|
IEC 61123
Edition 2.0 2019-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Reliability testing – Compliance test plans for success ratio
Essais de fiabilité – Plans d'essai de conformité pour une proportion de succès
your local IEC member National Committee for further information.
Droits de reproduction réservés. Sauf indication contraire, aucune partie de cette publication ne peut être reproduite ni
utilisée sous quelque forme que ce soit et par aucun procédé, électronique ou mécanique, y compris la photocopie et
les microfilms, sans l'accord écrit de l'IEC ou du Comité national de l'IEC du pays du demandeur. Si vous avez des
questions sur le copyright de l'IEC ou si vous désirez obtenir des droits supplémentaires sur cette publication, utilisez
les coordonnées ci-après ou contactez le Comité national de l'IEC de votre pays de résidence.
IEC Central Office Tel.: +41 22 919 02 11
3, rue de
CH-1211 Geneva 20
Switzerland
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 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 corrigendum or an amendment might have been published.
IEC publications search - webstore.iec.ch/advsearchform Electropedia - www.electropedia.org
The advanced search enables to find IEC publications by a The world's leading online dictionary on electrotechnology,
variety of criteria (reference number, text, technical containing more than 22 000 terminological entries in English
committee,…). It also gives information on projects, replaced and French, with equivalent terms in 16 additional languages.
and withdrawn publications. Also known as the International Electrotechnical Vocabulary
(IEV) online.
IEC Just Published - webstore.iec.ch/justpublished
Stay up to date on all new IEC publications. Just Published IEC Glossary - std.iec.ch/glossary
details all new publications released. Available online and once 67 000 electrotechnical terminology entries in English and
a month by email. French extracted from the Terms and Definitions clause of IEC
publications issued since 2002. Some entries have been
IEC Customer Service Centre - webstore.iec.ch/csc collected from earlier publications of IEC TC 37, 77, 86 and
If you wish to give us your feedback on this publication or need CISPR.
further assistance, please contact the Customer Service
.
A propos de l'IEC
La Commission Electrotechnique Internationale (IEC) est la première organisation mondiale qui élabore et publie des
Normes internationales pour tout ce qui a trait à l'électricité, à l'électronique et aux technologies apparentées.
A propos des publications IEC
Le contenu technique des publications IEC est constamment revu. Veuillez vous assurer que vous possédez l’édition la
plus récente, un corrigendum ou amendement peut avoir été publié.
Recherche de publications IEC - Le premier dictionnaire d'électrotechnologie en ligne au monde,
webstore.iec.ch/advsearchform avec plus de 22 000 articles terminologiques en anglais et en
La recherche avancée permet de trouver des publications IEC français, ainsi que les termes équivalents dans 16 langues
en utilisant différents critères (numéro de référence, texte, additionnelles. Egalement appelé Vocabulaire
comité d’études,…). Elle donne aussi des informations sur les Electrotechnique International (IEV) en ligne.
projets et les publications remplacées ou retirées.
Glossaire IEC - std.iec.ch/glossary
IEC Just Published - webstore.iec.ch/justpublished 67 000 entrées terminologiques électrotechniques, en anglais
Restez informé sur les nouvelles publications IEC. Just et en français, extraites des articles Termes et Définitions des
Published détaille les nouvelles publications parues. publications IEC parues depuis 2002. Plus certaines entrées
Disponible en ligne et une fois par mois par email. antérieures extraites des publications des CE 37, 77, 86 et
CISPR de l'IEC.
Service Clients - webstore.iec.ch/csc
Si vous désirez nous donner des commentaires sur cette
publication ou si vous avez des questions contactez-nous:
[email protected] .
Electropedia - www.electropedia.org
IEC 61123
Edition 2.0 2019-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Reliability testing – Compliance test plans for success ratio
Essais de fiabilité – Plans d'essai de conformité pour une proportion de succès
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 03.120.01; 03.120.30; 21.020 ISBN 978-2-8322-7647-1
– 2 – IEC 61123:2019 © IEC 2019
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 8
2 Normative references . 8
3 Terms, definitions, abbreviated terms and symbols . 8
3.1 Terms and definitions . 8
3.2 Abbreviated terms and symbols . 9
3.2.1 Abbreviated terms . 9
3.2.2 Symbols . 9
4 General requirements and area of application . 10
4.1 Reliability requirement . 10
4.2 Repair and replacement . 10
4.3 Types of test plans . 10
4.3.1 General . 10
4.3.2 Features of the test plan types. 10
4.4 General test procedure . 11
4.5 General decision criteria . 11
5 Truncated sequential probability ratio test plans (SPRT) . 13
5.1 Characteristics . 13
5.2 Decision criteria . 13
5.3 Operating characteristic curve (OC) . 14
5.4 Expected number of trials to decision (ENT) . 15
6 Fixed trial/failure terminated test plans (FTFT) . 16
6.1 Characteristics . 16
6.2 Decision criteria . 16
7 Design of fixed trial/failure terminated test plans . 17
7.1 Characteristics . 17
7.2 Approach . 17
7.3 Common case . 18
7.4 Other cases . 18
7.5 Example of application . 18
7.6 Procedure to determine D and c or n and c . 18
7.6.1 Figure and table readings . 18
7.6.2 Use of figures and tables . 19
7.7 Decision criteria . 19
Annex A (informative) Additional information on sequential test plans . 20
A.1 Example. 20
A.2 Extension of the test set (through interpolation and extrapolation) . 21
A.2.1 General . 21
A.2.2 Extrapolation for p < 0,001 . 21
A.2.3 Interpolation . 21
Annex B (informative) Design of fixed trial/failure terminated test plans − Examples . 24
B.1 Use of figures and tables . 24
B.2 Case where number of events, n, is not known, but is predictable . 24
Annex C (informative) Design of fixed trial/failure terminated test plans – Mathematical
procedures and formulas . 26
C.1 General . 26
C.2 Symbols . 26
C.3 Computation . 26
C.3.1 Determination of D versus n . 26
C.3.2 Determination of n and c versus p , D, α, β . 27
C.3.3 Test without failures – Determination of n and D versus p , α, β . 27
C.3.4 Determination of OC curves . 28
C.3.5 Determination of inverse OC curves . 28
C.4 Accuracy . 29
C.5 Tables of cumulative normal distribution and its Inverse. 29
Annex D (normative) Truncated sequential test plans . 31
Annex E (informative) Design of fixed trial/failure terminated test plans – Figures and
tables to determine D and c or n and c . 40
Bibliography . 49
Figure 1 – Expected and maximal number of trials for SPRT and FTFT with the same risks . 11
Figure 2 – SPRT diagram. 14
Figure 3 – OC curve. 15
Figure 4 – SPRT – Curve of expected number of trials to decision (ENT) . 15
Figure 5 – Principal layout of Tables E.1 to E.3 . 19
Figure A.1 – Example of a truncated sequential test . 20
Figure E.1 – Discrimination ratio, D, versus number of events, n for p = 0,05 . 40
Figure E.2 – Discrimination ratio, D, versus number of events, n for p = 0,10 . 41
Figure E.3 – Discrimination ratio, D, versus number of events, n for p = 0,15 . 42
Table 1 – Overview – Maximal number of trials and expected number of trials at p for
SPRT and FTFT . 12
Table 2 – Range of the test parameters . 13
Table 3 – OC curve . 14
Table 4 – ENT (n ) versus true failure ratio (p) .
...