NFPA 70H-2017 National Electrical Code Handbook (Fourteenth Edition Includes Tentative Interim Amendment 2 December 1 2016 Effective Date December 21 2016).pdf

1、National Electrical Code Handbook 2017 iContentsWith the complete text of the 2017 edition of NFPA 70, National Electrical CodeNational Electrical Code HandbookEdited byMark W. Earley, P.E.Editor-in-ChiefChristopher D. CoacheMark CloutierGil MonizDerek VigstolFourteenth EditionInternational Electric

2、al Code SeriesNATIONAL FIRE PROTECTION ASSOCIATIONThe leading information and knowledge resource on f_ire, electrical and related hazards70HB17_CH00_FM_i_xiv.indd 1 10/11/16 8:57 AMProduct Management: Debra RoseDevelopment and Production: Kenneth RitchieCopyediting: Cara GradyPermissions: Josiane Do

3、meniciInterior Design: Cheryl LangwayCover Design: Cameron, Inc.Composition: Shepherd, Inc.Printing and Binding: LSC Communications, Inc.Copyright 2016National Fire Protection AssociationOne Batterymarch ParkQuincy, Massachusetts 02169-7471All rights reserved. Important Notices and Disclaimers: Publ

4、ication of this handbook is for the purpose of circulating information and opinion among those concerned for fire and electrical safety and related subjects. While every effort has been made to achieve a work of high quality, neither the NFPAnor the contributors to this handbook guarantee or warrant

5、ee the accuracy or completeness of or assume any liability in connection with the information and opinions contained in this handbook. The NFPA and the contributors shall in no event be liable for any personal injury, property, or other damages of any nature whatsoever, whether special, indirect, co

6、nsequential, or compensatory, directly or indirectly resulting from the publication, use of, or reliance upon this handbook.This handbook is published with the understanding that the NFPA and the contributors to this handbook are supplying information and opinion but are not attempting to render eng

7、ineering or other professional services. If such services are required, the assistance of an appropriate professional should be sought.NFPA 70, National Electrical Code(“NFPA 70”), is, like all NFPA codes, standards, recommended practices, and guides (“NFPA Standards”), made available for use subjec

8、t to Important Notices and Legal Disclaimers, which appear at the end of this handbook and can also be viewed at www.nfpa.org/disclaimers.Notice Concerning Code Interpretations: This fourteenth edition of the National Electrical CodeHandbook is based on the 2017 edition of NFPA 70. All NFPA codes, s

9、tandards, recommended practices, and guides (“NFPA Standards”) are developed in accordance with the published procedures of the NFPA by technical committees comprised of volunteers drawn from a broad array of relevant interests. The handbook contains the complete text of NFPA 70 and any applicable F

10、ormal Interpretations issued by the NFPA at the time of publication. This NFPA Standard is accompanied by explanatory commentary and other supplementary materials.The commentary and supplementary materials in this handbook are not a part of the NFPA Standard and do not constitute Formal Interpretati

11、ons of the NFPA (which can be obtained only through requests processed by the responsible technical committees in accordance with the published procedures of the NFPA). The commentary and supplementary materials, therefore, solely reflect the personal opinions of the editor or other contributors and

12、 do not necessarily represent the official position of the NFPA or its technical committees.REMINDER: UPDATING OF NFPA STANDARDSNFPA 70, National Electrical Code, like all NFPA codes, standards, recommended practices, and guides (“NFPA Standards”), may be amended from time to time through the issuan

13、ce of Tentative Interim Amendments or corrected by Errata. An official NFPA Standard at any point in time consists of the current edition of the document together with any Tentative Interim Amendment and any Errata then in effect. In order to determine whether an NFPA Standard has been amended throu

14、gh the issuance of Tentative Interim Amendments or corrected by Errata, visit the “Codes Conduit Bodies; Fittings; and Handhole Enclosures 289Article 320 Armored Cable: Type AC 304Article 322 Flat Cable Assemblies: Type FC 307Article 324 Flat Conductor Cable: Type FCC 309Article 326 Integrated Gas S

15、pacer Cable: Type IGS 312Article 328 Medium Voltage Cable: Type MV 313Article 330 Metal-Clad Cable: Type MC 314Article 332 Mineral-Insulated, Metal-Sheathed Cable: Type MI 318Article 334 Nonmetallic-Sheathed Cable: Types NM, NMC, and NMS 320Article 336 Power and Control Tray Cable: Type TC 325Articl

16、e 338 Service-Entrance Cable: Types SE and USE 327Article 340 Underground Feeder and Branch-Circuit Cable: Type UF 329Article 342 Intermediate Metal Conduit: Type IMC 330Article 344 Rigid Metal Conduit: Type RMC 333Article 348 Flexible Metal Conduit: Type FMC 337Article 350 Liquidtight Flexible Meta

17、l Conduit: Type LFMC 339Article 352 Rigid Polyvinyl Chloride Conduit: Type PVC 341Article 353 High Density Polyethylene Conduit: Type HDPE Conduit 345Article 354 Nonmetallic Underground Conduit with Conductors: Type NUCC 346Article 355 Reinforced Thermosetting Resin Conduit: Type RTRC 348Article 356

18、 Liquidtight Flexible Nonmetallic Conduit: Type LFNC 351Article 358 Electrical Metallic Tubing: Type EMT 353Article 360 Flexible Metallic Tubing: Type FMT 356Article 362 Electrical Nonmetallic Tubing: Type ENT 358Article 366 Auxiliary Gutters 362Article 368 Busways 365Article 370 Cablebus 369Article

19、 372 Cellular Concrete Floor Raceways 371Article 374 Cellular Metal Floor Raceways 372Article 376 Metal Wireways 374Article 378 Nonmetallic Wireways 376Article 380 Multioutlet Assembly 378Article 382 Nonmetallic Extensions 378Article 384 Strut-Type Channel Raceway 381Article 386 Surface Metal Racewa

20、ys 383Article 388 Surface Nonmetallic Raceways 384Article 390 Underfloor Raceways 386Article 392 Cable Trays 387Article 393 Low-Voltage Suspended Ceiling Power Distribution Systems 397Contents70HB17_CH00_FM_i_xiv.indd 5 10/11/16 8:57 AMvi 2017 National Electrical Code HandbookContentsArticle 394 Con

21、cealed Knob-and-Tube Wiring 400Article 396 Messenger-Supported Wiring 402Article 398 Open Wiring on Insulators 403Article 399 Outdoor Overhead Conductors over 1000 Volts 405Chapter 4 Equipment for General Use 406Article 400 Flexible Cords and Flexible Cables 406Article 402 Fixture Wires 417Article 4

22、04 Switches 421Article 406 Receptacles, Cord Connectors, and Attachment Plugs (Caps) 427Article 408 Switchboards, Switchgear, and Panelboards 435Article 409 Industrial Control Panels 443Article 410 Luminaires, Lampholders, and Lamps 445Article 411 Low-Voltage Lighting 461Article 422 Appliances 462Ar

23、ticle 424 Fixed Electric Space-Heating Equipment 469Article 425 Fixed Resistance and Electrode Industrial Process Heating Equipment 480Article 426 Fixed Outdoor Electric Deicing and Snow-Melting Equipment 485Article 427 Fixed Electric Heating Equipment for Pipelines and Vessels 489Article 430 Motors

24、, Motor Circuits, and Controllers 492Article 440 Air-Conditioning and Refrigerating Equipment 537Article 445 Generators 546Article 450 Transformers and Transformer Vaults (Including Secondary Ties) 549Article 455 Phase Converters 563Article 460 Capacitors 565Article 470 Resistors and Reactors 568Art

25、icle 480 Storage Batteries 569Article 490 Equipment Over 1000 Volts, Nominal 572Chapter 5 Special Occupancies 581Article 500 Hazardous (Classified) Locations, Classes I, II, and III, Divisions 1 and 2 581Article 501 Class I Locations 593Article 502 Class II Locations 614Article 503 Class III Locatio

26、ns 621Article 504 Intrinsically Safe Systems 625Article 505 Zone 0, 1, and 2 Locations 631Article 506 Zone 20, 21, and 22 Locations for Combustible Dusts or Ignitible Fibers/Flyings 647Article 510 Hazardous (Classified) Locations Specific 655Article 511 Commercial Garages, Repair and Storage 655Arti

27、cle 513 Aircraft Hangars 661Article 514 Motor Fuel Dispensing Facilities 665Article 515 Bulk Storage Plants 673Article 516 Spray Application, Dipping, Coating, and Printing Processes Using Flammable or Combustible Materials 679Article 517 Health Care Facilities 692Article 518 Assembly Occupancies 71

28、8Article 520 Theaters, Audience Areas of Motion Picture and Television Studios, Performance Areas, and Similar Locations 722Article 522 Control Systems for Permanent Amusement Attractions 737Article 525 Carnivals, Circuses, Fairs, and Similar Events 739Article 530 Motion Picture and Television Studi

29、os and Similar Locations 743Article 540 Motion Picture Projection Rooms 747Article 545 Manufactured Buildings 749Article 547 Agricultural Buildings 750Article 550 Mobile Homes, Manufactured Homes, and Mobile Home Parks 754Article 551 Recreational Vehicles and Recreational Vehicle Parks 765Article 55

30、2 Park Trailers 780Article 553 Floating Buildings 791Article 555 Marinas, Boatyards, and Commercial and Noncommercial Docking Facilities 792Article 590 Temporary Installations 798Chapter 6 Special Equipment 802Article 600 Electric Signs and Outline Lighting 802Article 604 Manufactured Wiring Systems

31、 811Article 605 Office Furnishings 813Article 610 Cranes and Hoists 815Article 620 Elevators, Dumbwaiters, Escalators, Moving Walks, Platform Lifts, and Stairway Chairlifts 822Article 625 Electric Vehicle Charging System 836Article 626 Electrified Truck Parking Spaces 844Article 630 Electric Welders

32、 849Article 640 Audio Signal Processing, Amplification, and Reproduction Equipment 853Article 645 Information Technology Equipment 860Article 646 Modular Data Centers 865Article 647 Sensitive Electronic Equipment 870Article 650 Pipe Organs 872Article 660 X-Ray Equipment 873Article 665 Induction and

33、Dielectric Heating Equipment 87670HB17_CH00_FM_i_xiv.indd 6 10/11/16 8:57 AMNational Electrical Code Handbook 2017 viiContentsArticle 668 Electrolytic Cells 879Article 669 Electroplating 882Article 670 Industrial Machinery 883Article 675 Electrically Driven or Controlled Irrigation Machines 885Artic

34、le 680 Swimming Pools, Fountains, and Similar Installations 888Article 682 Natural and Artificially Made Bodies of Water 911Article 685 Integrated Electrical Systems 914Article 690 Solar Photovoltaic (PV) Systems 914Article 691 Large-Scale Photovoltaic (PV) Electric Power Production Facility 932Arti

35、cle 692 Fuel Cell Systems 933Article 694 Wind Electric Systems 936Article 695 Fire Pumps 941Chapter 7 Special Conditions 955Article 700 Emergency Systems 955Article 701 Legally Required Standby Systems 969Article 702 Optional Standby Systems 973Article 705 Interconnected Electric Power Production So

36、urces 976Article 706 Energy Storage Systems 982Article 708 Critical Operations Power Systems (COPS) 989Article 710 Stand-Alone Systems 995Article 712 Direct Current Microgrids 996Article 720 Circuits and Equipment Operating at Less Than 50 Volts 997Article 725 Class 1, Class 2, and Class 3 Remote-Co

37、ntrol, Signaling, and Power-Limited Circuits 998Article 727 Instrumentation Tray Cable: Type ITC 1014Article 728 Fire-Resistive Cable Systems 1016Article 750 Energy Management Systems 1017Article 760 Fire Alarm Systems 1017Article 770 Optical Fiber Cables 1033Chapter 8 Communications Systems 1044Art

38、icle 800 Communications Circuits 1044Article 810 Radio and Television Equipment 1063Article 820 Community Antenna Television and Radio Distribution Systems 1069Article 830 Network-Powered Broadband Communications Systems 1080Article 840 Premises-Powered Broadband Communications Systems 1095Chapter 9

39、 Tables 1101Table 1 Percent of Cross Section of Conduit and Tubing for Conductors and Cables 1101Table 2 Radius of Conduit and Tubing Bends 1105Table 4 Dimensions and Percent Area of Conduit and Tubing (Areas of Conduit or Tubing for the Combinations of Wires Permitted in Table 1, Chapter 9) 1105Tab

40、le 5 Dimensions of Insulated Conductors and Fixture Wires 1110Table 5A Compact Copper and Aluminum Building Wire Nominal Dimensions and Areas 1114Table 8 Conductor Properties 1115Table 9 Alternating-Current Resistance and Reactance for 600-Volt Cables, 3-Phase, 60 Hz, 75C (167F) Three Single Conduct

41、ors in Conduit 1116Table 10 Conductor Stranding 1119Table 11(A) Class 2 and Class 3 Alternating-Current Power Source Limitations 1120Table 11(B) Class 2 and Class 3 Direct-Current Power Source Limitations 1120Table 12(A) PLFA Alternating-Current Power Source Limitations 1121Table 12(B) PLFA Direct-C

42、urrent Power Source Limitations 1121AnnexesInformative Annex A Product Safety Standards 1122Informative Annex B Application Information for Ampacity Calculation 1128Informative Annex C Conduit and Tubing Fill Tables for Conductors and Fixture Wires of the Same Size 1142Informative Annex D Examples 1

43、222Informative Annex E Types of Construction 1235Informative Annex F Availability and Reliability for Critical Operations Power Systems; and Development and Implementation of Functional Performance Tests (FPTs) for Critical Operations Power Systems 1238Informative Annex G Supervisory Control and Dat

44、a Acquisition (SCADA) 1241Informative Annex H Administration and Enforcement 1243Informative Annex I Recommended Tightening Torque Tables from UL Standard 486A-B 1251Informative Annex J ADA Standards for Accessible Design 1253Index 125670HB17_CH00_FM_i_xiv.indd 7 10/13/16 9:29 AM70HB17_CH00_FM_i_xiv

45、.indd 8 10/11/16 8:57 AMixThis handbook contains the 54th edition of the National Electrical Code. Nearly 120 years have passed since those cold days in March of 1896 (a mere 17 years after the invention of the incandescent light bulb), when a group representing a variety of organizations met at the

46、 headquarters of the American Society of Mechanical Engineers in New York City to develop a national code of rules for electrical construction and operation. This was not the first attempt to establish consistent rules for electrical installations, but it was the first national effort. The need for

47、standardization was becoming urgent; the number of electrical fires was increasing. By 1881, one insurer had reported electrical fires in 23 of the 65 insured textile mills in New England. The major problem was the lack of an authoritative, nationwide electrical installation stan-dard. As one of the

48、 early participants noted, “We were without standards and inspectors, while manufacturers were without experience and knowledge of real installation needs. The workmen frequently created the standards as they worked, and rarely did two men think and work alike.” By 1895, five electrical installation

49、 codes were in use in the United States. The manufacture of products that met the requirements of all five codes was difficult, so something had to be done to develop a single national code. The committee that met in 1896 recognized that the five existing codes should be used collectively as the basis for the new code. In the first known instance of international harmonization, the group also referred to the German code, the code of the British Board of Trade, and the Phoenix Rules of England. The importance of industry consensus was immediately recognized; before t