Cable Routing Assemblies,

and Communications Raceways ...............................................557800.154 Applications of Listed Communications Wires, Cables,

and Raceways, and Listed Cable Routing Assemblies ...........558800.179 Plenum, Riser, General-Purpose, and Limited Use Cables ......559

Article 702—Optional Standby Systems .............................485702.2 Definition ......................................................................................485702.4 Capacity and Rating ....................................................................486702.5 Transfer Equipment ....................................................................487702.7 Signs .............................................................................................488

Article 705—Interconnected Electric Power Production Sources ..........................................................................491705.2 Definitions ....................................................................................491705.6 Equipment Approval ...................................................................492705.10 Identification of Power Sources.................................................492705.11 Supply-Side Source Connections ..............................................493705.12 Load-Side Source Connections .................................................495705.13 Power Control Systems ..............................................................501705.20 Disconnecting Means, Source ...................................................502705.25 Wiring Methods ...........................................................................504705.28 Circuit Sizing and Current ...........................................................504705.30 Overcurrent Protection ...............................................................505705.32 Ground Fault Protection .............................................................506705.40 Loss of Primary Source ..............................................................507705.45 Unbalanced Interconnections ....................................................508

Parts II and III ...............................................................................................509705.50 System Operation .......................................................................509705.60 Primary Power Source Connection ...........................................509705.70 Microgrid Interconnect Devices (MID) ......................................510

Article 706—Energy Storage Systems .................................511706.1 Scope ...........................................................................................511706.2 Definitions ....................................................................................512706.3 Qualified Personnel .....................................................................513706.4 System Requirements ................................................................514706.5 Listing ...........................................................................................514706.7 Maintenance ................................................................................514706.9 Maximum Voltage .......................................................................515

Part II. Disconnecting Means ....................................................................515706.16 Connection to Energy Sources ..................................................517

Part III. Installation Requirements ............................................................517706.21 Directory (Identification of Power Sources) .............................518

Part IV. Circuit Requirements ....................................................................519706.30 Circuit Sizing and Current ...........................................................519706.31 Overcurrent Protection ...............................................................520

Article 710—Stand‑Alone Systems .........................................521710.1 Scope ...........................................................................................521710.6 Equipment Approval ...................................................................522710.10 Identification of Power Sources.................................................523710.12 Stand-Alone Inverter Input Circuit Current ...............................523710.15 General .........................................................................................523

xii | Mike Holt’s Illustrated Guide to Changes to the National Electrical Code 2020

Article 805 | Contents

2020 National Electrical Code Changes Review Quiz ............................................................................................569

About the Author .................................................................................579

About the Illustrator .........................................................................580

About the Mike Holt Team ............................................................581

Article 805—General Requirements for Communications Circuits ..............................................................561805.93 Grounding, Bonding, or Interruption of Non-Current-

Carrying Metallic Sheath Members of Communications Cables ...........................................................................................561

805.133 Installation of Communications Wires, Cables, and Equipment ....................................................................................562

805.154 Substitutions of Listed Communications Wires, Cables, and Raceways, and Listed Cable Routing Assemblies ...........563

Article 810—Radio and Television Satellite Equipment ................................................................................................565810.21 Bonding Conductors and Grounding Electrode

Conductors---Receiving Stations ...............................................565

Article 820—Community Antenna Television (CATV) and Radio Distribution Systems (Coaxial Cable) ..........567820.3 Other Articles ...............................................................................567820.44 Overhead (Aerial) Coaxial Cables ..............................................567820.100 Cable Bonding and Grounding ...................................................568820.154 Substitutions of Listed CATV Cables .........................................568