1、IEEE Std 303-2004(Revision ofIEEE Std 303-1991)IEEE Standards303TMIEEE Recommended Practice forAuxiliary Devices for RotatingElectrical Machines in Class I,Division 2 and Zone 2 Locations3 Park Avenue, New York, NY 10016-5997, USAIEEE Industry Applications Society Sponsored by thePetroleum and Chemi
2、cal Industry CommitteeIEEE Standards17 December 2004Print: SH95243PDF: SS95243IEEE Std 303-2004(R2011) (Revision of IEEE Std 303-1991) IEEE Recommended Practice for Auxiliary Devices for Rotating Electrical Machines in Class I, Division 2 and Zone 2 Locations Sponsor Petroleum and Chemical Industry
3、Committee of the Industry Applications Society Approved 24 June 2004 Reaffirmed 7 December 2011 IEEE-SA Standards Board Abstract: This recommended practice applies to the application and installation procedures of auxiliary devices in or on electric rotating machines that are employed in hazardous l
4、ocations classified as Class I, Division 2 or Class I Zone 2 under commonly used worldwide regulations. These regulations are: the National Electrical Code (United States); the Canadian Electrical Code, Part 1 (Canada); and combined practices of the International Electrotechnical Commission (IEC),th
5、e European Committee for Electrotechnical Standardization (CENELEC), and Standards Australia / Standards New Zealand (AS/NZS). Included is a list of source documents, definitions and nomenclature. Devices include terminal housings, heaters, surge protection, power factor correction capacitors, shaft
6、 grounding, and enclosures. Special marking requirements are also discussed. Keywords: auxiliary devices, Class I Division 2, Class I Zone 2, arcing/sparking component, rotating electrical machine The Institute of Electrical and Electronics Engineers, Inc. 3 Park Avenue, New York, NY 10016-5997, USA
7、 Copyright 2004 by the Institute of Electrical and Electronics Engineers, Inc. All rights reserved. Published 17 December 2004. Printed in the United States of America. IEEE is a registered trademark in the U.S. Patent +1 978 750 8400. Permission to photocopy portions of any individual standard for
8、educational classroom use can also be obtained through the Copyright Clearance Center. Copyright 2004 IEEE. All rights reserved. iiiIntroductionThis standard was originally published in 1969, revised in 1984 and reaffirmed in 1991. In keeping with thegoals of maintaining progressive standards, in 20
9、00 the standards group of the IEEE Petroleum andChemical Industry Committee assigned a task force to revise and update this standard. References to otherdocumentation were corrected. The wording in this standard was modified to reflect worldwide standardsand to promote uniform application of such de
10、vices in petroleum and chemical industry facilities.Notice to usersErrataErrata, if any, for this and all other standards can be accessed at the following URL: http:/standards.ieee.org/reading/ieee/updates/errata/index.html. Users are encouraged to check this URL forerrata periodically.Interpretatio
11、nsCurrent interpretations can be accessed at the following URL: http:/standards.ieee.org/reading/ieee/interp/index.html.PatentsAttention is called to the possibility that implementation of this standard may require use of subject mattercovered by patent rights. By publication of this standard, no po
12、sition is taken with respect to the existence orvalidity of any patent rights in connection therewith. The IEEE shall not be responsible for identifyingpatents or patent applications for which a license may be required to implement an IEEE standard or forconducting inquiries into the legal validity
13、or scope of those patents that are brought to its attention.This introduction is not part of IEEE Std 303-2004, IEEE Recommended Practice for Auxiliary Devices for Rotating Electrical Machines in Class I, Division 2 and Zone 2 Locations.iv Copyright 2004 IEEE. All rights reserved.ParticipantsAt the
14、time this standard was completed, the working group had the following membership: Travis Griffith, Chair and SecretaryRichard H. Hulett, PCIC Standards LiaisonThe following members of the individual, entity, or individual and entity balloting committee voted on thisstandard. Balloters may have voted
15、 for approval, disapproval, or abstention. When the IEEE-SA Standards Board approved this standard on 24 June 2004, it had the followingmembership:Don Wright, ChairSteve M. Mills, Vice ChairJudith Gorman, Secretary*Member EmeritusAlso included are the following nonvoting IEEE-SA Standards Board liai
16、sons:Satish K. Aggarwal, NRC RepresentativeRichard DeBlasio, DOE RepresentativeAlan Cookson, NIST RepresentativeMichael D. FisherIEEE Standards Project EditorPaul AndersonFrederick BriedMichael CostelloGabriele DAllevaRichard L. DoughtyJames DymondCarl J. FredericksDavid HulfordPaul KellyBob KeoughR
17、oyce M.KingNorbert KlekowskiWilliam LockleyJohn MalinowskiDaleep C. MohlaRaymond OngJohn C. RamaScott W. ShannonRudi StromerMichael ToneyRichard VirgillioDennis VossDavid WaddingtonBarry M. WoodPaul AndersonKeith ChowRoger DaughertyGary DonnerDonald DunnJames DymondKimberly EastwoodAmir El-SheikhCar
18、l FredericksJohn GriffithRichard HulettRobert J. KeoughRoyce M. KingBill LockleyJohn MalinowskiDaleep MohlaPaul MyersArt NeubauerFunso OlorunyomiLorraine PaddenJohn PropstJames RuggieriChet SandbergRobert SeitzJames WilsonBarry WoodChuck AdamsH. Stephen BergerMark D. BowmanJoseph A. BruderBob DavisR
19、oberto de BoissonJulian Forster*Arnold M. GreenspanMark S. HalpinRaymond HapemanRichard J. HollemanRichard H. HulettLowell G. JohnsonJoseph L. Koepfinger*Hermann KochThomas J. McGeanDaleep C. MohlaPaul NikolichT. W. OlsenRonald C. PetersenGary S. RobinsonFrank StoneMalcolm V. ThadenDoug ToppingJoe D
20、. WatsonCopyright 2004 IEEE. All rights reserved. vContents1. Overview 11.1 Scope 11.2 Purpose. 12. References 13. Definitions and acronyms 53.1 Definitions . 53.2 Acronyms. 84. Auxiliary device categories . 94.1 Protection devices containing an arcing/sparking component and/or a make-and-break cont
21、act.94.2 Protection devices without an arcing/sparking component or a make-and-break contact 105. Wiring methods and materials . 115.1 NFPA requirements . 115.2 Canadian requirements 116. Device and component installation recommendations 116.1 Terminal housings 116.2 Space heaters 126.3 Bearing oil
22、heaters . 146.4 Surge Protection. 156.5 Power Factor Correction Capacitors 156.6 Shaft grounding 157. Enclosures 167.1 Multi-sectioned requirements 167.2 Purging or pressurizing components 168. Marking 168.1 CSA requirements. 16Copyright 2004 IEEE. All rights reserved. 1IEEE Recommended Practice for
23、 Auxiliary Devices for Rotating Electrical Machines in Class I, Division 2 and Zone 2 Locations1. Overview1.1 ScopeThis recommended practice is limited to auxiliary devices associated with rotating electrical machinesoperating in Division 2 or Zone 2 areas, classified as Class I under the practice o
24、f NFPA 70-2005, NationalElectrical Code(NEC),1,2CSA C22.1-02,3or Zone 2 areas classified under the practice of IEC 60079-10-20024and CENELEC EN 60079-10-1996.5This recommended practice is not an attempt to rewrite orotherwise supersede applicable sections or clauses of these noted documents or any o
25、ther codes orordinances. Rather, it is intended to serve as a supplement to existing codes that in this area may not besufficiently specific to serve as a guide to good engineering practice.1.2 PurposeThe following information is intended to bring together a brief description of basic electrical pra
26、ctices withregard to the application and installation of auxiliary devices to rotating electrical machines operating inClass I, Division 2 or Zone 2 locations using NFPA 70-2005, National Electrical Code, CSA C22.1-02, orZone 2 locations using IEC 60079-14-2002 and CENELEC EN 60079-14-1997. It shoul
27、d be understood thatthis information is only a recommended practice to promote consistent application of such devices and mustbe used with sound engineering judgment.2. ReferencesThis recommended practice shall be used in conjunction with the following publications. When thefollowing standards are s
28、uperseded by an approved revision, the revision shall apply.API RP 500-1997, Recommended Practice for Classification of Locations for Electrical Installations atPetroleum Facilities Classified as Class I, Division 1 and Division 2.61NFPA publications are available from Publications Sales, National F
29、ire Protection Association, 1 Batterymarch Park, P.O. Box 9101, Quincy, MA 02269-9101, USA (http:/www.nfpa.org/).2National Electric Code and NEC are both registered trademarks of the National Fire Protection Association, Inc.3CSA publications are available from the Canadian Standards Association, 50
30、60 Spectrum Way, Mississauga, Ontario L4W 5N6, Canada (http:/www.csa.ca/standards/).4IEC publications are available from the IEC Central Office, 3, rue de Varemb, P.O. Box 131, Switzerland (http:/www.iec.ch/).5CENELEC publications are available from the Cenelec CS Info or 2) in which ignitableconcen
31、trations of gases or vapors are normally prevented by positive mechanical ventilation, and whichmight become hazardous through failure or abnormal operation of the ventilating equipment; or 3) that isadjacent to a Class I, Division 1 location, and to which ignitable concentration of gases or vapors
32、mightoccasionally be communicated unless such communication is prevented by adequate positive pressure venti-lation from a source of clean air and effective safeguards against ventilation failure are provided. NOTERefer to the latest edition of NFPA 70-2005, Chapter 5, Articles 500 and 505. For a gu
33、ide in establishing thelimits of these locations, refer to API RP 500-1997; API RP 505-1997; and NFPA 497-2004.103.1.3 Class I, Zone 2:Locations in which:a) Explosive gas atmospheres are not likely to occur in normal operation and, if they do occur, theywill exist for a short time only; orb) Flammab
34、le volatile liquids, flammable gases, or vapors are handled, processed, or used, but inwhich liquids, gases, or vapors are normally confined within closed containers or closed systemsfrom which they can escape only as a result of accidental rupture or breakdown of the containers orsystems or the abn
35、ormal operation of the equipment by which the liquids or gases are handled, pro-cessed or used; orc) Explosive gas atmospheres are normally prevented by adequate ventilation but may occur as a resultof failure or abnormal operation of the ventilation system; or9IEEE publications are available from t
36、he Institute of Electrical and Electronics Engineers, Inc., 445 Hoes Lane, Piscataway, NJ 08854, USA (http:/standards.ieee.org/).10Notes in text, tables, and figures are given for information only, and do not contain requirements needed to implement the standard.IEEEStd 303-2004 IEEE RECOMMENDED PRA
37、CTICE FOR AUXILIARY DEVICES FOR ROTATING6 Copyright 2004 IEEE. All rights reserved.d) The location is adjacent to a Class I, Zone 1 location from which explosive gas atmospheres couldbe communicated, unless such communication is prevented by adequate positive-pressure ventila-tion from a source of c
38、lean air, and effective safeguards against ventilation failure are provided.NOTERefer to the latest edition of CSA C22.1 02 Section 18. For a guide in establishing the limits of these locations,refer to API RP 500-1997; API RP 505-1997; and NFPA 497-2004.3.1.4 classified area: Also referred to as ha
39、zardous (classified) area. (See: hazardous area).3.1.5 explosion-proof enclosure: An enclosure designed and constructed to withstand an explosion of aspecified flammable gas or vapor that may occur within it, and to prevent the ignition of flammable gas orvapor in the atmosphere surrounding the encl
40、osure by sparks, flashes, or explosions of the specified gas orvapor that may occur within the enclosure.3.1.6 flameproof enclosure: Flameproof enclosure “d”: An enclosure in which the parts which can ignite anexplosive atmosphere are placed and which can withstand the pressure developed during an i
41、nternalexplosion of an explosive mixture, and which prevents the transmission of the explosion to the explosiveatmosphere surrounding the enclosure. NOTERefer to AS/NZS 60079.1-2002; CENELEC EN 50018-2000; CAN/CSA-E60079-1:02; IEC 60079-1:2001;and UL 60079-1 -2002.3.1.7 flammability classification:
42、Flammable gases or vapors of flammable liquids are segregated intogroups by the degree of severity relevant to the flame transmission characteristics and explosion pressure ofgases or vapors within that group. For the respective area classification methodologies, those groups are:Groups A, B, C, and
43、 DFour groups defined as:A Atmospheres containing acetyleneB Atmospheres containing hydrogen fuel and process gas containing 30% hydrogen or gassesof equivalent hazard (butadiene, ethylene oxide, propylene oxide, acrolein, etc.)C Atmospheres such as ethyl ether, ethylene or gasses of equivalent haza
44、rdD Atmospheres such as acetone, ammonia, benzene, butane, cyclopropane, ethanol, gasoline,hexane, methanol, natural gas, naptha, propane, or gasses of equivalent hazard.NOTERefer to NFPA 497-2004.Groups IIC, IIB, and IIAThree groups defined as:IIC Atmospheres containing acetylene, hydrogen or gasse
45、s of equivalent hazardIIB Atmospheres containing acetaldehyde, ethylene, or gasses of equivalent hazardIIA Atmospheres containing acetone, ammonia, ethyl alcohol, gasoline, methane, propane, orgasses of equivalent hazard.NOTERefer to NFPA 70-2005, Section 505.6.Groups I, IIA, IIB, and IICFour groups
46、 defined as: I Mining applications (methane)IIA Maximum Experimental Safe Gap (MESG) greater than 0.9 mm or Minimum Igniting Current(MIC) ratio greater than 0.8IEEEELECTRICAL MACHINES IN CLASS I, DIVISION 2 AND ZONE 2 LOCATIONS Std 303-2004Copyright 2004 IEEE. All rights reserved. 7IIB MESG greater
47、than 0.5 mm and less than or equal to 0.9 mm or MIC ratio greater than 0.45 andless than or equal to 0.8IIC MESG less than or equal to 0.5 mm or MIC ratio less than or equal to 0.45.NOTES1Refer to AS/NZS 60079.0:2000 Annex A; CENELEC EN 50014-1997 Annex A; or IEC 60079-0:2000 Annex A.2For most gasse
48、s and vapors it is sufficient to make only one determination of either MESG or MIC for classification.3.1.8 hazardous area: An area in which a gas or vapor is present, or may be expected to be present in quan-tities sufficient to produce explosive or ignitable mixtures, and which require appropriate
49、 precautions for thedesign, manufacturing, installation and operation of electrical apparatus.3.1.9 hermetically sealed: A device which is so constructed that the external atmosphere cannot gain accessto the interior and in which the seal is made by soldering, brazing, welding or the fusion of glass to metal.Under NFPA 70-2005, hermetically sealed devices are permitted for current-interrupting contacts. NOTESee also the sealed device requirements of CENELEC EN 50021-1999; CSA C22.2 No. 213-M1987 (R1999);CAN/CSA-E60079-15:02; IEC 60079-15:2001; UL 1604-199
