1、 IEC TR 61511-4 Edition 1.0 2020-02 TECHNICAL REPORT Functional safety Safety instrumented systems for the process industry sector Part 4:Explanation and rationale for changes in IEC 61511-1 from Edition 1 to Edition 2 IEC TR 61511-4:2020-02(en)THIS PUBLICATION IS COPYRIGHT PROTECTED Copyright 2020
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9、m the Terms and Definitions clause of IEC publications issued since 2002.Some entries have been collected from earlier publications of IEC TC 37,77,86 and CISPR.IEC TR 61511-4 Edition 1.0 2020-02 TECHNICAL REPORT Functional safety Safety instrumented systems for the process industry sector Part 4:Ex
10、planation and rationale for changes in IEC 61511-1 from Edition 1 to Edition 2 INTERNATIONAL ELECTROTECHNICAL COMMISSION ICS 13.110,ICS 25.040.01 ISBN 978-2-8322-7870-3 Registered trademark of the International Electrotechnical Commission Warning!Make sure that you obtained this publication from an
11、authorized distributor.2 IEC TR 61511-4:2020 IEC 2020 CONTENTS CONTENTS.2 FOREWORD.5 INTRODUCTION.7 1 Scope.8 2 Normative references.8 3 Terms,definitions and abbreviated terms.8 3.1 Terms and definitions.8 3.2 Abbreviated terms.9 4 Background.10 5 Management of functional safety(IEC 61511-1 Ed.2 Cl
12、ause 5).10 5.1 Why is this clause important?.10 5.2 Common misconceptions.10 5.3 What was changed from Ed.1 to Ed.2 and why?.11 5.3.1 Existing systems.11 5.3.2 Change management.11 5.3.3 Performance metrics and quality assurance.11 5.3.4 Competency.12 5.3.5 More requirements for functional safety pr
13、oduct and service providers.12 5.4 Summary on how.12 6 Safety life cycle(IEC 61511-1 Ed.2 Clause 6).12 6.1 Why is this clause important?.12 6.2 Common misconceptions.12 6.3 What was changed from Ed.1 to Ed.2 and why?.13 6.4 Summary on how.13 7 Verification(IEC 61511-1 Ed.2 Clause 7).13 7.1 Why is th
14、is clause important?.13 7.2 Common misconceptions.13 7.3 What was changed from Ed.1 to Ed.2 and why?.13 7.4 Summary on how.13 8 Hazard and risk analysis(IEC 61511-1 Ed.2 Clause 8).13 8.1 Why is this clause important?.13 8.2 Common misconceptions.14 8.3 What was changed from Ed.1 to Ed.2 and why?.14
15、8.4 Summary on how.15 9 Allocation of safety functions to protection layers (IEC 61511-1 Ed.2 Clause 9).15 9.1 Why is this clause important?.15 9.2 Common misconceptions.15 9.3 What was changed from Ed.1 to Ed.2 and why?.16 9.3.1 Limits on BPCS protection layers.16 9.3.2 Requirements for claiming RR
16、F 10 000 in total for instrumented safeguards.16 9.4 Summary on how.16 10 SIS safety requirements specification(IEC 61511-1 Ed.2 Clause 10).17 10.1 Why is this clause important?.17 10.2 Common misconceptions.17 10.3 What was changed from Ed.1 to Ed.2 and why?.18 IEC TR 61511-4:2020 IEC 2020 3 10.4 Summary on how.18 11 Design and engineering(IEC 61511-1 Ed.2 Clause 11).18 11.1 Why is this clause important?.18 11.2 Common misconceptions.18 11.3 What was changed from Ed.1 to Ed.2 and why?.19 11.3.1