IEC_61164-2004.pdf

INTERNATIONAL STANDARD IEC61164 Second edition2004-03 Reliability growth Statistical test and estimation methods Reference number IEC 61164:2004(E)LICENSED TO MECON Limited.-RANCHI/BANGALOREFOR INTERNAL USE AT THIS LOCATION ONLY,SUPPLIED BY BOOK SUPPLY BUREAU.Publication numberingAs from 1 January 1997 all IEC publications are issued with a designation in the60000 series.For example,IEC 34-1 is now referred to as IEC 60034-1.Consolidated editionsThe IEC is now publishing consolidated versions of its publications.For example,edition numbers 1.0,1.1 and 1.2 refer,respectively,to the base publication,thebase publication incorporating amendment 1 and the base publication incorporatingamendments 1 and 2.Further information on IEC publicationsThe technical content of IEC publications is kept under constant review by the IEC,thus ensuring that the content reflects current technology.Information relating tothis publication,including its validity,is available in the IEC Catalogue ofpublications(see below)in addition to new editions,amendments and corrigenda.Information on the subjects under consideration and work in progress undertakenby the technical committee which has prepared this publication,as well as the listof publications issued,is also available from the following:IEC Web Site(www.iec.ch)Catalogue of IEC publicationsThe on-line catalogue on the IEC web site(http:/www.iec.ch/searchpub/cur_fut.htm)enables you to search by a variety of criteria including text searches,technicalcommittees and date of publication.On-line information is also available onrecently issued publications,withdrawn and replaced publications,as well ascorrigenda.IEC Just Published This summary of recently issued publications(http:/www.iec.ch/online_news/justpub/jp_entry.htm)is also available by email.Please contact the CustomerService Centre(see below)for further information.Customer Service CentreIf you have any questions regarding this publication or need further assistance,please contact the Customer Service Centre:Email:custserviec.chTel:+41 22 919 02 11Fax:+41 22 919 03 00LICENSED TO MECON Limited.-RANCHI/BANGALOREFOR INTERNAL USE AT THIS LOCATION ONLY,SUPPLIED BY BOOK SUPPLY BUREAU.INTERNATIONAL STANDARD IEC61164 Second edition2004-03 Reliability growth Statistical test and estimation methods IEC 2004 Copyright-all rights reserved No part of this publication may be reproduced or utilized in any form or by any means,electronic or mechanical,including photocopying and microfilm,without permission in writing from the publisher.International Electrotechnical Commission,3,rue de Varemb,PO Box 131,CH-1211 Geneva 20,SwitzerlandTelephone:+41 22 919 02 11 Telefax:+41 22 919 03 00 E-mail:inmailiec.ch Web:www.iec.ch XA For price,see current cataloguePRICE CODE Commission Electrotechnique InternationaleInternational Electrotechnical Commission LICENSED TO MECON Limited.-RANCHI/BANGALOREFOR INTERNAL USE AT THIS LOCATION ONLY,SUPPLIED BY BOOK SUPPLY BUREAU.2 61164 IEC:2004(E)CONTENTS FOREWORD.4 INTRODUCTION.6 1 Scope.7 2 Normative references.7 3 Terms and definitions.7 4 Symbols.8 5 Reliability growth models in design and test.12 6 Reliability growth models used for systems/products in design phase.13 6.1 Modified power law model for planning of reliability growth in product design phase.13 6.2 Modified Bayesian IBM-Rosner model for planning reliability growth in design phase.16 7 Reliability growth planning a tracking in the product reliability growth testing.18 7.1 Continuous reliability growth models.18 7.2 Discrete reliability growth model.20 8 Use of the power law model in planning reliability improvement test programmes.23 9 Statistical test and estimation procedures for continuous power law model.23 9.1 Overview.23 9.2 Growth tests and parameter estimation.23 9.3 Goodness-of-fit tests.27 9.4 Confidence intervals on the shape parameter.29 9.5 Confidence intervals on current MTBF.31 9.6 Projection technique.33 Annex A(informative)Examples for planning and analytical models used in design and test phase of product development.37 Annex B(informative)The power law reliability growth model Background information.50 Bibliography.55 Figure 1 Planned improvement of the average failure rate or reliability.12 Figure A.1 Planned and achieved reliability growth Example.40 Figure A.2 Planned reliability growth using Bayesian reliability growth model.41 Figure A.3 Scatter diagram of expected and observed test times at failure based on data of Table A.2 with power law model.48 Figure A.4 Observed and estimated accumulated failures/accumulated test time based on data of Table A.2 with power law model.49 Table 1 Categories of reliability growth models with clause references.13 Table 2 Critical values for Cramr-von Mises goodness-of-fit test at 10%level of significance.34 Table 3 Two-sided 90%confidence intervals for MTBF from Type I testing.35 LICENSED TO MECON Limited.-RANCHI/BANGALOREFOR INTERNAL USE AT THIS LOCATION ONLY,SUPPLIED BY BOOK SUPPLY BUREAU