NFPA 70H-2014 en National Electrical Code Handbook (Thirteenth Edition).pdf

1、NFPA70 National Electrical Code 2014 Edition NFPA, 1 Batterymarch Park, Quincy, MA 02169-7471 An International Codes and Standards Organization Copyrighted material licensed to Stanford University by Thomson Reuters (Scientific), Inc., , downloaded on Feb-17-2014 by Stanford University User. No furt

2、her reproduction or distribution is permitted. Uncontrolled when printed.7 /13Copyright 2013National Fire Protection AssociationOne Batterymarch Park Quincy, Massachusetts 02169-7471NFPA, NFPA 70, National Fire Protection Association, National Electrical Code, and NEC are registered trademarks of th

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14、ation are posted regarding the document. ISBN: 978-145590672-7 (SB Print)ISBN: 978-145590671-0 (LL Print)ISBN: 978-145590673-4 (Spiral Print)ISBN: 978-145590680-2 (PDF)Copyrighted material licensed to Stanford University by Thomson Reuters (Scientific), Inc., , downloaded on Feb-17-2014 by Stanford

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31、n about NFPA, visit the NFPA website at www.nfpa.org.12/12Copyrighted material licensed to Stanford University by Thomson Reuters (Scientific), Inc., , downloaded on Feb-17-2014 by Stanford University User. No further reproduction or distribution is permitted. Uncontrolled when printed.CommitteeChic

32、ago,21,ForGoverningTIAErrataFI/TIARegs.pdf.191insurance,NationalNationalvariousonofandCode-Makingmittee.whichcommentCommitteepresentedelectricalElectricalReviewdiscussedition1899,1930,1958,2005,bothandinsurancecertification.NFPA 70, National ElectricalCopyrighted material licensed to Stanford Univer

33、sity by Thomson Reuters (Scientific), Inc., , downloaded on Feb-17-2014 by Stanford University User. No further reproduction or distribution is permitted. Uncontrolled when printed.Copyright 2013, National Fire Protection Association. All Rights ReservedNFPA 70National Electrical Code2014 EditionThi

34、s edition of NFPA 70, National Electrical Code, was prepared by the National Electrical Codeand acted on by NFPA at its June Association Technical Meeting held June 1013, 2013, inIL. It was issued by the Standards Council on August 1, 2013, with an effective date of August2013, and supersedes all pr

35、evious editions.A tentative interim amendment (TIA) to Sections 516.3 and 516.10 was issued on August 1, 2013.further information on tentative interim amendments, see Section 5 of the NFPA RegulationsCommittee Projects available at: http:/www.nfpa.org/assets/files/PDF/CodesStandards/This edition of

36、NFPA 70 was approved as an American National Standard on August 21, 2013.History and Development of the National Electrical CodeThe National Fire Protection Association has acted as sponsor of the National Electrical Code since1. The original Code document was developed in 1897 as a result of the un

37、ited efforts of variouselectrical, architectural, and allied interests.In accordance with the provisions of the NFPA Regulations Governing Committee Projects, aElectrical Code Committee Report on Proposals containing proposed amendments to the 2011Electrical Code was published by NFPA in July 2012.

38、This report recorded the actions of theCode-Making Panels and the Correlating Committee of the National Electrical Code Committeeeach proposal that had been made to revise the 2011 Code. The report was circulated to all membersthe National Electrical Code Committee and was made available to other in

39、terested NFPA membersto the public for review and comment. Following the close of the public comment period, thePanels met, acted on each comment, and reported their action to the Correlating Com-NFPA published the National Electrical Code Committee Report on Comments in March 2013,recorded the acti

40、ons of the Code-Making Panels and the Correlating Committee on each publicto the National Electrical Code Committee Report on Proposals. The National Electrical CodeReport on Proposals and the National Electrical Code Committee Report on Comments wereto the 2013 June Association Technical Meeting fo

41、r adoption.NFPA has an Electrical Section that provides particular opportunity for NFPA members interested insafety to become better informed and to contribute to the development of the NationalCode and other NFPA electrical standards. At the Electrical Section Codes and StandardsSession held at the

42、 2013 NFPA Conference and Expo, Section members had opportunity toand review the report of the National Electrical Code Committee prior to the adoption of thisof the Code by the Association at its 2013 June Technical Session.This 53rd edition supersedes all other previous editions, supplements, and

43、printings dated 1897,1901, 1903, 1904, 1905, 1907, 1909, 1911, 1913, 1915, 1918, 1920, 1923, 1925, 1926, 1928,1931, 1933, 1935, 1937, 1940, 1942, 1943, 1947, 1949, 1951, 1953, 1954, 1955, 1956, 1957,1959, 1962, 1965, 1968, 1971, 1975, 1978, 1981, 1984, 1987, 1990, 1993, 1996, 1999, 2002,2008, and 20

44、11.This Code is purely advisory as far as NFPA is concerned. It is made available for a wide variety ofpublic and private uses in the interest of life and property protection. These include both use in lawfor regulatory purposes, and use in private self-regulation and standardization activities such

45、 asunderwriting, building and facilities construction and management, and product testing andCode, NFPA, and National Fire Protection Association are registered trademarks of the National Fire Protection Association, Quincy, Massachusetts, 02169.II. Location 7098III. Enclosures . 70101Bodies, and Ha

46、ndhole Enclosures forUse on Systems over 1000 Volts,CONTENTSCopyrighted material licensed to Stanford University by Thomson Reuters (Scientific), Inc., , downloaded on Feb-17-2014 by Stanford University User. No further reproduction or distribution is permitted. Uncontrolled when printed.Contents90

47、Introduction 7023Chapter 1 General100 Definitions . 7027I. General . 7027II. Over 600 Volts, Nominal . 7035110 Requirements for Electrical Installations . 7036I. General . 7036II. 600 Volts, Nominal, or Less 7040III. Over 600 Volts, Nominal . 7042IV. Tunnel Installations over 600 Volts,Nominal . 704

48、6V. Manholes and Other ElectricalEnclosures Intended for PersonnelEntry, All Voltages 7047Chapter 2 Wiring and Protection200 Use and Identification of GroundedConductors 7049210 Branch Circuits . 7051I. General Provisions . 7051II. Branch-Circuit Ratings 7057III. Required Outlets 7060215 Feeders . 7

49、064220 Branch-Circuit, Feeder, and ServiceCalculations 7066I. General . 7066II. Branch-Circuit Load Calculations . 7067III. Feeder and Service Load Calculations 7069IV. Optional Feeder and Service LoadCalculations 7073V. Farm Load Calculations . 7076225 Outside Branch Circuits and Feeders . 7076I. General . 7076II. Buildings or Other Structures Suppliedby a Feeder(s) or Branch Circuit(s) 7079III. Over 1000 Vo