1、BRITISH STANDARD BS QC 160000-2:1987 IEC255-10: 1979 Harmonized system ofquality assessment for electronic components Electrical relays Generic specification: Electromechanical all-or-nothing relays Part2: Quality assessment procedures IEC title: Electrical relays Part10: Application of the IEC Qual
2、ity Assessment System for Electronic Components to all-or-nothing relays UDC 621.318.5:620.16/.17:620.113BSQC160000-2:1987 This BritishStandard having been prepared under the direction of theElectronic Components Standards Committee, was published under the authority ofthe Board of BSI and comes int
3、o effect on 30October1987 BSI03-2000 The following BSI references relate to the work on this standard: Committee reference ECL/1 Draft for comment79/20638 DC ISBN 0 580 16193 5 Committees responsible for this BritishStandard The preparation of this BritishStandard was entrusted by the Electronic Com
4、ponents Standards Committee (ECL/-) to Technical Committee ECL/1, upon which the following bodies were represented: Association of Control Manufacturers TACMA (BEAMA Ltd.) British Telecommunications plc Electronic Components Industry Federation Ministry of Defence National Supervising Inspectorate T
5、elecommunication Engineering and Manufacturing Association (TEMA) Amendments issued since publication Amd. No. Date of issue CommentsBSQC160000-2:1987 BSI 03-2000 i Contents Page Committees responsible Inside front cover National foreword ii 1 Scope and object 1 2 Terms and definitions 1 3 Introduct
6、ion 1 4 Qualification approval procedure 1 5 Quality conformance inspection 2 6 Rules for sampling 2 7 Classification of relays 2 8 Guidelines for writing sectional specifications 3 9 Rules for the grouping of tests 3 10 Rules for writing detail specifications 4 Appendix A Rules for the grouping of
7、tests 5 Appendix B Test schedules 8 Appendix C Quality assessment procedures for short production runs, for isolated lots and for small lots 10 Appendix D Example of minimum test schedules for a detail specification of a d.c. relay with non-sealed contacts for contact application categories0 and1 11
8、 Table I Relay properties 3 Publications referred to Inside back coverBSQC160000-2:1987 ii BSI 03-2000 National foreword This Part of BS QC160000 has been prepared under the direction of the Electronic Components Standards Committee. It is identical with IECPublication255-10 “Electrical relays Part1
9、0: Application of the IEC Quality Assessment System for Electronic Components to all-or-nothing relays” published in1979 by the International Electrotechnical Commission (IEC). This standard is a harmonized specification within the IECQ system of quality assessment for electronic components. This Pa
10、rt and Part1 “Test and measurement procedures”, which is identical with IEC Publication255-7:1978, together constitute the generic specification for these components. IECQ is governed by its Basic Rules (IEC Publication QC001001) and its Rules of Procedure (IEC Publication QC001002). The UK standard
11、s harmonized with these publications are BS9000 “General requirements for a system for electronic components of assessed quality” Part1:1981 “Specification of basic rules and procedures” and Part3:1987 “Specification for national implementation of IECQ basic rules and rules of procedure”. This stand
12、ard and BS QC160000-1, used in conjunction with the relevant sectional and blank detail specifications, enable specification writers to prepare detail specifications for eletromechanical all-or-nothing relays. Terminology and conventions. The text of the International Standard has been approved as s
13、uitable for publication as a BritishStandard without deviation. Some terminology and certain conventions are not identical with those used in BritishStandards. Wherever the word “report” appears it should be read as “standard”. The Technical Committee has reviewed the provisions of IEC Publications5
14、0:Chapter446,410 and419, to which reference is made in the text, and has decided that they are acceptable for use in conjunction with this standard. Those parts of IEC Publication410 which are relevant to the needs of this standard are technically equivalent to BS6001-1:1972. A related BritishStanda
15、rd to IEC Publication50:Chapter446 is BS4727 “Glossary of electrotechnical, power, telecommunication, electronics, lighting and colour terms” Part1 “Terms common to power, telecommunications and electronics” Group03:1971 “Relay terminology”. At present there is no BritishStandard corresponding to IE
16、C Publication419. The International Standard refers to Documents CMC (Secretariat)35 and CMC(Secretariat)36. These have all now been incorporated in QC001001 and QC001002, and hence reference should be made to BS9000-1 and BS9000-3. Cross-references International Standard a Corresponding BritishStan
17、dard IEC255-7:1978 BS QC160000 Harmonized system of quality assessment for electrical components. Electrical relays. Generic specification: Electromechanical all-or-nothing relays Part1:1987 Test and measurement procedures (Identical) a Undated in the text.BSQC160000-2:1987 BSI 03-2000 iii A British
18、 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 of pages This document comprises a front c
19、over, an inside front cover, pagesi to iv, pages1to12, 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.iv blankBSQC160000-2:1987 BSI 03-2000 1
20、1 Scope and object This report applies to all-or-nothing relays. It provides guidelines for: a) qualification and quality conformance procedures; b) the classification of relays; c) the grouping of tests; d) making test schedules; e) the application of the Itemsa),b),c) andd) in preparing sectional
21、documents and detail specifications. These guidelines are intended to be used within the IEC quality assessment system. 2 Terms and definitions Reference should be made to the other IEC publications of the255 series and to the International Electrotechnical Vocabulary (I.E.V.) (IEC Publication50), C
22、hapter446. 3 Introduction The basic concept of the IEC quality assessment system is to provide assurance to the purchasers that the relays which are released conform to the requirements in the detail specifications. All the tests shall be conducted under the responsibility of the chief inspector nom
23、inated by the manufacturer. 1) The procedures comprise the following consecutive basic steps: a) qualification approval; b) quality conformance inspection. For relays manufactured in small quantities, in isolated lots, or in short production runs, special procedures are applicable (seeAppendix C). F
24、or each test in the test schedule, the detail specification shall indicate whether the test has to be carried out as part of the qualification approval tests, as part of the lot-by-lot inspection, or as part of the periodic inspection. Where any discrepancies occur for any reason, documents shall ra
25、nk in the following order of authority: 1) the customers contractual requirements; 2) the detail specification; 3) the generic specification; 4) the basic rules documents applying to the quality assurance scheme. The same order of precedence shall apply to equivalent national documents. 4 Qualificat
26、ion approval procedure The qualification approval tests of a relay-type are the complete series of tests to be carried out on a number of relays, with the object of determining whether a particular manufacturer can be considered capable of producing relays meeting the detail specification. The quali
27、fication approval tests comprise all the tests indicated in the detail specification including the lot-by-lot and periodic tests. Qualification approval shall be based on conformance with the requirements of the qualification approval tests only and: Method1: For short production runs the conformanc
28、e with the requirements of the test specifically prescribed in the detail specification for this purpose. Method2: For continuous production and large production runs the conformance with the requirements of the tests in the detail specification achieved for three consecutive lots subjected to lot-b
29、y-lot inspection for Groups A and B tests and on a lot (drawn from the three accepted lots) subjected to the Group C periodic inspection (using the average lot size for the three lot-by-lot inspections to determine the sample size). The samples shall be taken from the lots according to IEC Publicati
30、on410, Sampling Plans and Procedures for Inspection by Attributes. 1) At the time of printing. Clauses9, 10 and11 of Documents CMC(Secretariat)35 and36 were under consideration.BSQC160000-2:1987 2 BSI 03-2000 Normal inspection shall be used, but where the sample size would give acceptance on zero de
31、fectives, additional specimens shall be taken to meet the sample size required to give acceptance on one or more defectives. When Method1 is applied, the detail specification shall state the sample size and the associated permissible number of defectives, together with the amount of endurance testin
32、g. These shall pay due regard to the limiting quality of the sampling plan to be used and shall be as agreed between manufacturer and purchaser. NOTESince the confidence in the results of the qualification approval tests is not only derived from the statistical inferences but also is based on the ov
33、erall technical information and taking into account the costs involved in qualification approval testing, the detail specification may select the smallest possible sample sizes within the rules. The sample sizes and accept/reject numbers shall be selected from the sampling plans given in IECPublicat
34、ion410 and as a general rule the sample size shall not be less than5 for any group of tests. 5 Quality conformance inspection After qualification approval has been obtained the manufacturer is responsible for ensuring that no major technical changes are introduced for the product without re-qualific
35、ation being made and that the quality conformance inspection prescribed by the specification is carried out. This inspection is divided into two parts: That carried out lot by lot and on which the release of the individual lots is based. That (containing the time-consuming and more expensive tests)
36、carried out on a periodic basis. Quality conformance inspection is based on conformity with the requirements of the tests mentioned in the detail specifications as lot-by-lot tests and periodic tests. Tests in sub-group A0 (seeAppendix A) should always precede all other non-destructive tests. Tests
37、in sub-group A0 should always precede all destructive tests. Each test shall be conducted on a relay not previously subjected to any destructive or non-destructive test liable to invalidate the result of the test being undertaken. Otherwise, subject to any specific restrictions given in the detail s
38、pecification, a destructive test may be preceded by one or more non-destructive tests. 6 Rules for sampling Sampling shall be carried out in accordance with the sampling plans and procedures given in IECPublication410, using per cent defective concept only. The inspection levels specified in the sec
39、tional documents shall be selected in accordance with Sub-clause9.2 of IEC Publication410. For each particular sub-group, the same inspection level is used in all the different test schedules. The standard inspection levels will apply normally but higher levels can be specified where greater confide
40、nce is required in the conformance. For each test in a sub-group, a random sample shall be taken in accordance with the sampling plan obtained from IEC Publication410 for the inspection level and acceptable quality level prescribed for that sub-group. Stratified sampling should always be used to inc
41、lude all production lines and structurally similar items in proportion to their respective quantities in the lot. Samples for Group C inspection shall be taken from a lot (or lots) which has (have) passed Groups A and B inspection. They can be taken either from the lot which leaves production at the
42、 end of the Group C period or from differents lots at intervals during the Group C period. In either case, the sample size shall be not less than that applicable to the average lot size in the current Group C period. Specimens should be as representative as possible of the production. 7 Classificati
43、on of relays Various attempts to classify relays solely by type, technology, application or use, have proved abortive due to similarities and interdependence in their various characteristics and this report classifies relays according to different test schedules; these schedules are based on experie
44、nce and are characterized by the number of mandatory tests in the schedule and their distribution over the various sub-groups. The rules for grouping of tests are given in Clause9 and in Appendix A. The test schedules constructed according to the rules for grouping of tests can be found in Appendix
45、B.BSQC160000-2:1987 BSI 03-2000 3 In test schedule1 the number of mandatory tests is limited. In test schedules2 and3 there is an increase in the number of mandatory tests. 8 Guidelines for writing sectional specifications Three sectional specifications can be prepared, each using one of the test sc
46、hedules. Each sectional specification can then be used as a guide in writing detail specifications. The sectional specification contains proposals for the inspection levels and preferred acceptable quality level values for each test. The test schedules take account of the technology of the relay and
47、 of the contact application by indicating the applicability with respect to technology and contact application. The most general categories of technology and contact application are given in Table I. This table shall form part of the sectional document. When the characteristics of the contact cannot
48、 be classified in one or more of the stated categories, or when particular tests are required, the detail specification shall give the necessary indications. The detail specification shall state the relevant properties chosen from this table. Table I Relay properties 9 Rules for the grouping of test
49、s 9.1 Principles adopted The purpose of grouping of tests is to combine in one group all those tests which are of equal importance to the assessment of the usefulness of the relay. Therefore each test in the same sub-group gets the same inspection level and acceptable quality level range and therefore further criteria for the allocation of tests to a group are the destructiveness of the test, the duration of the test, and the relation to fabrication or design. The frequency of testing takes account of the complexity, duration and overall cost of the test and the