IEC 61784-3:2021

Industrial communication networks - Profiles - Part 3: Functional safety fieldbuses - General rules and profile definitions

IEC 61784-3:2021 explains some common principles that can be used in the transmission of safety-relevant messages among participants within a distributed network which use fieldbus technology in accordance with the requirements of IEC 61508 (all parts) for functional safety. These principles are based on the black channel approach. They can be used in various industrial applications such as process control, manufacturing automation and machinery.

Réseaux de communication industriels - Profils - Partie 3: Bus de terrain de sécurité fonctionnelle - Règles générales et définitions de profils

L'IEC 61784-3:2021 définit des principes communs qui peuvent être appliqués pour la transmission des messages relatifs à la sécurité entre les participants d'un réseau réparti, à l'aide de la technologie de bus de terrain conformément aux exigences de l'IEC 61508 (toutes les parties) sur la sécurité fonctionnelle. Ces principes s'appuient sur le principe de canal noir. Ils peuvent être utilisés dans différentes applications industrielles, par exemple la commande de processus, l'usinage automatique et les machines.

General Information

• Status: Published
• Publication Date: 18-Apr-2024
• ICS: 25.040.40 - Industrial process measurement and control
• ICS: 35.100.05 - Multilayer applications
• Technical Committee: SC 65C - Industrial networks
• Drafting Committee: WG 12 - TC 65/SC 65C/WG 12
• Current Stage: PPUB - Publication issued
• Start Date: 25-Jan-2021
• Completion Date: 16-Feb-2021

Relations

• Amended By: IEC 61784-3:2021/AMD1:2024 - Amendment 1 - Industrial communication networks - Profiles - Part 3: Functional safety fieldbuses - General rules and profile definitions
• Effective Date: 05-Sep-2023
• Revises: IEC 61784-3:2016/AMD1:2017 - Amendment 1 - Industrial communication networks - Profiles - Part 3: Functional safety fieldbuses - General rules and profile definitions
• Effective Date: 05-Sep-2023
• Revises: IEC 61784-3:2016 - Industrial communication networks - Profiles - Part 3: Functional safety fieldbuses - General rules and profile definitions
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 61784-3 ®
Edition 4.1 2024-04
CONSOLIDATED VERSION
INTERNATIONAL
STANDARD
colour
inside
Industrial communication networks – Profiles –
Part 3: Functional safety fieldbuses – General rules and profile definitions

All rights reserved. Unless otherwise specified, 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
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IEC 61784-3 ®
Edition 4.1 2024-04
CONSOLIDATED VERSION
INTERNATIONAL
STANDARD
colour
inside
Industrial communication networks – Profiles –
Part 3: Functional safety fieldbuses – General rules and profile definitions
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 25.040.40, 35.100.05 ISBN 978-2-8322-8373-8
REDLINE VERSION – 2 – IEC 61784-3:2021+AMD1:2024 CSV
© IEC 2024
CONTENTS
FOREWORD . 7
0 Introduction . 9
0.1 General . 9
0.2 Use of extended assessment methods in Edition 4 . 11
0.3 Patent declaration . 11
INTRODUCTION to Amendment 1 . 12
1 Scope . 13
2 Normative references . 13
3 Terms, definitions, symbols, abbreviated terms and conventions . 15
3.1 Terms and definitions . 15
3.2 Symbols and abbreviated terms . 22
3.2.1 Abbreviated terms . 22
3.2.2 Symbols . 23
4 Conformance . 23
5 Basics of safety-related fieldbus systems . 24
5.1 Safety function decomposition . 24
5.2 Communication system . 25
5.2.1 General . 25
5.2.2 IEC 61158 fieldbuses . 25
5.2.3 Communication channel types . 25
5.2.4 Safety function response time . 26
5.3 Communication errors . 26
5.3.1 General . 26
5.3.2 Corruption . 26
5.3.3 Unintended repetition . 27
5.3.4 Incorrect sequence . 27
5.3.5 Loss . 27
5.3.6 Unacceptable delay . 27
5.3.7 Insertion . 27
5.3.8 Masquerade. 27
5.3.9 Addressing . 27
5.4 Deterministic remedial measures . 28
5.4.1 General . 28
5.4.2 Sequence number. 28
5.4.3 Time stamp . 28
5.4.4 Time expectation . 28
5.4.5 Connection authentication . 28
5.4.6 Feedback message . 28
5.4.7 Data integrity assurance . 28
5.4.8 Redundancy with cross checking . 29
5.4.9 Different data integrity assurance systems .
5.5 Typical relationships between errors and safety measures . 29
5.6 Communication phases . 30
5.7 FSCP implementation aspects . 31
5.8 Models for estimation of the total residual error rate . 32
5.8.1 Applicability . 32

© IEC 2024
5.8.2 General models for black channel communications . 32
5.8.3 Identification of generic safety properties . 33
5.8.4 Assumptions for residual error rate calculations . 33
5.8.5 Residual error rates . 34
5.8.6 Data integrity . 36
5.8.7 Authenticity. 37
5.8.8 Timeliness . 39
5.8.9 Masquerade. 42
5.8.10 Calculation of the total residual error rates . 42
5.8.11 Total residual error rate and SIL . 44
5.8.12 Configuration and parameterization for an FSCP . 44
5.9 Relationship between functional safety and security . 46
5.10 Boundary conditions and constraints . 46
5.10.1 Electrical safety . 46
5.10.2 Electromagnetic compatibility (EMC) . 47
5.11 Installation guidelines . 47
5.12 Safety manual . 47
5.13 Safety policy . 48
6 Communication Profile Family 1 (FOUNDATION™ Fieldbus) – Profiles for functional
safety . 49
7 Communication Profile Family 2 (CIP™) and Family 16 (SERCOS®) – Profiles for

functional safety . 49
8 Communication Profile Family 3 (PROFIBUS™, PROFINET™) – Profiles for
functional safety . 49
9 Communication Profile Family 6 (INTERBUS®) – Profiles for functional safety . 50
10 Communication Profile Family 8 (CC-Link™) – Profiles for functional safety . 50
10.1 Functional Safety Communication Profile 8/1 . 50
10.2 Functional Safety Communication Profile 8/2 . 51
11 Communication Profile Family 12 (EtherCAT™) – Profiles for functional safety. 51
12 Communication Profile Family 13 (Ethernet POWERLINK™) – Profiles for
functional safety . 51
13 Communication Profile Family 14 (EPA®) – Profiles for functional safety . 51
14 Communication Profile Family 17 (RAPIEnet™) – Profiles for functional safety. 52
15 Communication Profile Family 18 (SafetyNET p™ Fieldbus) – Profiles for
functional safety .
Annex A (informative) Example functional safety communication models . 53
A.1 General . 53
A.2 Model A (single message, channel and FAL, redundant SCLs) . 53
A.3 Model B (full redundancy) . 53
A.4 Model C (redundant messages, FALs and SCLs, single channel) . 54
A.5 Model D (redundant messages and SCLs, single channel and FAL) . 54
Annex B (normative) Safety communication channel model using CRC-based error
checking . 56
B.1 Overview. 56
B.2 Channel model for calculations . 56
B.3 Bit error probability Pe . 57
B.4 Cyclic redundancy checking . 58
B.4.1 General . 58
B.4.2 Requirements for methods to calculate R . 58
CRC
REDLINE VERSION – 4 – IEC 61784-3:2021+AMD1:2024 CSV
© IEC 2024
Annex C (informative) Structure of technology-specific parts. 60
Annex D (informative) Assessment guideline . 63
D.1 Overview. 63
D.2 Channel types .
...

IEC 61784-3 ®
Edition 4.0 2021-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Industrial communication networks – Profiles –
Part 3: Functional safety fieldbuses – General rules and profile definitions

Réseaux de communication industriels – Profils –
Partie 3: Bus de terrain de sécurité fonctionnelle – Règles générales et
définitions de profils
All rights reserved. Unless otherwise specified, 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
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International Standards for all electrical, electronic and related technologies.

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latest edition, a corrigendum or an amendment might have been published.

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IEC 61784-3 ®
Edition 4.0 2021-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Industrial communication networks – Profiles –

Part 3: Functional safety fieldbuses – General rules and profile definitions

Réseaux de communication industriels – Profils –

Partie 3: Bus de terrain de sécurité fonctionnelle – Règles générales et

définitions de profils
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 25.040.40; 35.100.05 ISBN 978-2-8322-9268-6

– 2 – IEC 61784-3:2021 © IEC 2021
CONTENTS
FOREWORD . 7
0 Introduction . 9
0.1 General . 9
0.2 Use of extended assessment methods in Edition 4 . 11
0.3 Patent declaration . 11
1 Scope . 12
2 Normative references . 12
3 Terms, definitions, symbols, abbreviated terms and conventions . 14
3.1 Terms and definitions . 14
3.2 Symbols and abbreviated terms . 21
3.2.1 Abbreviated terms . 21
3.2.2 Symbols . 22
4 Conformance . 22
5 Basics of safety-related fieldbus systems . 23
5.1 Safety function decomposition . 23
5.2 Communication system . 23
5.2.1 General . 23
5.2.2 IEC 61158 fieldbuses . 24
5.2.3 Communication channel types . 24
5.2.4 Safety function response time . 25
5.3 Communication errors . 25
5.3.1 General . 25
5.3.2 Corruption . 25
5.3.3 Unintended repetition . 26
5.3.4 Incorrect sequence . 26
5.3.5 Loss . 26
5.3.6 Unacceptable delay . 26
5.3.7 Insertion . 26
5.3.8 Masquerade. 26
5.3.9 Addressing . 26
5.4 Deterministic remedial measures . 27
5.4.1 General . 27
5.4.2 Sequence number. 27
5.4.3 Time stamp . 27
5.4.4 Time expectation . 27
5.4.5 Connection authentication . 27
5.4.6 Feedback message . 27
5.4.7 Data integrity assurance . 27
5.4.8 Redundancy with cross checking . 28
5.4.9 Different data integrity assurance systems . 28
5.5 Typical relationships between errors and safety measures . 28
5.6 Communication phases . 29
5.7 FSCP implementation aspects . 30
5.8 Models for estimation of the total residual error rate . 30
5.8.1 Applicability . 30
5.8.2 General models for black channel communications . 31

5.8.3 Identification of generic safety properties . 31
5.8.4 Assumptions for residual error rate calculations . 32
5.8.5 Residual error rates . 33
5.8.6 Data integrity . 35
5.8.7 Authenticity. 36
5.8.8 Timeliness . 38
5.8.9 Masquerade. 41
5.8.10 Calculation of the total residual error rates . 41
5.8.11 Total residual error rate and SIL . 43
5.8.12 Configuration and parameterization for an FSCP . 43
5.9 Relationship between functional safety and security . 45
5.10 Boundary conditions and constraints . 45
5.10.1 Electrical safety . 45
5.10.2 Electromagnetic compatibility (EMC) . 46
5.11 Installation guidelines . 46
5.12 Safety manual . 46
5.13 Safety policy . 46
6 Communication Profile Family 1 (FOUNDATION™ Fieldbus) – Profiles for functional
safety . 47
7 Communication Profile Family 2 (CIP™) and Family 16 (SERCOS®) – Profiles for
functional safety . 47
8 Communication Profile Family 3 (PROFIBUS™, PROFINET™) – Profiles for
functional safety . 48
9 Communication Profile Family 6 (INTERBUS®) – Profiles for functional safety . 48
10 Communication Profile Family 8 (CC-Link™) – Profiles for functional safety . 49
10.1 Functional Safety Communication Profile 8/1 . 49
10.2 Functional Safety Communication Profile 8/2 . 49
11 Communication Profile Family 12 (EtherCAT™) – Profiles for functional safety. 49
12 Communication Profile
...