1、BRITISH STANDARD BS IEC 61225:2005 Nuclear power plants Instrumentation and control systems important to safety Requirements for electrical supplies ICS 27.120.20 BS IEC 61225:2005 This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 January 20
2、06 BSI 31 January 2006 ISBN 0 580 47629 4 National foreword This British Standard reproduces verbatim IEC 61225:2005 and implements it as the UK national standard. It supersedes BS 7674:1993 which is withdrawn. The UK participation in its preparation was entrusted to Technical Committee NCE/8, React
3、or instrumentation, which has the responsibility to: aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep UK interests informed; monitor related international and European developments
4、 and promulgate them in the UK. A list of organizations represented on this committee can be obtained on request to its secretary. Cross-references The British Standards which implement international publications referred to in this document may be found in the BSI Catalogue under the section entitl
5、ed “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online. This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. Compliance
6、with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, the IEC title page, The BSI copyright notice displayed in this document indicates when the document was last issued. Amendments issued sin
7、ce publication Amd. No. Date Comments pages 2 to 32, an inside back cover and a back cover. CEI IECINTERNATIONAL STANDARD 61225 Second edition 2005-12Nuclear power plants Instrumentation and control systems important to safety Requirements for electrical supplies Reference number CEI/IEC 61225:2005
8、CONTENTS 0 Introduction . 6 1 Scope 8 2 Normative references 8 3 Terms and definitions 9 4 System requirements . 10 4.1 Function and description 10 4.2 System divisions 10 4.3 System boundaries . 10 5 Requirements for redundancy, physical separation, and independence . 11 5.1 General 11 5.2 Redundan
9、cy . 11 5.3 Physical separation 11 5.4 Independence 11 5.5 Reliability . 12 6 Functional requirements for I any IEC National Committee interested in the subject dealt with may participate in this preparatory work. International, governmental and non- governmental organizations liaising with the IEC
10、also participate in this preparation. IEC collaborates closely with the International Organization for Standardization (ISO) in accordance with conditions determined by agreement between the two organizations. 2) The formal decisions or agreements of IEC on technical matters express, as nearly as po
11、ssible, an international consensus of opinion on the relevant subjects since each technical committee has representation from all interested IEC National Committees. 3) IEC Publications have the form of recommendations for international use and are accepted by IEC National Committees in that sense.
12、While all reasonable efforts are made to ensure that the technical content of IEC Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any misinterpretation by any end user. 4) In order to promote international uniformity, IEC National Committees underta
13、ke to apply IEC Publications transparently to the maximum extent possible in their national and regional publications. Any divergence between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter. 5) IEC provides no marking procedure to i
14、ndicate its approval and cannot be rendered responsible for any equipment declared to be in conformity with an IEC Publication. 6) All users should ensure that they have the latest edition of this publication. 7) No liability shall attach to IEC or its directors, employees, servants or agents includ
15、ing individual experts and members of its technical committees and IEC National Committees for any personal injury, property damage or other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and expenses arising out of the publication, use of, or relian
16、ce upon, this IEC Publication or any other IEC Publications. 8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is indispensable for the correct application of this publication. 9) Attention is drawn to the possibility that some of the ele
17、ments of this IEC Publication may be the subject of patent rights. IEC shall not be held responsible for identifying any or all such patent rights. International Standard IEC 61225 has been prepared by subcommittee 45A: Instrumentation and control of nuclear facilities, of IEC technical committee 45
18、: Nuclear instrumentation. This second edition cancels and replaces the first edition published in 1993. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition: a) general update of all the references in C
19、lause 2 and throughout the text of this standard; b) addition of references to IEC 62138, IEC 61513, and IEC 60880; 4 BS IEC 61225:2005 c) addition of software programme design, categorization, verification, and validation requirements; d) addition of the recommendation to avoid parallel connection
20、of batteries from more than one division; e) addition of the requirement that, when batteries are connected in parallel under abnormal operating conditions, they shall be properly protected with isolation devices to avoid any failure that may impair more than one division; f) editorial changes throu
21、ghout the standard to improve comprehension and clarity; g) correction of minor errors in Figures 1, 4, and 5; h) addition of more typical performance characteristics to the examples in Annex A for reference purposes, adherence to these values being at the discretion of the users. The text of this s
22、tandard is based on the following documents: FDIS Report on voting 45A/595/FDIS 45A/602/RVD Full information on the voting for the approval of this standard can be found in the report on voting indicated in the above table. This publication has been drafted in accordance with the ISO/IEC Directives,
23、 Part 2. The committee has decided that the contents of this publication will remain unchanged until the maintenance result date indicated on the IEC web site under “http:/webstore.iec.ch“ in the data related to the specific publication. At this date, the publication will be reconfirmed; withdrawn;
24、replaced by a revised edition, or amended. 5 BS IEC 61225:2005 0 Introduction 0.1 Technical background, main issues and organization of the standard The 1993 issue of IEC 61225 was developed for specifying the requirements relevant to the design of electrical supplies of nuclear power plants. Consid
25、ering the experience gathered worldwide on this subject, in 2003 the working group A2 recommended a revision to this standard so that this revision, IEC 61225 Ed. 2 (2005), be consistently integrated into the SC 45A standard series. This standard is applicable to the design of electrical supplies of
26、 new nuclear power plants, whose design work is initiated after the publication of this standard. It also serves as a reference for upgrading and modernizing existing nuclear power plants. 0.2 Situation of the current standard in the structure of the SC 45A standard series IEC 61225 is the third-lev
27、el document specifically tackling the particular topic of requirements for electrical supplies. For more details on the structure of the SC 45A standard series, see Clause 0.4. 0.3 Recommendations and limitations regarding the application of this standard This standard is to be applied in conjunctio
28、n with IEC 61513, IEC 61226, IEC 60709, IEC 60880 and IEC 62138. 0.4 Description of the structure of the SC 45A standard series and relationships with other IEC documents and documents from other bodies (IAEA, ISO) The top-level document of the SC 45A standard series is IEC 61513. It provides genera
29、l requirements for instrumentation and control systems and equipment (I&C systems) that are used to perform functions important to safety in nuclear power plants (NPPs) and structures the SC 45A standard series. IEC 61513 refers directly to other SC 45A standards for general topics related to catego
30、rization of functions and classification of systems, qualification, separation of systems, defence against common-cause failure, software aspects of computer-based systems, hardware aspects of computer-based systems, and control-room design. The standards referenced directly at this second level sho
31、uld be considered together with IEC 61513 as a consistent document set. At a third level, SC 45A standards not directly referenced by IEC 61513 are standards related to specific equipment, technical methods or activities. Usually these documents, which make reference to second-level documents for ge
32、neral topics, can be used on their own. A fourth level extending the SC 45A standard series corresponds to the technical reports which are not normative. BS IEC 61225:2005 6 IEC 61513 has adopted a presentation format similar to that of IEC 61508, with an overall safety life-cycle framework and a sy
33、stem life-cycle framework, and provides an interpretation of the general requirements of IEC 61508-1, IEC 61508-2 and IEC 61508-4, for the nuclear application sector. Compliance with IEC 61513 facilitates consistency with the requirements of IEC 61508 as they have been interpreted for the nuclear in
34、dustry. In this framework, IEC 60880 and IEC 62138 correspond to IEC 61508-3 for the nuclear application sector. IEC 61513 refers to ISO as well as to IAEA 50-C-QA for topics related to quality assurance. The SC 45A standards series consistently implements and details the principles and basic safety
35、 aspects provided in the IAEA Code on the safety of nuclear power plants and in the IAEA safety series, in particular NS-R-1 and the Safety Guide NS-G-1.3. The terminology and definitions used by SC 45A standards are consistent with those used by the IAEA. BS IEC 61225:2005 7 NUCLEAR POWER PLANTS IN
36、STRUMENTATION AND CONTROL SYSTEMS IMPORTANT TO SAFETY REQUIREMENTS FOR ELECTRICAL SUPPLIES 1 Scope This International Standard specifies the performance and the functional characteristics of the electrical supply systems required for the instrumentation and control (I&C) systems important to safety
37、of a nuclear power plant. Guidance is also given on the possible use of these supplies for other I&C systems. These supplies should be fed from primary sources of suitable redundancy and reliability, so that the safety and functional objectives of the I&C system can be adequately achieved. This stan
38、dard defines the methods of application of IAEA Safety Guide NS-G-1.3. The specific design requirements for the components of the I&C power supply system are covered by IEC standards and standards listed in the references and are otherwise outside the scope of this standard. The scope of the I&C pow
39、er supply system covered by this standard does not apply to supplies to certain equipment within an I&C system, which may need specific and special quality or reliability of power supplies, such as closer tolerances of frequency or voltage or of interruption time for loss of supply shorter than the
40、period required by the normal tolerances of IEC standards relevant to power plants. 2 Normative references 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 th
41、e referenced document (including any amendments) applies. IEC 60038:2002, IEC standard voltages IEC 60146-2:1999, Semiconductor converters Part 2: Self-commutated semiconductor converters including direct d.c. converters IEC 60686:1980, Stabilized power supplies, a.c. output IEC 60709, Nuclear power
42、 plants Instrumentation and control systems important to safety Separation IEC 60780:1998, Nuclear power plants Electrical equipment of the safety system Qualification IEC 60880, Software for computers in the safety of nuclear power plants BS IEC 61225:2005 8 IEC 60980:1989, Recommended practices fo
43、r seismic qualification of electrical equipment of the safety system for nuclear generating stations IEC 61000-4, Electromagnetic compatibility (EMC) Part 4: Testing and measurement techniques IEC 61226, Nuclear power plants Instrumentation and control systems important to safety Classification of i
44、nstrumentation and control functions IEC 61513, Nuclear power plants Instrumentation and control for systems important to safety General requirements for systems IEC 62138, Nuclear power plants Instrumentation and control systems important to safety Software aspects for computer-based systems perfor
45、ming category B or C functions IAEA Safety Guide NS-G-1.3: Instrumentation and control systems important to safety in nuclear power plants 3 Definitions For the purposes of this document, the following definitions apply. Other terms not defined below are defined in IAEA Safety Guide NS-G-1.3. 3.1 it
46、em important to safety item that is part of a safety group and/or whose malfunction or failure could lead to radiation exposure of the site personnel or members of the public Derived from IAEA Safety Guide NS-G-1.3 3.2 safety system system important to safety, provided to ensure the safe shutdown of
47、 the reactor or residual heat removal from the core, or to limit the consequences of anticipated operational occurrences and design basis accidents IAEA Safety Guide NS-G-1.3 3.3 safety-related I&C system I&C system important to safety which is not part of a safety system IAEA Safety Guide NS-G-1.3 3.4 safety system support features collection of equipment that provides services such as cooling, lubrication and energy supply required by the protection system and the safety actuation systems IAEA Safety Guide NS-G-1.3 BS IEC 61225:2005 9