Industrial communication networks - Profiles - Part 3: Functional safety fieldbuses - General rules and profile definitions (IEC 61784-3:2021)

This part of the IEC 61784-3 series 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) 1
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.
This part and the IEC 61784-3-x parts specify several functional safety communication
profiles based on the communication profiles and protocol layers of the fieldbus technologies
in IEC 61784-1, IEC 61784-2 and IEC 61158 (all parts). These functional safety
communication profiles use the black channel approach, as defined in IEC 61508. These
functional safety communication profiles are intended for implementation in safety devices
exclusively.
NOTE 1 Other safety-related communication systems meeting the requirements of IEC 61508 (all parts) can exist
that are not included in IEC 61784-3 (all parts).
NOTE 2 It does not cover electrical safety and intrinsic safety aspects. Electrical safety relates to hazards such
as electrical shock. Intrinsic safety relates to hazards associated with potentially explosive atmospheres.
All systems are exposed to unauthorized access at some point of their life cycle. Additional
measures need to be considered in any safety-related application to protect fieldbus systems
against unauthorized access. IEC 62443 (all parts) will address many of these issues; the
relationship with IEC 62443 (all parts) is detailed in a dedicated subclause of this document.
NOTE 3 Implementation of a functional safety communication profile according to this document in a device is not
sufficient to qualify it as a safety device, as defined in IEC 61508 (all parts).
NOTE 4 The resulting SIL claim of a system depends on the implementation of the selected functional safety
communication profile within this system.
NOTE 5 Annex C explains the numbering scheme used for the technology-specific parts (IEC 61784-3-x) as well
as their common general structure.
NOTE 6 Annex D provides a guideline for the assessment and test of safety communication profiles as well as
safety-related devices using these profiles.

Industrielle Kommunikationsnetze - Profile - Teil 3: Funktional sichere Übertragung bei Feldbussen - Allgemeine Regeln und Festlegungen für Profile (IEC 61784-3:2021)

Réseaux de communication industriels - Profils - Partie 3: Bus de terrain de sécurité fonctionnelle - Règles générales et définitions de profils (IEC 61784-3:2021)

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.

Industrijska komunikacijska omrežja - Profili - 3. del: Funkciijska varnost procesnih vodil - Splošna pravila in definicije profilov (IEC 61784-3:2021)

General Information

Status
Published
Public Enquiry End Date
12-Apr-2020
Publication Date
25-May-2021
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
31-Mar-2021
Due Date
05-Jun-2021
Completion Date
26-May-2021

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SLOVENSKI STANDARD
SIST EN IEC 61784-3:2021
01-julij-2021
Nadomešča:
SIST EN 61784-3:2017
SIST EN 61784-3:2017/A1:2018
Industrijska komunikacijska omrežja - Profili - 3. del: Funkciijska varnost
procesnih vodil - Splošna pravila in definicije profilov (IEC 61784-3:2021)

Industrial communication networks - Profiles - Part 3: Functional safety fieldbuses -

General rules and profile definitions (IEC 61784-3:2021)

Industrielle Kommunikationsnetze - Profile - Teil 3: Funktional sichere Übertragung bei

Feldbussen - Allgemeine Regeln und Festlegungen für Profile (IEC 61784-3:2021)

Réseaux de communication industriels - Profils - Partie 3: Bus de terrain de sécurité

fonctionnelle - Règles générales et définitions de profils (IEC 61784-3:2021)
Ta slovenski standard je istoveten z: EN IEC 61784-3:2021
ICS:
25.040.40 Merjenje in krmiljenje Industrial process
industrijskih postopkov measurement and control
35.100.05 Večslojne uporabniške Multilayer applications
rešitve
SIST EN IEC 61784-3:2021 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
SIST EN IEC 61784-3:2021
---------------------- Page: 2 ----------------------
SIST EN IEC 61784-3:2021
EUROPEAN STANDARD EN IEC 61784-3
NORME EUROPÉENNE
EUROPÄISCHE NORM
March 2021
ICS 25.040.40; 35.100.05 Supersedes EN 61784-3:2016 and all of its amendments
and corrigenda (if any)
English Version
Industrial communication networks - Profiles - Part 3: Functional
safety fieldbuses - General rules and profile definitions
(IEC 61784-3:2021)

Réseaux de communication industriels - Profils - Partie 3: Industrielle Kommunikationsnetze - Profile - Teil 3:

Bus de terrain de sécurité fonctionnelle - Règles générales Funktional sichere Übertragung bei Feldbussen -

et définitions de profils Allgemeine Regeln und Festlegungen für Profile
(IEC 61784-3:2021) (IEC 61784-3:2021)

This European Standard was approved by CENELEC on 2021-03-23. CENELEC members are bound to comply with the CEN/CENELEC

Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.

Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC

Management Centre or to any CENELEC member.

This European Standard exists in three official versions (English, French, German). A version in any other language made by translation

under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the

same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,

Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the

Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,

Turkey and the United Kingdom.
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels

© 2021 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.

Ref. No. EN IEC 61784-3:2021 E
---------------------- Page: 3 ----------------------
SIST EN IEC 61784-3:2021
EN IEC 61784-3:2021 (E)
European foreword

The text of document 65C/1067/FDIS, future edition 4 of IEC 61784-3, prepared by SC 65C "Industrial

networks" of IEC/TC 65 "Industrial-process measurement, control and automation" was submitted to

the IEC-CENELEC parallel vote and approved by CENELEC as EN IEC 61784-3:2021.
The following dates are fixed:

• latest date by which the document has to be implemented at national (dop) 2021-12-23

level by publication of an identical national standard or by endorsement

• latest date by which the national standards conflicting with the (dow) 2024-03-23

document have to be withdrawn

This document supersedes EN 61784-3:2016 and all of its amendments and corrigenda (if any).

Attention is drawn to the possibility that some of the elements of this document may be the subject of

patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights.

Endorsement notice

The text of the International Standard IEC 61784-3:2021 was approved by CENELEC as a European

Standard without any modification.

In the official version, for Bibliography, the following notes have to be added for the standards

indicated:
IEC 61000-1-2 NOTE Harmonized as EN 61000-1-2
IEC 61131-6 NOTE Harmonized as EN 61131-6
IEC 61158-2:2014 NOTE Harmonized as EN 61158-2:2014 (not modified)
IEC 61158-3-1 NOTE Harmonized as EN 61158-3-1
IEC 61158-3-2 NOTE Harmonized as EN 61158-3-2
IEC 61158-3-3 NOTE Harmonized as EN 61158-3-3
IEC 61158-3-8 NOTE Harmonized as EN 61158-3-8
IEC 61158-3-12 NOTE Harmonized as EN IEC 61158-3-12
IEC 61158-3-13 NOTE Harmonized as EN 61158-3-13
IEC 61158-3-14 NOTE Harmonized as EN 61158-3-14
IEC 61158-3-18 NOTE Harmonized as EN 61158-3-18
IEC 61158-3-19 NOTE Harmonized as EN IEC 61158-3-19
IEC 61158-3-21 NOTE Harmonized as EN IEC 61158-3-21
IEC 61158-3-22 NOTE Harmonized as EN 61158-3-22
IEC 61158-4-1 NOTE Harmonized as EN 61158-4-1
IEC 61158-4-2 NOTE Harmonized as EN IEC 61158-4-2
IEC 61158-4-3 NOTE Harmonized as EN IEC 61158-4-3
IEC 61158-4-8 NOTE Harmonized as EN 61158-4-8
IEC 61158-4-12 NOTE Harmonized as EN IEC 61158-4-12
IEC 61158-4-13 NOTE Harmonized as EN 61158-4-13
IEC 61158-4-14 NOTE Harmonized as EN 61158-4-14
IEC 61158-4-18 NOTE Harmonized as EN 61158-4-18
IEC 61158-4-19 NOTE Harmonized as EN IEC 61158-4-19
---------------------- Page: 4 ----------------------
SIST EN IEC 61784-3:2021
EN IEC 61784-3:2021 (E)
IEC 61158-4-21 NOTE Harmonized as EN IEC 61158-4-21
IEC 61158-4-22 NOTE Harmonized as EN 61158-4-22
IEC 61158-5-2 NOTE Harmonized as EN IEC 61158-5-2
IEC 61158-5-3 NOTE Harmonized as EN 61158-5-3
IEC 61158-5-5 NOTE Harmonized as EN 61158-5-5
IEC 61158-5-8 NOTE Harmonized as EN 61158-5-8
IEC 61158-5-9 NOTE Harmonized as EN 61158-5-9
IEC 61158-5-10 NOTE Harmonized as EN IEC 61158-5-10
IEC 61158-5-12 NOTE Harmonized as EN IEC 61158-5-12
IEC 61158-5-13 NOTE Harmonized as EN 61158-5-13
IEC 61158-5-14 NOTE Harmonized as EN 61158-5-14
IEC 61158-5-18 NOTE Harmonized as EN 61158-5-18
IEC 61158-5-19 NOTE Harmonized as EN IEC 61158-5-19
IEC 61158-5-21 NOTE Harmonized as EN IEC 61158-5-21
IEC 61158-5-22 NOTE Harmonized as EN 61158-5-22
IEC 61158-5-23 NOTE Harmonized as EN IEC 61158-5-23
IEC 61158-6-2 NOTE Harmonized as EN IEC 61158-6-2
IEC 61158-6-3 NOTE Harmonized as EN IEC 61158-6-3
IEC 61158-6-5 NOTE Harmonized as EN 61158-6-5
IEC 61158-6-8 NOTE Harmonized as EN 61158-6-8
IEC 61158-6-9 NOTE Harmonized as EN 61158-6-9
IEC 61158-6-10 NOTE Harmonized as EN IEC 61158-6-10
IEC 61158-6-12 NOTE Harmonized as EN IEC 61158-6-12
IEC 61158-6-13 NOTE Harmonized as EN 61158-6-13
IEC 61158-6-14 NOTE Harmonized as EN 61158-6-14
IEC 61158-6-18 NOTE Harmonized as EN 61158-6-18
IEC 61158-6-19 NOTE Harmonized as EN IEC 61158-6-19
IEC 61158-6-21 NOTE Harmonized as EN IEC 61158-6-21
IEC 61158-6-22 NOTE Harmonized as EN 61158-6-22
IEC 61158-6-23 NOTE Harmonized as EN IEC 61158-6-23
IEC 61496 (series) NOTE Harmonized as EN IEC 61496 (series)
IEC 61496-1 NOTE Harmonized as EN IEC 61496-1
IEC 61508-4:2010 NOTE Harmonized as EN 61508-4:2010 (not modified)
IEC 61508-5:2010 NOTE Harmonized as EN 61508-5:2010 (not modified)
IEC 61511 (series) NOTE Harmonized as EN 61511 (series)
IEC 61800-5-2 NOTE Harmonized as EN 61800-5-2
IEC 62061:2005 NOTE Harmonized as EN 62061:2005 (not modified)
IEC 62061:2005/A1:2012 NOTE Harmonized as EN 62061:2005/A1:2013 (not modified)
IEC 62061:2005/A2:2015 NOTE Harmonized as EN 62061:2005/A2:2015 (not modified)
ISO 10218-1 NOTE Harmonized as EN ISO 10218-1
ISO 13849 (series) NOTE Harmonized as EN ISO 13849 (series)
ISO 13849-1:2015 NOTE Harmonized as EN ISO 13849-1:2015 (not modified)
---------------------- Page: 5 ----------------------
SIST EN IEC 61784-3:2021
EN IEC 61784-3:2021 (E)
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications

The following documents are referred to in the text in such a way that some or all of their content

constitutes requirements of this document. For dated references, only the edition cited applies. For

undated references, the latest edition of the referenced document (including any amendments)

applies.

NOTE 1 Where an International Publication has been modified by common modifications, indicated by (mod),

the relevant EN/HD applies.

NOTE 2 Up-to-date information on the latest versions of the European Standards listed in this annex is available

here: www.cenelec.eu.
Publication Year Title EN/HD Year
IEC 61000-6-7 - Electromagnetic compatibility (EMC) - Part EN 61000-6-7 -
6-7: Generic standards - Immunity
requirements for equipment intended to
perform functions in a safety-related system
(functional safety) in industrial locations

IEC 61010-2-201 - Safety requirements for electrical equipment EN IEC 61010-2-201 -

for measurement, control, and laboratory
use - Part 2-201: Particular requirements for
control equipment
IEC 61158 series Industrial communication networks - EN IEC 61158 series
Fieldbus specifications
IEC 61326-3-1 - Electrical equipment for measurement, EN 61326-3-1 -
control and laboratory use - EMC
requirements – Part 3-1: Immunity
requirements for safety-related systems and
for equipment intended to perform safety-
related functions (functional safety) –
General industrial applications
IEC 61326-3-2 - Electrical equipment for measurement, EN IEC 61326-3-2 -
control and laboratory use - EMC
requirements - Part 3-2: Immunity
requirements for safety-related systems and
for equipment intended to perform safety-
related functions (functional safety) -
Industrial applications with specified
electromagnetic environment
IEC 61508 series Functional safety of electrical EN 61508 series
/electronic/programmable electronic safety-
related systems
---------------------- Page: 6 ----------------------
SIST EN IEC 61784-3:2021
EN IEC 61784-3:2021 (E)
Publication Year Title EN/HD Year
IEC 61508-1 2010 Functional safety of electrical EN 61508-1 2010
/electronic/programmable electronic safety-
related systems - Part 1: General
requirements
IEC 61508-2 - Functional safety of electrical/ EN 61508-2 -
electronic/programmable electronic safety-
related systems - Part 2: Requirements for
electrical/electronic/programmable
electronic safety-related systems
IEC 61784-1 - Industrial communication networks - Profiles EN IEC 61784-1 -
Part 1: Fieldbus profiles
IEC 61784-2 - Industrial communication networks - Profiles EN IEC 61784-2 -
- Part 2: Additional fieldbus profiles for real-
time networks based on ISO/IEC/IEEE
8802-3
IEC 61784-3 series Industrial communication networks - Profiles - -
- Part 3: Functional safety fieldbuses
IEC 61784-3-1 - Industrial communication networks - Profiles EN 61784-3-1 -
- Part 3-1: Functional safety fieldbuses -
Additional specifications for CPF 1
IEC 61784-3-2 - Industrial communication networks - Profiles EN 61784-3-2 -
- Part 3-2: Functional safety fieldbuses -
Additional specifications for CPF 2
IEC 61784-3-3 - Industrial communication networks - Profiles EN 61784-3-3 -
- Part 3-3: Functional safety fieldbuses -
Additional specifications for CPF 3
IEC 61784-3-6 - Industrial communication networks - Profiles EN 61784-3-6 -
- Part 3-6: Functional safety fieldbuses -
Additional specifications for CPF 6
IEC 61784-3-8 - Industrial communication networks - Profiles EN 61784-3-8 -
- Part 3-8: Functional safety fieldbuses -
Additional specifications for CPF 8
IEC 61784-3-12 - Industrial communication networks - Profiles EN 61784-3-12 -
- Part 3-12: Functional safety fieldbuses -
Additional specifications for CPF 12
IEC 61784-3-13 - Industrial communication networks - Profiles EN 61784-3-13 -
- Part 3-13: Functional safety fieldbuses -
Additional specifications for CPF 13
IEC 61784-3-14 - Industrial communication networks - Profiles EN 61784-3-14 -
- Part 3-14: Functional safety fieldbuses -
Additional specifications for CPF 14
---------------------- Page: 7 ----------------------
SIST EN IEC 61784-3:2021
EN IEC 61784-3:2021 (E)
Publication Year Title EN/HD Year
IEC 61784-3-17 - Industrial communication networks - Profiles EN 61784-3-17 -
- Part 3-17: Functional safety fieldbuses -
Additional specifications for CPF 17
IEC 61784-3-18 - Industrial communication networks - Profiles EN 61784-3-18 -
- Part 3-18: Functional safety fieldbuses -
Additional specifications for CPF 18

IEC 61784-5 series Industrial communication networks - Profiles EN 61784-5 series

- Part 5: Installation of fieldbuses
IEC 61918 2018 Industrial communication networks - EN IEC 61918 2018
Installation of communication networks in
industrial premises
- - EN IEC 61918:2018 2019
/AC:2019-03
IEC 62443 series Security for industrial process measurement - -
and control - Network and system security
---------------------- Page: 8 ----------------------
SIST EN IEC 61784-3:2021
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

Warning! Make sure that you obtained this publication from an authorized distributor.

Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.

® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
---------------------- Page: 9 ----------------------
SIST EN IEC 61784-3:2021
– 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

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SIST EN IEC 61784-3:2021
IEC 61784-3:2021 © IEC 2021 – 3 –

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 Family 13 (Ethernet POWERLINK™) – Profiles for

functional safety ............................................................................................................ 50

13 Communication Profile Family 14 (EPA®) – Profiles for functional safety ....................... 50

14 Communication Profile Family 17 (RAPIEnet™) – Profiles for functional safety.............. 50

15 Communication Profile Family 18 (SafetyNET p™ Fieldbus) – Profiles for

functional safety ............................................................................................................ 51

Annex A (informative) Example functional safety communication models ............................. 52

A.1 General ................................................................................................................. 52

A.2 Model A (single message, channel and FAL, redundant SCLs) .............................. 52

A.3 Model B (full redundancy) ..................................................................................... 52

A.4 Model C (redundant messages, FALs and SCLs, single channel) .......................... 53

A.5 Model D (redundant messages and SCLs, single channel and FAL) ...................... 53

Annex B (normative) Safety communication channel model using CRC-based error

checking ............................................................................................................................... 55

B.1 Overview............................................................................................................... 55

B.2 Channel model for calculations ............................................................................. 55

B.3 Bit error probability Pe .......................................................................................... 56

B.4 Cyclic redundancy checking .................................................................................. 57

B.4.1 General ......................................................................................................... 57

B.4.2 Requirements for methods to calculate R ............................................... 57

CRC

Annex C (informative) Structure of technology-specific parts................................................ 59

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SIST EN IEC 61784-3:2021
– 4 – IEC 61784-3:2021 © IEC 2021

Annex D (informative) Assessment guideline ....................................................................... 62

D.1 Overview............................................................................................................... 62

D.2 Channel types ....................................................................................................... 62

D.2.1 General ......................................................................................................... 62

D.2.2 Black channel ................................................................................................ 62

D.2.3 White channel ................................................................................................ 62

D.3 Data integrity considerations for white channel approaches .................................. 63

D.3.1 General ......................................................................................................... 63

D.3.2 Models B and C ............................................................................................. 63

D.3.3 Models A and D ............................................................................................. 64

D.4 Verification of safety measures ............................................................................. 64

D.4.1 General ......................................................................................................... 64

D.4.2 Implementation .............................................................................................. 65

D.4.3 Default safety action ...................................................................................... 65

D.4.4 Safe state ...................................................................................................... 65

D.4.5 Transmission errors ....................................................................................... 65

D.4.6 Safety reaction and response times ............................................................... 65

D.4.7 Combination of measures .............................................................................. 65

D.4.8 Absence of interference ................................................................................. 66

D.4.9 Additional fault causes (white channel) .......................................................... 66

D.4.10 Reference test beds and operational conditions ............................................. 66

D.4.11 Conformance tester ....................................................................................... 66

Annex E (informative) Examples of implicit vs. explicit FSCP safety measures..................... 67

E.1 General ................................................................................................................. 67

E.2 Example fieldbus message with safety PDUs ........................................................ 67

E.3 Model with completely explicit safety measures .................................................... 67

E.4 Model with explicit A-code and implicit T-code safety measures ............................ 68

E.5 Model with explicit T-code and implicit A-code safety measures ............................ 68

E.6 Model with split explicit and implicit safety measures ............................................ 69

E.7 Model with completely implicit safety measures .................................................... 70

E.8 Addition to Annex B – impact of implicit codes on properness ............................... 70

Annex F (informative) Legacy models for estimation of the total residual error rate .............. 71

F.1 General ................................................................................................................. 71

F.2 Calculation of the residual error rate ..................................................................... 71

F.3 Total residual error rate and SIL ........................................................................... 73

Annex G (informative) Implicit data safety mechanisms for
...

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