IEC TR 60269-5-2014 Low-voltage fuses - Part 5 Guidance for the application of low-voltage fuses《低压熔断器 第5部分 低压熔断器应用指南》.pdf

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1、 IEC TR 60269-5 Edition 2.0 2014-03 TECHNICAL REPORT RAPPORT TECHNIQUE Low-voltage fuses Part 5: Guidance for the application of low-voltage fuses Fusibles basse tension Partie 5: Lignes directrices pour lapplication des fusibles basse tension IEC TR 60269-5:2014-03(en-fr) colour inside THIS PUBLICA

2、TION IS COPYRIGHT PROTECTED Copyright 2014 IEC, Geneva, Switzerland All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing fr

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5、IEC du pays du demandeur. Si vous avez des questions sur le copyright de lIEC ou si vous dsirez obtenir des droits supplmentaires sur cette publication, utilisez les coordonnes ci-aprs ou contactez le Comit national de lIEC de votre pays de rsidence. IEC Central Office Tel.: +41 22 919 02 11 3, rue

6、de Varemb Fax: +41 22 919 03 00 CH-1211 Geneva 20 infoiec.ch Switzerland www.iec.ch About the IEC The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes International Standards for all electrical, electronic and related technologies. About

7、IEC publications The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the latest edition, a corrigenda or an amendment might have been published. IEC Catalogue - webstore.iec.ch/catalogue The stand-alone application for consulting the ent

8、ire bibliographical information on IEC International Standards, Technical Specifications, Technical Reports and other documents. Available for PC, Mac OS, Android Tablets and iPad. IEC publications search - www.iec.ch/searchpub The advanced search enables to find IEC publications by a variety of cri

9、teria (reference number, text, technical committee,). It also gives information on projects, replaced and withdrawn publications. IEC Just Published - webstore.iec.ch/justpublished Stay up to date on all new IEC publications. Just Published details all new publications released. Available online and

10、 also once a month by email. Electropedia - www.electropedia.org The worlds leading online dictionary of electronic and electrical terms containing more than 30 000 terms and definitions in English and French, with equivalent terms in 14 additional languages. Also known as the International Electrot

11、echnical Vocabulary (IEV) online. IEC Glossary - std.iec.ch/glossary More than 55 000 electrotechnical terminology entries in English and French extracted from the Terms and Definitions clause of IEC publications issued since 2002. Some entries have been collected from earlier publications of IEC TC

12、 37, 77, 86 and CISPR. IEC Customer Service Centre - webstore.iec.ch/csc If you wish to give us your feedback on this publication or need further assistance, please contact the Customer Service Centre: csciec.ch. A propos de lIEC La Commission Electrotechnique Internationale (IEC) est la premire org

13、anisation mondiale qui labore et publie des Normes internationales pour tout ce qui a trait llectricit, llectronique et aux technologies apparentes. A propos des publications IEC Le contenu technique des publications IEC est constamment revu. Veuillez vous assurer que vous possdez ldition la plus rc

14、ente, un corrigendum ou amendement peut avoir t publi. Catalogue IEC - webstore.iec.ch/catalogue Application autonome pour consulter tous les renseignements bibliographiques sur les Normes internationales, Spcifications techniques, Rapports techniques et autres documents de lIEC. Disponible pour PC,

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16、 ou retires. IEC Just Published - webstore.iec.ch/justpublished Restez inform sur les nouvelles publications IEC. Just Published dtaille les nouvelles publications parues. Disponible en ligne et aussi une fois par mois par email. Electropedia - www.electropedia.org Le premier dictionnaire en ligne d

17、e termes lectroniques et lectriques. Il contient plus de 30 000 termes et dfinitions en anglais et en franais, ainsi que les termes quivalents dans 14 langues additionnelles. Egalement appel Vocabulaire Electrotechnique International (IEV) en ligne. Glossaire IEC - std.iec.ch/glossary Plus de 55 000

18、 entres terminologiques lectrotechniques, en anglais et en franais, extraites des articles Termes et Dfinitions des publications IEC parues depuis 2002. Plus certaines entres antrieures extraites des publications des CE 37, 77, 86 et CISPR de lIEC. Service Clients - webstore.iec.ch/csc Si vous dsire

19、z nous donner des commentaires sur cette publication ou si vous avez des questions contactez-nous: csciec.ch. IEC TR 60269-5 Edition 2.0 2014-03 TECHNICAL REPORT RAPPORT TECHNIQUE Low-voltage fuses Part 5: Guidance for the application of low-voltage fuses Fusibles basse tension Partie 5: Lignes dire

20、ctrices pour lapplication des fusibles basse tension INTERNATIONAL ELECTROTECHNICAL COMMISSION COMMISSION ELECTROTECHNIQUE INTERNATIONALE XA ICS 29.120.50 PRICE CODE CODE PRIX ISBN 978-2-8322-1448-0 Registered trademark of the International Electrotechnical Commission Marque dpose de la Commission E

21、lectrotechnique Internationale Warning! Make sure that you obtained this publication from an authorized distributor. Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agr. colour inside 2 IEC TR 60269-5:2014 IEC 2014 CONTENTS FOREWORD . 6 INTRODUCTION . 8 1

22、Scope 9 2 Normative references 9 3 Terms and definitions 10 4 Fuse benefits . 12 5 Fuse construction and operation 13 5.1 Components . 13 5.2 Fuse-construction . 13 5.2.1 Fuse link 13 5.2.2 Fuse-link contacts . 14 5.2.3 Indicating device and striker 14 5.2.4 Fuse-base . 14 5.2.5 Replacement handles

23、and fuse-holders . 14 5.3 Fuse operation 15 5.3.1 General . 15 5.3.2 Fuse operation in case of short-circuit . 15 5.3.3 Fuse operation in case of overload 15 5.3.4 Fuse link pre-arcing time current characteristic: . 16 5.3.5 Fuse operation in altitudes exceeding 2 000 m 17 6 Fuse-combination units 1

24、8 7 Fuse selection and markings . 19 8 Conductor protection . 21 8.1 General . 21 8.2 Utilization category gG . 22 8.3 Utilization category gN and gD 23 8.4 Utilization category gR and gS 23 8.5 Utilization category gU 24 8.6 Utilization category gK 24 8.7 Utilization category gPV 24 8.8 Protection

25、against short-circuit current only 24 9 Selectivity of protective devices . 24 9.1 General . 24 9.2 Selectivity between fuses 25 9.2.1 General . 25 9.2.2 Verification of selectivity for operating time 0,1 s 25 9.2.3 Verification of selectivity for operating time 0,1 s 26 9.2.4 Verification of total

26、selectivity 26 9.3 Selectivity of circuit-breakers upstream of fuses . 26 9.3.1 General . 26 9.3.2 Verification of selectivity for operating time 0,1 s 27 9.3.3 Verification of selectivity for operating time 0,1 s 27 9.3.4 Verification of total selectivity 27 9.4 Selectivity of fuses upstream of cir

27、cuit-breakers . 28 9.4.1 General . 28 9.4.2 Verification of selectivity for operating time 0,1 s 28 IEC TR 60269-5:2014 IEC 2014 3 9.4.3 Verification of selectivity for operating time 0,1 s 28 9.4.4 Verification of total selectivity 28 10 Short-circuit damage protection . 30 10.1 General . 30 10.2 S

28、hort-circuit current paths . 30 10.3 Current limitation 31 10.4 Rated conditional short-circuit current, rated breaking capacity . 31 11 Protection of power factor correction capacitors 31 12 Transformer protection 32 12.1 Distribution transformers with a high-voltage primary 32 12.2 Distribution tr

29、ansformers with a low-voltage primary . 33 12.3 Control circuit transformers . 33 13 Motor circuit protection 33 13.1 General . 33 13.2 Fuse and motor-starter coordination . 34 13.3 Criteria for coordination at the rated conditional short-circuit current I q. 34 13.4 Criteria for coordination at the

30、 crossover current I co. 35 13.5 Criteria for coordination at test current “r” . 35 14 Circuit-breaker protection in a.c. and d.c rated voltage circuits . 36 15 Protection of semiconductor devices in a.c. and d.c. rated voltage circuits 36 16 Fuses in enclosures . 38 16.1 General . 38 16.2 Limiting

31、temperature of utilization category gG fuse-links according to IEC 60269-2 System A . 38 16.3 Other fuse-links 38 17 DC applications . 38 17.1 General . 38 17.2 Short-circuit protection 38 17.3 Overload protection 39 17.4 Time-current characteristics 40 18 Automatic disconnection for protection agai

32、nst electric shock for installations in buildings 40 18.1 General . 40 18.2 Principle of the protection . 41 18.3 Examples 42 19 Photovoltaic (PV) system protection 43 19.1 General . 43 19.2 Selection of PV fuse-links . 44 19.2.1 Fuse utilization category 44 19.2.2 PV string fuses 44 19.2.3 Fuse rep

33、lacement 44 19.2.4 Unearthed or Ungrounded PV Systems 44 19.2.5 Functional earthing fuses . 44 19.2.6 PV array and PV sub-array fuses . 45 19.2.7 Fuse monitoring . 45 19.2.8 Breaking capacity 45 19.2.9 Voltage of gPV fuses . 45 19.2.10 Rated current of gPV fuses 45 4 IEC TR 60269-5:2014 IEC 2014 20

34、Protection of wind mills 45 Annex A (informative) Coordination between fuses and contactors/motor-starters 47 A.1 General . 47 A.2 Examples of suitable fuse-links used for motor protection . 47 A.3 Values of I 2 t and cut-off current observed in successful tests of fuse- link/motor-starter combinati

35、ons worldwide . 48 A.4 Criteria for coordination at the rated conditional short-circuit current I q. 51 A.4.1 General . 51 A.4.2 Maximum operating I 2 t and cut-off current . 51 A.4.3 Guidance for choosing the maximum rated current of an alternative fuse type . 52 A.4.4 Further guidance . 52 A.5 Cri

36、teria for coordination at test current “r“ . 53 A.6 Types of coordination 54 Bibliography 57 Figure 1 Typical fuse-link according to IEC 60269-2. 13 Figure 2 Typical fuse-link according to IEC 60269-2. 14 Figure 3 Current-limiting fuse operation . 15 Figure 4 Fuse operation on overload 16 Figure 5 T

37、ime current characteristic for fuse-links 17 Figure 6 Currents for fuse-link selection . 23 Figure 7 Selectivity General network diagram . 25 Figure 8 Verification of selectivity between fuses F 2and F 4for operating time t 0,1 s . 26 Figure 9 Verification of selectivity between circuit-breaker C 2a

38、nd fuses F 5and F 6. 27 Figure 10 Verification of selectivity between fuse F 2and circuit-breaker C 3for operating time t 0,1 s . 29 Figure 11 Verification of selectivity between fuse F 2and circuit-breaker C 3for operating time t 0,1 s . 30 Figure 12 Fuse and motor-starter coordination . 35 Figure

39、13 DC circuit . 39 Figure 14 DC breaking operation . 39 Figure 15 Fuse operating time at various d.c. circuit time constants . 40 Figure 16 Time-current characteristic . 42 Figure A.1 Collation of cut-off currents observed in successful coordination at I q. 49 Figure A.2 Pre-arcing and operating I 2

40、 t values of fuses used in successful coordination tests as a function of contactor rated current AC3 . 50 Figure A.3 Pre-arcing and operating I 2 t values of fuses used in successful coordination tests as a function of fuse rated current I n51 Figure A.4 Illustration of the method of selection of t

41、he maximum rated current of a fuse for back-up protection of a contactor of rating I e= X amperes . 54 Figure A.5 Withstand capabilities of a range of contactors and associated overload relays at test current “r“ 55 Figure A.6 Illustration of a method of deriving curves of maximum peak current at te

42、st current “r“ as a function of fuse rated current . 56 IEC TR 60269-5:2014 IEC 2014 5 Table 1 Derating factors for different altitudes 18 Table 2 Definitions and symbols of switches and fuse-combination units 19 Table 3 Fuse application 20 Table 4 Maximum operational voltage of a.c. fuse-links . 21

43、 Table 5 Typical operational voltage ratings of d.c. fuse-links 21 Table 6 Fuse selection for power factor correction capacitors (fuses according to IEC 60269-2, system A) 32 Table 7 Conventional non fusing current 37 Table 8 Time constants of typical d.c. circuits 40 Table A.1 Examples of typical f

44、use-link ratings used for motor-starter protection illustrating how the category of fuse-link can influence the optimum current rating 48 Table A.2 (Table 12 of IEC 60947-4-1:2009) Value of the prospective test current according to the rated operational current . 53 Table A.3 Types of coordination .

45、 54 6 IEC TR 60269-5:2014 IEC 2014 INTERNATIONAL ELECTROTECHNICAL COMMISSION _ LOW-VOLTAGE FUSES Part 5: Guidance for the application of low-voltage fuses FOREWORD 1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising all national electrote

46、chnical committees (IEC National Committees). The object of IEC is to promote international co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and in addition to other activities, IEC publishes International Standards, Technical Specificatio

47、ns, Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with may participate in this preparatory work. International,

48、governmental and non- governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for Standardization (ISO) in accordance with conditions determined by agreement between the two organizations. 2) The formal decis

49、ions or agreements of IEC on technical matters express, as nearly as possible, an international consensus of opinion on the relevant subjects since each technical committee has representation from all interested IEC National Committees. 3) IEC Publications have the form of recommendations for international use and are accepted by IEC National Committees in that sense. While

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