1、Electricity metering equipment Dependability Part 31-1: Accelerated reliability testing Elevatedtemperature and humidityBS EN 62059-31-1:2008raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI British StandardsNational forewordThis British Standard is
2、 the UK implementation of EN 62059-31-1:2008. It isidentical to IEC 62059-31-1:2008.The UK participation in its preparation was entrusted to Technical CommitteePEL/13, Electricity meters.A list of organizations represented on this committee can be obtained onrequest to its secretary.This publication
3、 does not purport to include all the necessary provisions of acontract. Users are responsible for its correct application. BSI 2008ISBN 978 0 580 53559 8ICS 91.140.50BRITISH STANDARDBS EN 62059-31-1:2008Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Stan
4、dard was published under the authority of the StandardsPolicy and Strategy Committee on 31 March 2009 Amendments issued since publicationAmd. No. Date Text affectedEUROPEAN STANDARD EN 62059-31-1 NORME EUROPENNE EUROPISCHE NORM November 2008 CENELEC European Committee for Electrotechnical Standardiz
5、ation Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: rue de Stassart 35, B - 1050 Brussels 2008 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members. Ref. No. EN 62059-31-1:2008
6、 E ICS 29.240; 91.140.50 English version Electricity metering equipment - Dependability - Part 31-1: Accelerated reliability testing - Elevated temperature and humidity (IEC 62059-31-1:2008) Equipements de comptage de llectricit -Sret de fonctionnement - Partie 31-1: Essais de fiabilit acclrs - Temp
7、rature et humidit lves (CEI 62059-31-1:2008) Elektrizittszhler -Zuverlssigkeit - Teil 31-1: Zeitraffende Zuverlssigkeitsprfung - Temperatur und Luftfeuchte erhht (IEC 62059-31-1:2008) This European Standard was approved by CENELEC on 2008-11-01. CENELEC members are bound to comply with the CEN/CENEL
8、EC 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 Central Secretariat or to any CE
9、NELEC 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 Central Secretariat has the same status as the official version
10、s. CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Cyprus, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, S
11、lovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. BS EN 62059-31-1:2008EN 62059-31-1:2008 - 2 - Foreword The text of document 13/1437A/FDIS, future edition 1 of IEC 62059-31-1, prepared by IEC TC 13, Electrical energy measurement, tariff- and load control, was submitted to the IE
12、C-CENELEC parallel vote and was approved by CENELEC as EN 62059-31-1 on 2008-11-01. 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) 2009-08-01 latest date by which the nationa
13、l standards conflicting with the EN have to be withdrawn (dow) 2011-11-01 Annex ZA has been added by CENELEC. _ Endorsement notice The text of the International Standard IEC 62059-31-1:2008 was approved by CENELEC as a European Standard without any modification. In the official version, for Bibliogr
14、aphy, the following notes have to be added for the standards indicated: IEC 61124 NOTE Harmonized as EN 61124:2006 (not modified). IEC 61163-1 NOTE Harmonized as EN 61163-1:2006 (not modified). IEC 61164 NOTE Harmonized as EN 61164:2004 (not modified). IEC 61709 NOTE Harmonized as EN 61709:1998 (not
15、 modified). _ BS EN 62059-31-1:2008- 3 - EN 62059-31-1:2008 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
16、 edition cited 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 60
17、050-191 1990 International Electrotechnical Vocabulary (IEV) - Chapter 191: Dependability and quality of service - - IEC 60300-3-5 2001 Dependability management - Part 3-5: Application guide - Reliability test conditions and statistical test principles - - IEC 61649 2008 Weibull analysis EN 61649 20
18、08 IEC 61703 2001 Mathematical expressions for reliability, availability, maintainability and maintenance support terms EN 61703 2002 IEC/TR 62059-11 2002 Electricity metering equipment - Dependability - Part 11: General concepts - - IEC/TR 62059-21 2002 Electricity metering equipment - Dependabilit
19、y - Part 21: Collection of meter dependability data from the field - - IEC 62059-41 2006 Electricity metering equipment - Dependability - Part 41: Reliability prediction EN 62059-41 2006 IEC 62308 2006 Equipment reliability - Reliability assessment methods EN 62308 2006 BS EN 62059-31-1:2008 2 62059
20、-31-1 IEC:2008 CONTENTS INTRODUCTION.7 1 Scope.8 2 Normative references .8 3 Terms and definitions .9 4 Symbols, acronyms and abbreviations14 5 Description of quantitative accelerated life tests .15 5.1 Introduction .15 5.2 The life distribution15 5.3 The life-stress model.15 6 The Weibull distribut
21、ion 16 6.1 Introduction .16 6.2 Graphical representation .16 6.3 Calculation of the distribution parameters19 6.3.1 Input data to be used.19 6.3.2 Ranking of the time to failure.19 6.3.3 Reliability / unreliability estimates20 6.3.4 Calculation of the parameters 21 7 The life-stress model 25 7.1 Gen
22、eral .25 7.2 Linear equation of the acceleration factor26 7.3 Calculation of parameters n and Ea.27 8 The quantitative accelerated life testing method .28 8.1 Selection of samples .28 8.2 The steps to check product life characteristics 28 8.3 Procedure for terminating the maximum stress level test .
23、29 8.4 Procedure to collect time to failure data and to repair meters 29 9 Definition of normal use conditions .29 9.1 Introduction .29 9.2 Temperature and humidity conditions 30 9.2.1 Equipment for outdoor installation .30 9.2.2 Equipment for indoor installation .31 9.3 Temperature correction due t
24、o variation of voltage and current .31 9.3.1 Definition of the normal use profile of voltage and current .32 9.3.2 Measurement of the meter internal temperature at each current and voltage 32 9.3.3 Calculation of the meter average internal temperature.32 9.4 Other conditions 34 10 Classification and
25、 root cause of failures .34 11 Presentation of the results34 11.1 Information to be given34 11.2 Example 35 12 Special cases .35 12.1 Cases of simplification 35 12.1.1 Minor evolution of product design 35 BS EN 62059-31-1:200862059-31-1 IEC:2008 3 12.1.2 Verification of production batches35 12.2 Cas
26、es when additional information is needed 35 12.2.1 The parameter changes significantly from maximum stress level to medium or low stress level 35 12.2.2 Fault mode different between stress levels 35 Annex A (informative) Basic statistical background 36 Annex B (informative) The characteristics of th
27、e Weibull distribution38 Annex C (informative, see also draft IEC 62308) Life-stress models 42 Annex D (normative) Rank tables.44 Annex E (normative) Values of the Gamma function (n) .47 Annex F (normative) Calculation of the minimum duration of the maximum stress level test .48 Annex G (informative
28、) Example54 Bibliography84 INDEX 85 Figure 1 Weibull unreliability representation example with = 3 000, = 1,1, = 10 000.19 Figure 2 Example of graphical representation of F(t) in the case of Weibull distribution25 Figure 3 Example of regional climatic conditions30 Figure 4 Calculation of average yea
29、r use conditions 31 Figure A.1 The probability density function 36 Figure A.2 The reliability and unreliability functions .37 Figure B.1 Effect of the parameter on the Weibull probability density function )(tf 39 Figure B.2 Effect of the parameter on the Weibull probability density function )(tf 40
30、Figure F.1 Unreliability at normal use conditions49 Figure F.2 Unreliability at maximum stress level 50 Figure G.1 Graphical representation of display failures for each stress level63 Figure G.2 Graphical representation of Q2 failures for each stress level 64 Figure G.3 Graphical representation of U
31、1 failures for each stress level 65 Figure G.4 Example of climate data .67 Figure G.5 Graphical representation of all failures at normal use conditions 76 Figure G.6 Final cumulative distribution with confidence intervals 81 Figure G.7 Reliability function extrapolated to normal use conditions .82 F
32、igure G.8 Reliability function extrapolated to normal use conditions (First portion magnified).83 Table 1 Construction of ordinate (Y) 17 Table 2 Construction of abscissa (t-) 17 Table 3 Equations format entered into a spreadsheet 18 Table 4 Example with = 3 000, = 1,1, = 10 000 18 Table 5 Example o
33、f ranking process of times to failure.20 Table 6 Unreliability estimates by median rank 21 Table 7 Example of unreliability estimation for Weibull distribution.24 BS EN 62059-31-1:2008 4 62059-31-1 IEC:2008 Table 8 Example of 90 % confidence bounds calculation for Weibull distribution24 Table 9 Valu
34、es of the linear equation.27 Table 10 Example of procedure for temperature correction 33 Table G.1 Failures logged at 85 C with RH = 95 % .57 Table G.2 Failures logged at 85 C with RH = 85 % .59 Table G.3 Failures logged at 85 C with RH = 75 % .60 Table G.4 Failures logged at 75 C with RH = 95 % .61
35、 Table G.5 Failures logged at 65 C with RH = 95 % .62 Table G.6 Best fit Weibull distributions for display failures .63 Table G.7 Best fit Weibull distributions for Q2 failures64 Table G.8 Best fit Weibull distributions for U1 failures65 Table G.9 Values of the linear equation for display failures66
36、 Table G.10 Values of the linear equation for Q2 failures 66 Table G.11 Values of the linear equation for other failures.66 Table G.12 Normal use profile of voltage and current.67 Table G.13 Measurement of the internal temperature.69 Table G.14 Arrhenius acceleration factors compared to temperature
37、measured at Unand 0,1 Imax, for display failures .70 Table G.15 Arrhenius acceleration factors compared to temperature measured at Unand 0,1 Imax, for Q2 failures71 Table G.16 Arrhenius acceleration factors compared to temperature measured at Unand 0,1 Imax, for U1 failures 72 Table G.17 Display fai
38、lures extrapolated to normal use conditions.74 Table G.18 Q2 failures extrapolated to normal use conditions75 Table G.19 U1 failures extrapolated to normal use conditions 76 Table G.20 Best fit Weibull distributions at normal use conditions77 Table G.21 Display failures 90 % confidence bounds calcul
39、ation .78 Table G.22 Q2 failures 90 % confidence bounds calculation 79 Table G.23 U1 failures 90 % confidence bounds calculation 80 BS EN 62059-31-1:200862059-31-1 IEC:2008 7 INTRODUCTION Electricity metering equipment are products designed for high reliability and long life under normal operating c
40、onditions, operating continuously without supervision. To manage metering assets effectively, it is important to have tools for predicting and estimating life characteristics of various types. IEC 62059-41 provides methods for predicting the failure rate assumed to be constant of metering equipment
41、based on the parts stress method. IEC 62059-31-1 provides a method for estimating life characteristics using temperature and humidity accelerated testing. It is practically impossible to obtain data about life characteristics by testing under normal operating conditions. Therefore, accelerated relia
42、bility test methods have to be used. During accelerated reliability testing, samples taken from a defined population are operated beyond their normal operating conditions, applying stresses to shorten the time to failure, but without introducing new failure mechanisms. The estimation is performed by
43、 recording and analysing failures during such accelerated testing, establishing the failure distribution under the test conditions and, using life stress models, extrapolating failure distribution under accelerated conditions of use to normal conditions of use. The method provides quantitative resul
44、ts with their confidence limits and may be used to compare life characteristics of products coming from different suppliers or different batches from the same supplier. BS EN 62059-31-1:2008 8 62059-31-1 IEC:2008 ELECTRICITY METERING EQUIPMENT DEPENDABILITY Part 31-1: Accelerated reliability testing
45、 Elevated temperature and humidity 1 Scope This part of IEC 62059 provides one of several possible methods for estimating product life characteristics by accelerated reliability testing. Acceleration can be achieved in a number of different ways. In this particular standard, elevated, constant tempe
46、rature and humidity is applied to achieve acceleration. The method also takes into account the effect of voltage and current variation. Of course, failures not (or not sufficiently) accelerated by temperature and humidity will not be detected by the application of the test method specified in this s
47、tandard. Other factors, like temperature variation, vibration, dust, voltage dips and short interruptions, static discharges, fast transient burst, surges, etc. although they may affect the life characteristics of the meter are not taken into account in this standard; they may be addressed in future
48、 parts of the IEC 62059 series. This standard is applicable to all types of metering equipment for energy measurement, tariff- and load control in the scope of IEC TC 13. The method given in this standard may be used for estimating (with given confidence limits) product life characteristics of such
49、equipment prior to and during serial production. This method may also be used to compare different designs. 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 (includ
