1、BSI Standards PublicationMeasuring relays and protection equipmentPart 149: Functional requirements for thermal electrical relaysBS EN 60255-149:2013National forewordThis British Standard is the UK implementation of EN 60255-149:2013. It isidentical to IEC 60255-149:2013. It superseeds BS EN 60255-8
2、:1998, whichis withdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee PEL/95, Measuring relays and protection systems.A list of organizations represented on this committee can be obtained onrequest to its secretary.This publication does not purport to include all the n
3、ecessary provisions ofa contract. Users are responsible for its correct application. The British Standards Institution 2013.Published by BSI Standards Limited 2013ISBN 978 0 580 74965 0ICS 29.120.70Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard
4、was published under the authority of theStandards Policy and Strategy Committee on 31 October 2013.Amendments/corrigenda issued since publicationDate Text affectedBRITISH STANDARDBS EN 60255-149:2013EUROPEAN STANDARD EN 60255-149 NORME EUROPENNE EUROPISCHE NORM October 2013 CENELEC European Committe
5、e for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung CEN-CENELEC Management Centre: Avenue Marnix 17, B - 1000 Brussels 2013 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CEN
6、ELEC members. Ref. No. EN 60255-149:2013 E ICS 29.120.70 Supersedes EN 60255-8:1998 English version Measuring relays and protection equipment - Part 149: Functional requirements for thermal electrical relays (IEC 60255-149:2013) Relais de mesure et dispositifs de protection - Partie 149: Exigences f
7、onctionnelles pour les relais lectriques thermiques (CEI 60255-149:2013) Messrelais und Schutzeinrichtungen - Teil 149: Funktionsanforderungen an den thermischen berlastschutz (IEC 60255-149:2013) This European Standard was approved by CENELEC on 2013-09-03. CENELEC members are bound to comply with
8、the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Managem
9、ent Centre or to any CENELEC member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the sa
10、me status as the official versions. CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Li
11、thuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. BS EN 60255-149:2013EN 60255-149:2013 - 2 - Foreword The text of document 95/313/FDIS, future edition 1 of IEC 60255-149, prepared by IEC/TC
12、95 “Measuring relays and protection equipment“ was submitted to the IEC-CENELEC parallel vote and approved by CENELEC as EN 60255-149:2013. The following dates are fixed: latest date by which the document has to be implemented at national level by publication of an identical national standard or by
13、endorsement (dop) 2014-06-03 latest date by which the national standards conflicting with the document have to be withdrawn (dow) 2016-09-03 This document supersedes EN 60255-8:1998. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights.
14、 CENELEC and/or CEN shall not be held responsible for identifying any or all such patent rights. Endorsement notice The text of the International Standard IEC 60255-149:2013 was approved by CENELEC as a European Standard without any modification. In the official version, for Bibliography, the follow
15、ing notes have to be added for the standards indicated: IEC 60034-11 NOTE Harmonized as EN 60034-11. IEC 60947-4-1 NOTE Harmonized as EN 60947-4-1. IEC 60947-4-2 NOTE Harmonized as EN 60947-4-2. IEC 61850-9-2 NOTE Harmonized as EN 61850-9-2. BS EN 60255-149:2013- 3 - EN 60255-149:2013 Annex ZA (norm
16、ative) Normative references to international publications with their corresponding European publications The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For unda
17、ted references, the latest edition of the referenced document (including any amendments) applies. NOTE When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD applies. Publication Year Title EN/HD Year IEC 60050 Series International Electro
18、technical Vocabulary (IEV) - - IEC 60085 2007 Electrical insulation - Thermal evaluation and designation EN 60085 2008 IEC 60255-1 - Measuring relays and protection equipment - Part 1: Common requirements EN 60255-1 - IEC 61850-7-4 - Communication networks and systems for power utility automation -
19、Part 7-4: Basic communication structure - Compatible logical node classes and data object classes EN 61850-7-4 - BS EN 60255-149:2013 2 60255-149 IEC:2013 CONTENTS 1 Scope . 6 2 Normative references . 6 3 Terms and definitions . 7 4 Specification of the function 8 General . 8 4.1Input energizing qua
20、ntities/energizing quantities . 9 4.2Binary input signals . 9 4.3Functional logic . 10 4.4Equivalent heating current . 10 4.4.1Basic (setting) and operating current values for thermal protection 10 4.4.2Thermal level calculation . 11 4.4.3Time-current limit characteristic equations and curves . 12 4
21、.4.4Thermal level alarm threshold 14 4.4.5Binary output signals . 15 4.5General . 15 4.5.1Operate (trip) output signal 15 4.5.2Alarm signal 15 4.5.3Other binary output signals 15 4.5.4Additional influencing factors on thermal protection . 16 4.6General . 16 4.6.1Influence of ambient temperature on t
22、hermal protection . 16 4.6.2Thermal reset facilities 16 4.6.3Behaviour of thermal protective device during auxiliary power supply failure . 17 4.75 Performance specification 17 Accuracy related to the characteristic quantity . 17 5.1Accuracy related to the operate time . 17 5.2Performance during fre
23、quency variations . 18 5.36 Functional test methodology . 18 General . 18 6.1Determination of steady-state errors related to the operating current value . 19 6.2Determination of steady-state errors related to the characteristic quantity and 6.3the operate time 19 Accuracy determination of the cold c
24、urve . 19 6.3.1Accuracy determination of the hot curves 20 6.3.2Performance with specific cooling thermal time constant . 21 6.4Performance with harmonics . 22 6.5Performance during frequency variations . 22 6.6Performance during different ambient temperatures 23 6.77 Documentation requirements 24 T
25、ype test report . 24 7.1Other user documentation . 24 7.2Annex A (informative) Simple first-order thermal model of electrical equipment 26 Annex B (informative) Thermal electrical relays which use temperature as setting parameters . 41 Bibliography 46 BS EN 60255-149:201360255-149 IEC:2013 3 Figure
26、1 Simplified thermal protection function block diagram 9 Figure 2 Typical examples of characteristic curves for cold state of a first-order thermal system with no previous load before overload occurs . 13 Figure 3 Typical examples of characteristic curves for hot states of a first-order thermal syst
27、em for different values of previous load before overload occurs . 14 Figure A.1 An electrical equipment to be thermally protected represented as a simple first-order thermal system 26 Figure A.2 Equivalence between a first-order thermal system and an electric parallel RC circuit 30 Figure A.3 Analog
28、ue thermal circuit representation of a simple first-order thermal system 31 Figure A.4 Analogue thermal circuit representation of a simple first-order thermal system motor starting condition 31 Figure A.5 Analogue thermal circuit representation of a simple first-order thermal system motor stopped co
29、ndition . 31 Figure A.6 Dynamic step response of a simple first-order thermal system algorithm to a current below pickup 33 Figure A.7 Dynamic step response of a first-order thermal system (cold initial state) . 34 Figure A.8 Dynamic step response of a first-order thermal system (hot initial state)
30、. 34 Figure A.9 Dynamic step response of a first-order thermal system to a load current followed by an overload current (initial state: cold) 35 Figure A.10 Dynamic step response of a first-order thermal system to a load current followed by an overload current (initial state: hot) . 35 Table 1 Limit
31、ing error as multiples of assigned error 18 Table 2 Test points of the cold curve . 20 Table 3 Test points of the hot curve . 21 Table 4 Test points of the cold curve with harmonics . 22 Table 5 Test points of the cold curve during frequency variations 22 Table A.1 Thermal and electrical models 30 T
32、able A.2 Thermal insulation classes and maximum temperatures, according to IEC 60085. 40 Table A.3 Example of correction factor values (Fa) for class F equipment according to the ambient temperature (Ta) 40 BS EN 60255-149:2013 6 60255-149 IEC:2013 MEASURING RELAYS AND PROTECTION EQUIPMENT Part 149:
33、 Functional requirements for thermal electrical relays 1 Scope This part of the IEC 60255 series specifies minimum requirements for thermal protection relays. This standard includes specification of the protection function, measurement characteristics and test methodologies. The object of this stand
34、ard is to establish a common and reproducible reference for evaluating dependent time relays which protect equipment from thermal damage by measuring a.c. current flowing through the equipment. Complementary input energizing quantities such as ambient, coolant, top oil and winding temperature may be
35、 applicable for the thermal protection specification set forth in this standard. This standard covers protection relays based on a thermal model with memory function. The test methodologies for verifying performance characteristics of the thermal protection function and accuracy are also included in
36、 this Standard. This standard does not intend to cover the thermal overload protection trip classes indicated in IEC 60947-4-1 and IEC 60947-4-2, related to electromechanical and electronic protection devices for low voltage motor-starters. The thermal protection functions covered by this standard a
37、re as follows: Protection function IEC 61850-7-4 IEEE C37.2 Thermal overload protection PTTR 49 Rotor thermal overload protection PROL 49R Stator thermal overload protection PSOL 49S General requirements for measuring relays and protection equipment are specified in IEC 60255-1. 2 Normative referenc
38、es The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. IEC
39、60050 (all parts), International Electrotechnical Vocabulary (available at http:/www.electropedia.org) IEC 60085, Electrical insulation Thermal evaluation and designation IEC 60255-1, Measuring relays and protection equipment Part 1: Common requirements IEC 61850-7-4, Communication networks and syst
40、ems for power utility automation Part 7-4: Basic communication structure Compatible logical node classes and data classes BS EN 60255-149:201360255-149 IEC:2013 7 3 Terms and definitions For the purpose of this document, the terms and definitions given in IEC 60050-447, as well as the following appl
41、y. 3.1hot curve for a thermal electrical relay with a total memory function, characteristic curve representing the relationship between specified operating time and current, taking into account thermal effect of a specified steady-state load current before the overload occurs Note 1 to entry: Hot cu
42、rve is a plot of a particular time-current solution for a first-order thermal system differential equation, assuming a specific constant overload current and a specific preload current. 3.2cold curve for a thermal electrical relay, characteristic curve representing the relationship between specified
43、 operating time and current, with the relay at reference and steady-state conditions with no-load current flowing before the overload occurs Note 1 to entry: Cold curve is a plot of a particular time-current solution for a first-order thermal system differential equation, assuming a specific constan
44、t overload current when there is no preload. 3.3basic current IBspecified limiting (nominal) value of the current for which the relay is required not to operate at steady-state conditions of the equipment to be thermally protected Note 1 to entry: The basic current serves as a reference for the defi
45、nition of the operational characteristics of thermal electrical relays. The basic settings of a thermal electrical protection function are made in terms of this basic current (IB) and the thermal time constant () of the protected equipment. 3.4equivalent heating current Ieqcurrent which takes into a
46、ccount the additional heating sources such as imbalance currents and/or harmonics 3.5factor k factor by which the basic current (IB) is multiplied to obtain the maximum permissible continuous operating current value of the equipment to be thermally protected, which is used in the thermal characteris
47、tic function Note 1 to entry: The factor k indicates the maximum permissible constant between phase current (full load) and the basic (nominal) current of the protected equipment. 3.6previous load ratio ratio of the load current preceding the overload to basic current under specified conditions 3.7r
48、eference limiting error limiting error determined under reference conditions SOURCE: IEC 60050:2010, 447-08-07 BS EN 60255-149:2013 8 60255-149 IEC:2013 3.8temperature rise difference between the temperature of the part under consideration and a reference temperature Note 1 to entry: The reference t
49、emperature may be for example the ambient air temperature or the temperature of a cooling fluid. SOURCE: IEC 60050:2001, 151-16-26 3.9thermal equilibrium thermal state reached when the temperature rise of the several parts of the machine do not vary by more than a gradient of 2 K per hour SOURCE: IEC 60050:1996, 411-51-08 3.10thermal time constant Tthtime required for the temperature rise of the protected equipment relative to its initial temperature, to reach 63,2 % of it
