EN 62059-31-1:2008

Electricity metering equipment - Dependability - Part 31-1: Accelerated reliability testing - Elevated temperature and humidity

IEC 62059-31-1:2008 provides one of several possible methods for estimating product life characteristics by accelerated reliability testing. In this standard, elevated, constant temperature and humidity is applied to achieve acceleration. The method takes into account the effect of voltage and current variation. It 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 equipment prior to and during serial production. This method may also be used to compare different designs. The contents of the corrigendum of December 2008 have been included in this copy.

Elektrizitätszähler - Zuverlässigkeit - Teil 31-1: Zeitraffende Zuverlässigkeitsprüfung - Temperatur und Luftfeuchte erhöht

Equipements de comptage de l'électricité - Sûreté de fonctionnement - Partie 31-1: Essais de fiabilité accélérés - Température et humidité élévées

La CEI 62059-31-1:2008 fournit une méthode, parmi de nombreuses autres, de prévision des caractéristiques de la duré de vie d'un produit au moyen des essais de fiabilité accélérés. Elle utilise une température et une humidité constantes élevées pour parvenir à ladite accélération. La méthode utilisée tient également compte de l'effet de variation de la tension et du courant. Elle s'applique à tous les types d'équipement de comptage de l'énergie et de contrôle des tarifs et de la charge relevant du domaine d'application du comité d'études 13 de la CEI. La méthode décrite dans la présente norme peut être utilisée pour évaluer (avec des limites de confiance données) les caractéristiques de la durée de vie de ces équipements avant et au cours de leur fabrication en série. Cette méthode peut également être employée pour comparer des équipements de conceptions différentes. Le contenu du corrigendum de décembre 2008 a été pris en considération dans cet exemplaire.

Oprema za merjenje električne energije - Zagotovljivost - 31-1. del: Pospešeno preskušanje zanesljivosti - Povišana temperatura in povečana vlažnost (IEC 62059-31-1:2008)

General Information

• Status: Published
• Publication Date: 20-Nov-2008
• Withdrawal Date: 31-Oct-2011
• ICS: 29.240 - Power transmission and distribution networks
• ICS: 91.140.50 - Electricity supply systems
• Technical Committee: CLC/TC 13 - Equipment for electrical energy measurement and load control
• Drafting Committee: IEC/TC 13 - IEC_TC_13
• Parallel Committee: IEC/TC 13 - IEC_TC_13
• Current Stage: 6060 - Document made available - Publishing
• Start Date: 21-Nov-2008
• Completion Date: 21-Nov-2008
• Ref Project: SIST EN 62059-31-1:2009 - Electricity metering equipment - Dependability - Part 31-1: Accelerated reliability testing - Elevated temperature and humidity (IEC 62059-31-1:2008)

Standards Content (Sample)

SLOVENSKI STANDARD
01-januar-2009
2SUHPD]DPHUMHQMHHOHNWULþQHHQHUJLMH=DJRWRYOMLYRVWGHO3RVSHãHQR
SUHVNXãDQMH]DQHVOMLYRVWL3RYLãDQDWHPSHUDWXUDLQSRYHþDQDYODåQRVW,(&

Electricity metering equipment - Dependability - Part 31-1: Accelerated reliability testing -
Elevated temperature and humidity (IEC 62059-31-1:2008)
Elektrizitätszähler - Zuverlässigkeit - Teil 31-1: Zeitraffende Zuverlässigkeitsprüfung -
Temperatur und Luftfeuchte erhöht (IEC 62059-31-1:2008)
Equipements de comptage de l'électricité - Sûreté de fonctionnement - Partie 31-1:
Essais de fiabilité accélérés - Température et humidité élévées (CEI 62059-31-1:2008)
Ta slovenski standard je istoveten z: EN 62059-31-1:2008
ICS:
17.220.20 0HUMHQMHHOHNWULþQLKLQ Measurement of electrical
PDJQHWQLKYHOLþLQ and magnetic quantities
91.140.50 Sistemi za oskrbo z elektriko Electricity supply systems
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN 62059-31-1
NORME EUROPÉENNE
November 2008
EUROPÄISCHE NORM
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 l'électricité - Elektrizitätszähler -
Sûreté de fonctionnement - Zuverlässigkeit -
Partie 31-1: Essais de fiabilité accélérés - Teil 31-1: Zeitraffende
Température et humidité élévées Zuverlässigkeitsprüfung -
(CEI 62059-31-1:2008) Temperatur und Luftfeuchte erhöht
(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/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 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 CENELEC 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, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland and the United Kingdom.

CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für 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 E
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 IEC-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 national 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 Bibliography, 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 modified).
__________
- 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 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 60050-191 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 2008

IEC 61703 2001 Mathematical expressions for reliability, EN 61703 2002
availability, maintainability and maintenance
support terms
IEC/TR 62059-11 2002 Electricity metering equipment - - -
Dependability -
Part 11: General concepts
IEC/TR 62059-21 2002 Electricity metering equipment - - -
Dependability -
Part 21: Collection of meter dependability data
from the field
IEC 62059-41 2006 Electricity metering equipment - EN 62059-41 2006
Dependability -
Part 41: Reliability prediction

IEC 62308 2006 Equipment reliability - Reliability assessment EN 62308 2006
methods
IEC 62059-31-1
Edition 1.0 2008-10
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Electricity metering equipment – Dependability –
Part 31-1: Accelerated reliability testing – Elevated temperature and humidity

Equipements de comptage de l'électricité – Sûreté de fonctionnement –
Partie 31-1: Essais de fiabilité accélérés – Température et humidité élevées

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
XC
CODE PRIX
ICS 29.240; 91.140.50 ISBN 2-8318-1002-9
– 2 – 62059-31-1 © IEC:2008
CONTENTS
FOREWORD.5
INTRODUCTION.7
1 Scope.8
2 Normative references .8
3 Terms and definitions .9
4 Symbols, acronyms and abbreviations.14
5 Description of quantitative accelerated life tests .15
5.1 Introduction .15
5.2 The life distribution.15
5.3 The life-stress model .15
6 The Weibull distribution .16
6.1 Introduction .16
6.2 Graphical representation .16
6.3 Calculation of the distribution parameters.19
6.3.1 Input data to be used.19
6.3.2 Ranking of the time to failure.19
6.3.3 Reliability / unreliability estimates.20
6.3.4 Calculation of the parameters .21
7 The life-stress model .25
7.1 General .25
7.2 Linear equation of the acceleration factor.26
7.3 Calculation of parameters n and E .27
a
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 .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 to 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 root cause of failures .34
11 Presentation of the results.34
11.1 Information to be given.34
11.2 Example .35
12 Special cases .35
12.1 Cases of simplification .35
12.1.1 Minor evolution of product design .35

62059-31-1 © IEC:2008 – 3 –
12.1.2 Verification of production batches.35
12.2 Cases when additional information is needed .35
12.2.1 The β 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 the Weibull distribution.38
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 Γ(n) .47
Annex F (normative) Calculation of the minimum duration of the maximum stress level
test .48
Annex G (informative) Example.54
Bibliography.84
INDEX .85

Figure 1 – Weibull unreliability representation example with γ = 3 000, β = 1,1, η = 10 000.19
Figure 2 – Example of graphical representation of F(t) in the case of Weibull
distribution.25
Figure 3 – Example of regional climatic conditions.30
Figure 4 – Calculation of average year use conditions .31
Figure A.1 – The probability density function .36
Figure A.2 – The rel
...