1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI British StandardsWB9423_BSI_StandardColCov_noK_AW:BSI FRONT COVERS 5/9/08 12:55 Page 1Electrical insulation systems Procedures for thermal evaluation Part 1: General requirements Low-voltageBS EN 618
2、57-1:2009National forewordThis British Standard is the UK implementation of EN 61857-1:2009. It isidentical to IEC 61857-1:2008. It supersedes BS EN 61857-1:2005 which iswithdrawn.The UK participation in its preparation was entrusted to Technical CommitteeGEL/112, Evaluation and qualification of ele
3、ctrical insulating materials andsystems.A list of organizations represented on this committee can be obtained onrequest to its secretary.This publication does not purport to include all the necessary provisions of acontract. Users are responsible for its correct application. BSI 2009 ISBN 978 0 580
4、62003 4 ICS 29.080.30Compliance with a British Standard cannot confer immunity from legal obligations.This British Standard was published under the authority of the StandardsPolicy and Strategy Committee on 30 September 2009Amendments issued since publicationAmd. No. Date Text affectedBRITISH STANDA
5、RDBS EN 61857-1:2009EUROPEAN STANDARD EN 61857-1 NORME EUROPENNE EUROPISCHE NORM January 2009 CENELEC European Committee for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: avenue Marnix 17, B - 10
6、00 Brussels 2009 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members. Ref. No. EN 61857-1:2009 E ICS 29.080.30 Supersedes EN 61857-1:2005English version Electrical insulation systems - Procedures for thermal evaluation - Part 1: General requiremen
7、ts - Low-voltage (IEC 61857-1:2008) Systmes disolation lectrique - Procdures dvaluation thermique - Partie 1: Exigences gnrales - Basse tension (CEI 61857-1:2008) Elektrische Isoliersysteme - Verfahren zur thermischen Bewertung - Teil 1: Allgemeine Anforderungen - Niederspannung (IEC 61857-1:2008) T
8、his European Standard was approved by CENELEC on 2008-12-01. CENELEC members are bound to comply with 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 r
9、eferences concerning such national standards may be obtained on application to the Central Secretariat 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 CENEL
10、EC member into its own language and notified to the Central Secretariat has the same status as the official versions. CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Cyprus, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, I
11、celand, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. BS EN 61857-1:2009EN 61857-1:2009 - 2 - Foreword The text of document 112/92/CDV, future edition 3 of IEC 61857-1,
12、prepared by IEC TC 112, Evaluation and qualification of electrical insulating materials and systems, was submitted to the IEC-CENELEC parallel vote and was approved by CENELEC as EN 61857-1 on 2008-12-01. This European Standard supersedes EN 61857-1:2005 and constitutes editorial revisions to make E
13、N 61857-1:2009 compatible with Parts 21 and 22. The following dates were fixed: latest date by which the EN has to be implemented at national level by publication of an identical national standard or by endorsement (dop) 2009-09-01 latest date by which the national standards conflicting with the EN
14、have to be withdrawn (dow) 2011-12-01 Annex ZA has been added by CENELEC. _ Endorsement notice The text of the International Standard IEC 61857-1:2008 was approved by CENELEC as a European Standard without any modification. In the official version, for Bibliography, the following notes have to be ad
15、ded for the standards indicated: IEC 60034-18-1 NOTE Harmonized as EN 60034-18-1:1994 (not modified). IEC 60034-18-21 NOTE Harmonized as EN 60034-18-21:1994 (not modified). IEC 60034-18-31 NOTE Harmonized as EN 60034-18-31:1994 (not modified). IEC 62114 NOTE Harmonized as EN 62114:2001 (not modified
16、). _ BS EN 61857-1:2009- 3 - EN 61857-1:2009 Annex ZA (normative) Normative references to international publications with their corresponding European publications The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited
17、applies. For undated 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 60085 2004 Electr
18、ical insulation - Thermal classification EN 60085 1) 2004 IEC 60216-4-1 - 2)Electrical insulating materials - Thermal endurance properties - Part 4-1: Ageing ovens - Single-chamber ovens EN 60216-4-1 2006 3)IEC 60216-5 - 2)Electrical insulating materials - Thermal endurance properties - Part 5: Dete
19、rmination of relative thermal endurance index (RTE) of an insulating material EN 60216-5 2008 3)IEC 60493-1 - 2)Guide for the statistical analysis of ageing test data - Part 1: Methods based on mean values of normally distributed test results - - IEC 60505 2004 Evaluation and qualification of electr
20、ical insulation systems EN 60505 2004 1)EN 60085 is superseded by EN 60085:2008, which is based on IEC 60085:2007. 2)Undated reference. 3) Valid edition at date of issue. BS EN 61857-1:2009 2 61857-1 IEC:2008 CONTENTS INTRODUCTION.5 1 Scope.6 2 Normative references6 3 Terms and definitions .6 4 Gene
21、ral information 8 4.1 Overview of test procedure 8 4.2 Basis of evaluation and qualification 8 4.3 Specific requirements 8 5 Test objects9 5.1 General .9 5.2 Description 9 5.3 Number of test objects.9 6 Test procedures9 6.1 General .9 6.2 Initial screening tests.9 6.3 Thermal ageing .10 6.4 Prediagn
22、ostic mechanical stress11 6.5 Other prediagnostic conditioning11 6.6 Moisture exposure .12 6.7 Dielectric diagnostic tests 12 6.8 Other diagnostic tests12 7 Analyzing, reporting and classification.12 7.1 End-point criterion .12 7.2 Method of determining life13 7.3 Extrapolation of data13 7.4 Report
23、of results14 Bibliography16 Figure 1 Arrhenius graph for comparing a candidate system C with a reference system R.15 Table 1 Suggested ageing temperatures and ageing periods.10 Table 2 Thermal class assignment .13 BS EN 61857-1:200961857-1 IEC:2008 5 INTRODUCTION This International Standard establis
24、hes a standardized test procedure for estimating by comparison the life expectancy of electrical insulation systems (EIS) in accordance with IEC 60505. An EIS contains many different components selected to withstand the varying electrical, mechanical, and thermal stresses occurring in the different
25、parts of the structure of an electrotechnical product. The useful life of an EIS depends upon the way that its individual components are arranged, their interactions upon each other, and the contribution of each component to the electrical and mechanical integrity of the EIS. Therefore, it is imposs
26、ible to specify one test object to represent all electrotechnical products. It is incumbent upon the IEC equipment technical committees to address the test objects and application of this test procedure that will meet their specific needs. This work is intended to proceed by cooperation between this
27、 technical committee and other IEC technical committees to develop a series of parts, each part to address a specific test object and/or application. This procedure permits approximate comparisons only, and cannot be relied upon to completely determine the merits of any particular EIS. Such informat
28、ion can be obtained only from extended service experience. BS EN 61857-1:2009 6 61857-1 IEC:2008 ELECTRICAL INSULATION SYSTEMS PROCEDURES FOR THERMAL EVALUATION Part 1: General requirements Low voltage 1 Scope This part of IEC 61857 specifies a general test procedure for the thermal evaluation and q
29、ualification of electrical insulation systems (EIS) and establishes a procedure that compares the performance of a candidate EIS to that of a reference EIS. This standard is applicable to existing or proposed EIS used in electrotechnical products with an input voltage of up to 1 000 V where the ther
30、mal factor is the dominating ageing factor. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any ame
31、ndments) applies. IEC 60085:2004, Electrical insulation Thermal evaluation and designation IEC 60216-4-1, Electrical insulating materials Thermal endurance properties Part 4-1: Ageing ovens Single chamber ovens IEC 60216-5, Electrical insulating materials Thermal endurance properties Part 5: Determi
32、nation of relative thermal endurance index (RTE) of an insulating material IEC 60493-1, Guide for the statistical analysis of ageing test data Part 1: Methods based on mean values of normally distributed test results IEC 60505:2004, Evaluation and qualification of electrical insulation systems 3 Ter
33、ms and definitions For the purposes of this document, the terms and definitions given in IEC 60505, as well as the following definitions, apply. 3.1 electrical insulation system EIS insulating structure containing one or more electrical insulating materials (EIM) together with associated conducting
34、parts employed in an electrotechnical device IEC 60505, definition 3.1.1 NOTE EIM with different temperature indices (ATE/RTE according to IEC 60216-5) may be combined to form an EIS which has a thermal class that may be higher or lower than that of any of the individual components according to IEC
35、60505. 3.2 candidate EIS EIS under evaluation to determine its service capability (thermal) BS EN 61857-1:200961857-1 IEC:2008 7 3.3 reference EIS established EIS evaluated on the basis of either a known service experience record or a known comparative functional evaluation 3.4 thermal class designa
36、tion of an EIS that is equal to the numerical value of the maximum use temperature in degrees Celsius (C) for which the EIS is appropriate (see IEC 60085) NOTE The EIS may be subjected to operating temperatures exceeding its thermal class which can result in shorter expected life. 3.5 EIS assessed t
37、hermal endurance index EIS ATE numerical value of temperature in degrees Celsius for the reference EIS as derived from known service experience or a known comparative functional evaluation 3.6 EIS relative thermal endurance index EIS RTE numerical value of the temperature in degrees Celsius for the
38、candidate EIS which is relative to the known EIS ATE of a reference EIS, when both EIS are subjected to the same ageing and diagnostic procedures in a comparative test 3.7 test object sample of original equipment or part thereof, or model representing the equipment completely or partially, including
39、 the EIS, to be used in a functional test 3.8 thermal ageing factor thermal stress that causes irreversible changes of the properties of an EIS 3.9 prediagnostic conditioning variable or fixed stresses, which can be applied continuously or periodically to an EIS to enhance the ability of a functiona
40、l test to detect the degree of ageing NOTE Prediagnostic conditioning may cause additional ageing. 3.10 diagnostic test periodic or continuous application of a specified level of a diagnostic factor to a test object to determine whether or when the end-point criterion has been reached 3.11 end-point
41、 criterion value of either a property or change of property defining the end of life of a test object in a functional test 3.12 end-of-life end of a test objects life as determined by meeting its end-point criterion BS EN 61857-1:2009 8 61857-1 IEC:2008 4 General information 4.1 Overview of test pro
42、cedure This thermal ageing test procedure is based on the fact that, for most materials, thermal ageing is accelerated when temperature is raised, and that often the degree of acceleration obeys the Arrhenius law on chemical reaction rates. Based on this relationship, acceptable extrapolation of the
43、 ageing test results may be used to determine the anticipated thermal performance of the candidate EIS. Accelerated thermal testing requires the verification of an identical or equivalent ageing mechanism compared under operating service conditions. Test objects consisting of the candidate EIS are e
44、xposed to thermal ageing cycles at selected temperatures. Each cycle consists of a specific time exposure at elevated temperature and a subcycle of exposure to prediagnostic conditioning and diagnostic tests. Prediagnostic conditioning may include mechanical stress, cold shock and moisture exposure.
45、 A dielectric diagnostic test is used to determine test life. A reference EIS is tested using the same test procedure. At each ageing temperature, the test life of the EIS is determined. Based on these test life values, the thermal class of the candidate EIS is estimated relative to the performance
46、of the reference EIS in its thermal class. 4.2 Basis of evaluation and qualification The functional testing and evaluation, according to this test procedure, shall be made on a comparative basis, using an established EIS as a reference which is tested with the candidate EIS in equivalent fashion. If
47、 the thermal classes for the candidate and reference EIS differ, then appropriate ageing temperatures are used for each. 4.3 Specific requirements Separate Parts in the IEC 61857 series address specific test objects and/or applications and test procedures. Test objects are unique to each part becaus
48、e testing of specific electrotechnical products, or representations thereof, may yield results that are not applicable to other electrotechnical products. Different electrotechnical products may also require alternative methods of thermal ageing and/or diagnostic tests due to design considerations o
49、r end-use requirements. Each Part shall specify the following: scope: electrotechnical products that this test object represents; construction of the test object (5.2); number of test objects required (5.3); test procedures: specific requirements and means of testing for initial dielectric diagnostic test (6.7.1); prediagnostic mechanical stress (6.4); other prediagnostic conditioning, as required (6.5); moisture exposure (6.6); dielectric diagnostic te
