1、BRITISH STANDARD BS 5760-10.5: 1993 IEC 1123:1991 Reliability of systems, equipment and components Part 10: Guide to reliability testing Section 10.5 Compliance test plans for success ratioBS5760-10.5:1993 This British Standard, having been prepared under the directionof the Quality, Management and
2、Statistics Standards Policy Committee, waspublished under the authorityof the Standards Boardand comes into effect on 15November1993 BSI 12-1999 The following BSI references relate to the work on this standard: Committee reference QMS/23 Special announcement in BSINews, March1993 ISBN 0 580 22584 4
3、Committees responsible for this British Standard The preparation of this British Standard was entrusted by the Quality, Management and Statistics Standards Policy Committee (QMS/-) to Technical Committee QMS/23, upon which the following bodies were represented: AEA Technology Association of Consulti
4、ng Engineers Association of Project Managers British Gas plc British Railways Board British Telecommunications plc City University Civil Aviation Authority Consumers Association Cranfield Institute of Technology Department of Trade and Industry (Standards Policy Unit) Design Council EEA (the Associa
5、tion of Electronics, Telecommunications and Business Equipment Industries) Electricity Association Electronic Components Industry Federation Federation of Small Businesses GAMBICA (BEAMA Ltd.) Institute of Quality Assurance Institute of Risk Management Institution of Electrical Engineers Institution
6、 of Mechanical Engineers Institution of Plant Engineers Mercury Communications Limited Ministry of Defence National Computing Centre Ltd. Railway Industry Association of Great Britain Royal Institution of Chartered Surveyors Safety and Reliability Society Society of British Aerospace Companies Limit
7、ed Society of Environmental Engineers Society of Motor Manufacturers and Traders Limited University of Technology, Loughborough Amendments issued since publication Amd. No. Date CommentsBS5760-10.5:1993 BSI 12-1999 i Contents Page Committees responsible Inside front cover National foreword ii 1 Scop
8、e 1 2 Normative references 1 3 Other references 1 4 Definitions 1 5 List of symbols 1 6 Application 2 7 General decision criteria 2 8 Truncated sequential test plans 3 9 Fixed trial/failure terminated test plans 7 10 Design of trial or failure terminated test plans 9 Annex A (informative) Additional
9、 information on sequential test plans 23 Annex B (informative) Design of trial or failure terminated test plansExamples 24 Annex C (informative) Designed trial or failure terminated test plansMathematical procedures and formulas 25 Figure 1 Truncated sequential test 3 Figure 2 OC curve 4 Figure 3 Cu
10、rve of expected number of trials 5 Figure 4 Principal layout of Table 3 toTable 5 10 Figure 5 Discrimination ratio, D, versus number of events, n 11 Figure 6 Discrimination ratio, D, versus number of events, n 12 Figure 7 Discrimination ratio, D, versus number of events, n 13 Figure A.1 Example of a
11、 truncated sequential test 23 Table 1 Truncated sequential tests 6 Table 2 Tests with fixed number of trials 8 Table 3 Acceptable number of failures, c, versus number of events, n 14 Table 4 Acceptable number of failures, c, versus number of events, n 17 Table 5 Acceptable number of failures, c, ver
12、sus number of events, n 20 Table C.1 Cumulative normal distribution for fixed u values 27 Table C.2 Inverse cumulative normal distribution for fixed1 values 27 List of references Inside back coverBS5760-10.5:1993 ii BSI 12-1999 National foreword This Part of BS5760 has been prepared under the direct
13、ion of the Quality, Management and Statistics Standards Policy Committee. It is identical with IEC1123:1991 Reliability testingCompliance test plans for success ratio published by the International Electrotechnical Commission (IEC). BS5760 provides comprehensive guidance on many aspects of reliabili
14、ty management. Eleven Parts of this standard have been published and these may be summarized as follows: Part0: Introductory guide to reliability. This Part provides guidance to senior management and non-specialists on the importance of reliability and explains how measures to achieve reliability sh
15、ould be integrated with other aspects of project management. Part1: Guide to reliability and maintainability programme management. This Part discusses the essential features of a comprehensive reliability and maintainability programme to produce reliable and maintainable products. Part2: Guide to th
16、e assessment of reliability. This Part contains guidance on quantitative and statistical aspects of reliability, including reliability modelling, the provision of data, and the concepts of redundancy and simulation. Part3: Guide to reliability practices: examples. This Part contains authentic practi
17、cal examples illustrating the principles established in Parts1 and 2 of BS5760. Part4: Guide to specification clauses relating to the achievement and development of reliability in new and existing items. This Part provides detailed guidance on the specification of reliability. Part5: Guide to failur
18、e modes, effects and criticality analysis (FMEA) and (FMECA). This Part gives guidance on the application of these techniques. Part6: Guide to programmes for reliability growth. This Part describes procedures to expose and remove weaknesses in hardware and software items in order to achieve acceptab
19、le reliability in a product. It explains basic concepts, management and test procedures and describes techniques for analysis and correction of failures. Part7: Guide to fault tree analysis. This Part gives guidance on the application of fault tree analysis which may be used to identify factors affe
20、cting the reliability, performance and safety characteristics of a system. Part9: Guide to the block diagram technique. This Part describes the use of the block diagram technique for modelling and evaluating the reliability of both elementary and more complex systems. The extension of the method to
21、calculate availability is also outlined. Part10: Guide to reliability testing: Section10.1: General requirements. This Section provides guidance on general principles, procedures and considerations for reliability testing in the laboratory and in the field. Section10.3: Compliance test procedures fo
22、r steady-state availability. ThisSection provides guidance on techniques for testing the availability performance of frequently maintained items under defined conditions. Section10.5: Compliance test plans for success ratio. This Section gives procedures for preparing and applying compliance test pl
23、ans for success ratio or failure ratio. Plans are provided for three main types of test. Part12: Guide to the presentation of reliability, maintainability and availability predictions. This Part gives guidance on the presentation of quantitative predictions of reliability, maintainability and availa
24、bility. The items to be included when presenting prediction information are listed and explained with the object of facilitating comparisons between projects and reports.BS5760-10.5:1993 BSI 12-1999 iii Part14: Guide to formal design review. This Part provides guidelines for planning and conducting
25、design reviews. It includes details of the specific contributions to be made by various specialists but much of the guidance given is widely applicable and is relevant to the general conduct of design reviews. Further Parts of BS5760 are envisaged in order to provide guidance on other techniques of
26、reliability management. At present three further Parts are in the process of being drafted, and these are as follows: Part8: Guide to the assessment of reliability of systems containing software. This Part will provide guidance on the assessment of reliability of systems containing software. (This i
27、s currently published as DD198:1991.) Part11: Guide to the collection of reliability, maintainability, availability and maintenance support data from the field. Part13: Guide to preferred test conditions for equipment reliability testing. Further Sections of Part10 based on other Parts of IEC605 and
28、 related IEC standards are also planned. Guidance on specific aspects of maintainability is provided in the various Parts of BS6548 Maintainability of equipment. The Technical Committee has reviewed the provisions of IEC410, to which reference is made in the text, and has decided that they are accep
29、table for use in conjunction with this standard. Cross-references International Standard Corresponding British Standard IEC50(191):1990 BS4778 Quality vocabulary Part3 Availability, reliability and maintainability terms Section3.2:1991 Glossary of international terms (Identical) IEC605-1:1978 BS5760
30、 Reliability of systems, equipment and components Part10 Guide to reliability testing Section10.1:1993 General requirements (Identical) ISO3534:1977 BS5532 Statistical terminology Part1:1978 Glossary of terms relating to probability andgeneral terms relating to statistics (Identical)BS5760-10.5:1993
31、 iv BSI 12-1999 Textual error. When adopting the text of the International Standard, the textual error given below was discovered. It has been marked in the text and has been reported to IEC in a proposal to amend the text of the International Standard. In Table 1, for q 0 =0,930, D =1.75 and =20%,
32、the value of n tshould be“143”. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary o
33、f pages This document comprises a front cover, an inside front cover, pagesi toiv, pages1to28, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover.
34、BS5760-10.5:1993 BSI 12-1999 1 1 Scope This International Standard specifies procedures for applying and preparing compliance test plans for success ratio or failure ratio. The procedures are based on the assumption that each trial is statistically independent. 2 Normative references The following s
35、tandards contain provisions which, through reference in this text, constitute provisions of this International Standard. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this International Standard are encouraged
36、 to investigate the possibility of applying the most recent editions of the standards listed below. Members of IEC and ISO maintain registers of currently valid International Standards. IEC50(191):1990, International Electrotechnical VocabularyChapter191: Dependability and quality ofservice. IEC605-
37、1:1978, Equipment reliability testingPart1: General requirements. Amendment1 (1982). 3 Other references IEC410:1973, Sampling plans and procedures for inspection by attributes. ISO3534:1977, StatisticsVocabulary and symbols. 4 Definitions Terms and definitions are in accordance with IEC50(191). In a
38、ddition, the following definitions are applicable for this International Standard: 4.1 success ratio the probability that an item will perform a required function or that a trial will be successful under stated conditions NOTEAn observed success ratio is the ratio of the number of non-faulty items o
39、r of successful trials at the completion of testing, to the total number of test items or number of trials. 4.2 failure ratio the probability that an item will fail or that a trial will be unsuccessful under stated conditions NOTEAn observed failure ratio is the ratio of the number of faulty items o
40、r of unsuccessful trials at the completion of testing, to the total number of test items or number of trials. 5 List of symbols ! nominal producers risk (type I risk) ! true producers risk (type I risk) “ nominal consumers risk (type II risk) “ true consumers risk (type II risk) c acceptable number
41、of failures or unsuccessful events during the test NOTEr RE , number of failures for rejection in IEC605-5, first edition (1982), corresponds to c +1. D nominal discrimination ratio, D = p 1 /p 0 =(1q 1 )/(1q 0 ) NOTED Ris the corresponding symbol in IEC605-5, first edition (1982). D true discrimina
42、tion ratio h intercept values of the accept and reject lines on the vertical axis of the sequential test diagram (seeFigure 1) n number of items, number of trials, number of events, sample size n f number of items, number of trials, number of events, sample size required for acceptance n s accumulat
43、ed number of trials in a sequential test planBS5760-10.5:1993 2 BSI 12-1999 6 Application 6.1 Reliability requirement The requirement is assumed to be specified as: acceptable failure ratio, p 0or acceptable success ratio, q 0(p 0 =1q 0 ). These test plans are based on the assumption that each trial
44、 is statistically independent and that the probability of success (or failure) is constant, i.e.the binomial distribution assumptions apply. The true producers and consumers risks for the test plans differ from the nominal characteristics ! and “ due to the necessary approximations to whole numbers
45、and to the truncation of the sequential tests. 6.2 Repair and replacement The test plans given in this standard are applicable to reused as well as non-reused (one-shot) items. Reused items may be repaired between successive trials, provided that the state and performance are the same at the start o
46、f all trials. For non-reused items, a separate test item is used for each trial. 6.3 Types of test plans Test plans are given for three types of tests: truncated sequential tests (seeclause8); fixed trial/failure terminated tests (seeclause9); designed trial/failure terminated tests (seeclause10). T
47、he detailed reliability test specification shall state which type of test and which test plan are to be used. Guidance for the choice of type of test is similar to that given in IEC605-1, 7.3.1, for truncated sequential and time/failure terminated tests for the case in which the reliability measure
48、is a function of time. 6.4 General test procedure The test items shall be subjected to the number of trials according to the relevant test plan. For reused, replaced or repaired items, the detailed reliability test specifications should preferably state the number of test items as well as the maximu
49、m number of trials for each test item. A trial is defined as the operation or cycle as described in the detailed reliability test specification. 7 General decision criteria All test plans and decision criteria are based on either: an acceptable number of relevant failures for a specified number of trials; or an acceptable number of trials for a specified number of relevant failures. The numbers of trials and relevant failures (seeIEC605-1, 9.2) are counted and compared with the decision criteria of the test
