NFPA 70A-2005 National Electrical Code Requirements for One- and Two-Family Dwellings《单户和双户居室的国家电气规范》.pdf

1、NFPA 70A National Electrical CodeRequirements for One- and Two-Family Dwellings 2005 Edition NFPA, 1 Batterymarch Park, Quincy, MA 02169-7471 An International Codes and Standards Organization IMPORTANT NOTICES AND DISCLAIMERS CONCERNING NFPA DOCUMENTSNOTICE AND DISCLAIMER OF LIABILITY CONCERNING THE

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21、, addressed to the attention of the Secretary, Standards Council, NFPA,1 Batterymarch Park, P.O. Box 9101, Quincy, MA 02269-9101.For more information about NFPA, visit the NFPA website at www.nfpa.org.70AiCopyright H17015 2005 NFPA, All Rights ReservedNFPA 70ANational Electrical CodeH23041 Requireme

22、nts for One- and Two-Family Dwellings2005 EditionExcerpted from the 2005 National Electrical CodeH23041 NFPA 702005PrefaceThis 2005 edition of NFPA 70A is a compilation of electrical provisions for one- and two-family dwellings. The provisions assembled in this compilation have been extracted direct

23、ly fromthe 2005 edition of NFPA 70, National Electrical CodeH23041 (NECH23041), and have been editorially revisedonly where necessary to limit their application to one- and two-family dwellings. This compilationhas been reviewed and approved by the National Electrical Code Committee through its Tech

24、nicalCorrelating Committee. It is being provided for the convenience of inspectors, contractors, builders,and others who are primarily interested in only those NEC rules that apply to one- and two-familydwellings.Only those wiring methods and materials commonly encountered in new construction at one

25、-and two-family dwellings are included in NFPA 70A. In like manner, only current ratings up toand including 400 amperes (based on Table 310.15(B)(6) and voltages up to and including 600volts are covered in NFPA 70A. It is the intent that the rules covering wiring methods, any materials,or any type o

26、f equipment, such as motors, not specifically included in this document are to becovered by the applicable rules in the 2005 edition of the National Electrical Code.Where a reference is made to an article or section not included in NFPA 70A, such as toArticle 430 or 430.52, the reference is to that

27、article or section as it appears in the 2005 editionof the National Electrical Code.The numbering system for articles and sections of the 2005 edition of the National ElectricalCode has been preserved in NFPA 70A, so that provisions in NFPA 70A bear the same numericaldesignation as they have in the

28、NEC. The user of NFPA 70A should be aware, therefore, that thereare gaps in the numerical sequence of provisions in NFPA 70A, and that these gaps are a naturalconsequence of the fact that NFPA 70A contains only selected provisions of the NEC.This edition of NFPA 70A has been reviewed by the NEC Tech

29、nical Correlating Committee,and the committee has determined, by way of an affirmative letter ballot, that the extracting andeditorial revision of NEC text included in NFPA 70A has been achieved without altering thetechnical intent of the 2005 edition of the National Electrical Code.As the 2005 edit

30、ion of the National Electrical Code is the parent document for the extractedtext contained in NFPA 70A, any request for a formal interpretation of any text in NFPA 70A willbe processed in accordance with the NFPA Regulations Governing Committee Projects as a formalinterpretation of the 2005 edition

31、of the National Electrical Code.Prior to this 2005 edition, the most recent previous edition of NFPA 70A was the 2002edition.NFPA 70A NATIONAL ELECTRICAL CODEH23041 REQUIREMENTS FOR ONE- AND TWO-FAMILY DWELLINGS 2005 Edition70Aii NATIONAL ELECTRICAL CODE COMMITTEENATIONAL ELECTRICAL CODE COMMITTEETh

32、is list represents the membership at the time the Technical Correlating Committee was balloted on the final text of thisedition. Since that time, changes in the membership may have occurred. A key to classifications is found at the back of thisbook.Technical Correlating CommitteeJames W. Carpenter,

33、Chair EInternational Association of Electrical Inspectors, TXRep. International Association of Electrical InspectorsMark W. Earley, SecretaryNational Fire Protection Association, MA(nonvoting)Jean A. OConnor, Recording SecretaryNational Fire Protection Association, MA(nonvoting)James E. Brunssen, Te

34、lcordia, NJ UT Rep. National Electrical Manufacturers Association(Alt. to J. T. Pauley)Rep. Alliance for Telecommunications Industry SolutionsMichael I. Callanan, National Joint Apprentice ConduitI. General 70A26Bodies; Fittings; and Handhole Enclosures .70A76II. Branch Circuit Load Calculations 70A

35、26I. Scope and General 70A76III. Feeder and Service Load Calculations.70A27II. Installation70A76225 Outside Branch Circuits and Feeders .70A30320 Armored Cable: Type AC .70A82I. General 70A31I. General 70A82II. More Than One Building or OtherII. Installation70A82Structure .70A33330 Metal-Clad Cable:

36、 Type MC .70A83230 Services .70A34I. General 70A83I. General 70A34II. Installation70A83II. Overhead Service-Drop Conductors 70A35334 Nonmetallic-Sheathed Cable: Types NM andIII. Underground Service-LateralNMC.70A84Conductors .70A36I. General 70A84IV. Service-Entrance Conductors .70A37II. Installatio

37、n70A84V. Service EquipmentGeneral .70A39VI. Service EquipmentDisconnecting338 Service-Entrance Cable: Types SE and USE 70A86Means.70A39I. General 70A86VII. Service EquipmentOvercurrentII. Installation70A86Protection 70A40340 Underground Feeder and Branch-Circuit Cable:240 Overcurrent Protection .70A

38、41TypeUF.70A87I. General 70A41I. General 70A87II. Location .70A42II. Installation70A87III. Enclosures 70A43342 Intermediate Metal Conduit: Type IMC .70A87V. Plug Fuses, Fuseholders, and Adapters 70A43I. General 70A87250 Grounding and Bonding 70A43II. Installation70A88I. General 70A43344 Rigid Metal

39、Conduit: Type RMC 70A89II. System Grounding 70A45III. Grounding Electrode System and Grounding I. General 70A89II. Installation70A89Electrode Conductor .70A47NFPA 70A NATIONAL ELECTRICAL CODEH23041 REQUIREMENTS FOR ONE- AND TWO-FAMILY DWELLINGS 2005 Edition70Aiv CONTENTSARTICLE ARTICLE348 Flexible M

40、etal Conduit: Type FMC 70A90 411 Lighting Systems Operating at 30 Volts orLess .70A113I. General 70A90II. Installation70A91422 Appliances 70A113350 Liquidtight Flexible Metal Conduit: TypeI. General .70A113LFMC 70A92II. Installation.70A114I. General 70A92III. Disconnecting Means .70A116II. Installat

41、ion70A92V. Marking 70A116352 Rigid Nonmetallic Conduit: Type RNC70A93424 Fixed Electric Space-Heating Equipment .70A117I. General 70A93I. General .70A117II. Installation70A93II. Installation.70A117356 Liquidtight Flexible Nonmetallic Conduit: TypeIII. Control and Protection of Fixed ElectricLFNC.70A

42、95Space-Heating Equipment 70A118I. General 70A95IV. Marking of Heating Equipment 70A119II. Installation70A96V. Electric Space-Heating Cables .70A120VI. Duct Heaters .70A121358 Electrical Metallic Tubing: Type EMT 70A97VII. Resistance-Type Boilers .70A122I. General 70A97IX. Electric Radiant Heating P

43、anels andII. Installation70A97Heating Panel Sets .70A122362 Electrical Nonmetallic Tubing: Type ENT70A99440 Air-Conditioning and RefrigeratingI. General 70A99Equipment.70A124II. Installation70A99I. General .70A124380 Multioutlet Assembly .70A100II. Disconnecting Means .70A125III. Branch-Circuit Shor

44、t-Circuit andChapter 4 Equipment for General UseGround-Fault Protection .70A126IV. Branch-Circuit Conductors70A127400 Flexible Cords and Cables .70A101V. Controllers for Motor-Compressors70A127I. General .70A101VI. Motor-Compressor and Branch-Circuit404 Switches 70A101Overload Protection 70A128VII.

45、Provisions for Room Air Conditioners . . . 70A129I. Installation.70A101406 Receptacles, Cord Connectors, and Attachment445 Generators.70A129Plugs (Caps) .70A103408 Switchboards and Panelboards.70A105Chapter 5 Special OccupanciesI. General .70A105III. Panelboards 70A106 550 Mobile Homes, Manufactured

46、 Homes, andMobile Home Parks 70A131410 Luminaires (Lighting Fixtures), Lampholders,I. General .70A131and Lamps 70A107III. Services and Feeders70A131I. General .70A107II. Luminaire (Fixture) Locations .70A107590 Temporary Installations70A133III. Provisions at Luminaire (Fixture) OutletBoxes, Canopies

47、, and Pans .70A108IV. Luminaire (Fixture) Supports 70A109Chapter 6 Special EquipmentV. Grounding .70A109VI. Wiring of Luminaires (Fixtures) 70A110 680 Swimming Pools, Fountains, and SimilarVIII. Installation of Lampholders .70A111 Installations70A137XI. Special Provisions for Flush and RecessedI. Ge

48、neral .70A137Luminaires (Fixtures) .70A111II. Permanently Installed Pools .70A139XIII. Special Provisions for Electric-DischargeIII. Storable Pools 70A146Lighting Systems of 1000 Volts orIV. Spas and Hot Tubs .70A147Less .70A111VII. Hydromassage Bathtubs .70A148XIV. Special Provisions for Electric-D

49、ischargeLighting Systems of More Than 1000 690 Solar Photovoltaic Systems .70A149Volts .70A112XV. Lighting Track 70A112 692 Fuel Cell Systems .70A149NFPA 70A NATIONAL ELECTRICAL CODEH23041 REQUIREMENTS FOR ONE- AND TWO-FAMILY DWELLINGS2005 Edition70AvCONTENTSARTICLE ARTICLEII. Cables Outside and Entering Buildings . . . 70A163Chapter 7 Special ConditionsIII. Protection .70A164702 Optional Standby Systems70A151IV. Grounding Methods 70A164I. General .70A1