EN 61784-3-8:2017

SLOVENSKI STANDARD
01-februar-2018
1DGRPHãþD
SIST EN 61784-3-8:2010
Industrijska komunikacijska omrežja - Profili - 3-8. del: Funkcijska varnost
procesnih vodil - Dodatne specifikacije za CPF 8 (IEC 61784-3-8:2016)
Industrial communication networks - Profiles - Part 3-8: Functional safety fieldbuses -
Additional specifications for CPF 8 (IEC 61784-3-8:2016)
Industrielle Kommunikationsnetze - Profile - Teil 3-8: Funktional sichere Übertragung bei
Feldbussen - Zusätzliche Festlegungen für die Kommunikationsprofilfamilie 8 (IEC
61784-3-8:2016)
Réseaux de communication industriels - Profils - Partie 3-8: Bus de terrain de sécurité
fonctionnelle - Spécification supplémentaire pour CPF 8 (IEC 61784-3-8:2016)
Ta slovenski standard je istoveten z: EN 61784-3-8:2017
ICS:
25.040.40 Merjenje in krmiljenje Industrial process
industrijskih postopkov measurement and control
35.100.05 9HþVORMQHXSRUDEQLãNH Multilayer applications
UHãLWYH
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN 61784-3-8

NORME EUROPÉENNE
EUROPÄISCHE NORM
December 2017
ICS 25.040.40; 35.100.05 Supersedes EN 61784-3-8:2010
English Version
Industrial communication networks - Profiles - Part 3-8:
Functional safety fieldbuses - Additional specifications for CPF 8
(IEC 61784-3-8:2016)
Réseaux de communication industriels - Profils - Partie 3-8: Industrielle Kommunikationsnetze - Profile - Teil 3-8:
Bus de terrain de sécurité fonctionnelle - Spécification Funktional sichere Übertragung bei Feldbussen -
supplémentaire pour CPF 8 Zusätzliche Festlegungen für die
(IEC 61784-3-8:2016) Kommunikationsprofilfamilie 8
(IEC 61784-3-8:2016)
This European Standard was approved by CENELEC on 2016-09-01. 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, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, 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: Avenue Marnix 17, B-1000 Brussels
© 2017 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN 61784-3-8:2017 E
European foreword
The text of document 65C/851/FDIS, future edition 2 of IEC 61784-3-8:2016, 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 61784-3-8:2017.

The following dates are fixed:

• latest date by which this document has (dop) 2018-06-01
to be implemented at national level by
publication of an identical national
standard or by endorsement
• latest date by which the national (dow) 2020-12-01
standards conflicting with this
document have to be withdrawn
This document supersedes EN 61784-3-8:2010.

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 61784-3-8:2016 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 61000-6-7 NOTE  Harmonized as EN 61000-6-7
IEC 61131-6 NOTE  Harmonized as EN 61131-6
IEC 61496 (all parts) NOTE  Harmonized as EN 61496 (all parts)
IEC 61508-1:2010 NOTE  Harmonized as EN 61508-1:2010 (not modified).
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 61784-2 NOTE  Harmonized as EN 61784-2
IEC 61784-5 (all parts) NOTE  Harmonized as EN 61784-5 (all parts)
IEC 61800-5-2 NOTE  Harmonized as EN 61800-5-2
IEC 61918 NOTE  Harmonized as EN 61918
IEC 62443 (all parts) NOTE  Harmonized as prEN 62443 (all parts)
IEC/TR 62685 NOTE  Harmonized as CLC/TR 62685
ISO 10218-1 NOTE  Harmonized as EN ISO 10218-1
ISO 12100 NOTE  Harmonized as EN ISO 12100
ISO 13849-1 NOTE  Harmonized as EN ISO 13849-1
ISO 13849-2 NOTE  Harmonized as EN ISO 13849-2
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 When 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 60204-1 -  Safety of machinery - Electrical equipment - -
of machines - Part 1: General
requirements
IEC 61131-2 2007 Programmable controllers -- Part 2: EN 61131-2 2007
Equipment requirements and tests
IEC 61158 series Industrial communication networks - EN 61158 series
Fieldbus specifications - Part 1: Overview
and guidance for the IEC 61158 and IEC
61784 series
IEC 61158-2 -  Industrial communication networks - EN 61158-2 -
Fieldbus specifications - Part 2: Physical
layer specification and service definition
IEC 61158-3-18 -  Industrial communication networks - EN 61158-3-18 -
Fieldbus specifications - Part 3-18: Data-
link layer service definition - Type 18
elements
IEC 61158-4-18 -  Industrial communication networks - EN 61158-4-18 -
Fieldbus specifications -- Part 4-18: Data-
link layer protocol specification - Type 18
elements
IEC 61158-5-18 -  Industrial communication networks - EN 61158-5-18 -
Fieldbus specifications -- Part 5-18:
Application layer service definition - Type
18 elements
IEC 61158-5-23 -  Industrial communication networks - EN 61158-5-23 -
Fieldbus specifications - Part 5-23:
Application layer service definition - Type
23 elements
IEC 61158-6-18 -  Industrial communication networks - EN 61158-6-18 -
Fieldbus specifications - Part 6-18:
Application layer protocol specification -
Type 18 elements
IEC 61158-6-23 -  Industrial communication networks - EN 61158-6-23 -
Fieldbus specifications - Part 6-23:
Application layer protocol specification -
Type 23 elements
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, - -
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 EN 61508 series
electrical/electronic/programmable
electronic safety-related systems -- Part 1:
General requirements
IEC 61511 series Functional safety - Safety instrumented EN 61511 series
systems for the process industry sector -
Part 1: Framework, definitions, system,
hardware and application programming
requirements
IEC 61784-1 -  Industrial communication networks - EN 61784-1 -
Profiles - Part 1: Fieldbus profiles
IEC 61784-2 -  Industrial communication networks - EN 61784-2 -
Profiles - Part 2: Additional fieldbus profiles
for real-time networks based on ISO/IEC
8802-3
IEC 61784-3 -  Industrial communication networks - EN 61784-3 -
Profiles - Part 3: Functional safety
fieldbuses - General rules and profile
definitions
IEC 62061 -  Safety of machinery - Functional safety of EN 62061 -
safety-related electrical, electronic and
programmable electronic control systems
IEEE 802.3 -  IEEE Standard for Information technology - - -
Specific requirements - Part 3: Carrier
Sense Multiple Access with Collision
Detection (CMSA/CD) Access Method and
Physical Layer Specifications
IEC 61784-3-8 ®
Edition 2.0 2016-07
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Industrial communication networks – Profiles –

Part 3-8: Functional safety fieldbuses – Additional specifications for CPF 8

Réseaux de communication industriels – Profils –

Partie 3-8: Bus de terrain de sécurité fonctionnelle – Spécifications

supplémentaires pour CPF 8
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 25.040.40, 35.100.05 ISBN 978-2-8322-3491-4

– 2 – IEC 61784-3-8:2016  IEC 2016
CONTENTS
FOREWORD . 7
0 Introduction . 9
0.1 General . 9
0.2 Patent declaration . 11
1 Scope . 12
2 Normative references. 12
3 Terms, definitions, symbols, abbreviated terms and conventions. 13
3.1 Terms and definitions . 13
3.1.1 Common terms and definitions . 14
3.1.2 CPF 8: Additional terms and definitions . 20
3.2 Symbols and abbreviated terms . 21
3.2.1 Common symbols and abbreviated terms . 21
3.2.2 CPF 8: Additional symbols and abbreviated terms . 22
3.3 Conventions . 22
4 Overview . 22
5 General . 22
6 Safety communication layer services . 23
7 Safety communication layer protocol . 23
8 Safety communication layer management . 23
9 System requirements . 23
10 Assessment . 23
11 FSCP 8/1 . 23
11.1 Scope – FSCP 8/1 . 23
11.2 Normative references – FSCP 8/1 . 23
11.3 Terms, definitions, symbols, abbreviated terms and conventions – FSCP 8/1 . 23
11.4 Overview of FSCP 8/1 (CC-Link Safety™) . 23
11.5 General – FSCP 8/1 . 24
11.5.1 External documents providing specifications for the profile . 24
11.5.2 Safety functional requirements . 24
11.5.3 Safety measures . 24
11.5.4 Safety communication layer structure . 26
11.5.5 Relationships with FAL (and DLL, PhL) . 26
11.6 Safety communication layer services for FSCP 8/1. 27
11.6.1 General . 27
11.6.2 SASEs . 27
11.6.3 SARs . 28
11.6.4 Process data SAR ASEs . 28
11.7 Safety communication layer protocol for FSCP 8/1 . 29
11.7.1 Safety PDU format . 29
11.7.2 State description . 36
11.8 Safety communication layer management for FSCP 8/1 . 40
11.8.1 General . 40
11.8.2 Connection establishment and confirmation processing . 41
11.8.3 Safety slave verification . 41
11.9 System requirements for FSCP 8/1 . 42

IEC 61784-3-8:2016  IEC 2016 – 3 –
11.9.1 Indicators and switches . 42
11.9.2 Installation guidelines . 43
11.9.3 Safety function response time . 43
11.9.4 Duration of demands . 45
11.9.5 Constraints for calculation of system characteristics . 45
11.9.6 Maintenance . 46
11.9.7 Safety manual . 47
11.10 Assessment for FSCP 8/1 . 47
12 FSCP 8/2 . 47
12.1 Scope – FSCP 8/2 . 47
12.2 Normative references – FSCP 8/2 . 47
12.3 Terms, definitions, symbols, abbreviated terms and conventions – FSCP 8/2 . 47
12.4 Overview of FSCP 8/2 (CC-Link IE™ Safety communication function) . 47
12.5 General – FSCP 8/2 . 48
12.5.1 External documents providing specifications for the profile . 48
12.5.2 Safety functional requirements . 48
12.5.3 Safety measures . 49
12.5.4 Safety communication layer structure . 53
12.5.5 Relationships with FAL (and DLL, PhL) . 54
12.6 Safety communication layer services for FSCP 8/2. 54
12.6.1 General . 54
12.6.2 Connection reestablishment services . 54
12.6.3 Data transmission services . 55
12.6.4 Connection termination notification services . 56
12.7 Safety communication layer protocol for FSCP 8/2 . 56
12.7.1 Safety PDU format . 56
12.7.2 Safety FAL service protocol machine (SFSPM) . 62
12.8 Safety communication layer management for FSCP 8/2 . 85
12.8.1 Parameter Definitions . 85
12.8.2 Parameter Setup . 89
12.8.3 Management Services . 89
12.9 System requirements for FSCP 8/2 . 92
12.9.1 Indicators and switches . 92
12.9.2 Installation guidelines . 94
12.9.3 Safety function response time . 94
12.9.4 Duration of demands . 95
12.9.5 Constraints for calculation of system characteristics . 95
12.9.6 Maintenance . 97
12.9.7 Safety manual . 97
12.10 Assessment for FSCP 8/2 . 98
Annex A (informative) Additional information for functional safety communication
profiles of CPF 8 . 99
A.1 Hash function calculation for FSCP 8/1 . 99
A.2 Hash function calculation for FSCP 8/2 . 99
A.3 Meaning of response time calculation formula for FSCP 8/2 . 99
Annex B (informative) Information for assessment of the functional safety
communication profiles of CPF 8 . 100
Bibliography . 101

– 4 – IEC 61784-3-8:2016  IEC 2016
Figure 1 – Relationships of IEC 61784-3 with other standards (machinery) . 9
Figure 2 – Relationships of IEC 61784-3 with other standards (process) . 10
Figure 3 – Relationship between SCL and the other layers of IEC 61158 Type 18 . 26
Figure 4 – State diagram . 37
Figure 5 – Detection of unintended repetition . 50
Figure 6 – Detection of incorrect sequence . 51
Figure 7 – Detection of loss . 51
Figure 8 – Detection of unacceptable delay by time stamps . 52
Figure 9 – Detection of unacceptable delay by timer . 53
Figure 10 – Protocol Hierarchy . 54
Figure 11 – Safety PDU Structure . 57
Figure 12 – CTRL Configuration . 57
Figure 13 – SASE-M and SASE-S TS . 60
Figure 14 – S-Data during safety refresh . 60
Figure 15 – S-Data not during safety refresh . 61
Figure 16 – S-Data header configuration . 61
Figure 17 – CRC calculation . 62
Figure 18 – Communication models . 62
Figure 19 – SFSPM state transition diagram . 63
Figure 20 – Connection establishment sequence . 65
Figure 21 – Communication sequence during safety refresh communication . 65
Figure 22 – Offset measurement and generation sequence during safety refresh
communication . 66
Figure 23 – SFSPM-M state transition diagram . 67
Figure 24 – Sequence other than during safety refresh . 70
Figure 25 – S-Connect-req . 71
Figure 26 – S-InitConfirmNetPrm-req . 71
Figure 27 – net_prm_list . 72
Figure 28 – S-InitVerifyStnPrm-req . 72
Figure 29 – stn_prm_list . 72
Figure 30 – S-InvokeFunc-req . 73
Figure 31 – S-WriteErrorInfo-req . 73
Figure 32 – date_and_time_of_occurence . 74
Figure 33 – SFSPM-S state transition diagram . 75
Figure 34 – Sequence other than during safety refresh . 80
Figure 35 – S-Connect-rsp . 80
Figure 36 – S-InitConfirmNetPrm-rsp . 81
Figure 37 – S-InitVerifyStnPrm-rsp . 81
Figure 38 – S-InvokeFunc-rsp . 82
Figure 39 – Offset calculation procedure of safety clock . 83
Figure 40 – Relationship between transmission interval fluctuation and
transmission_interval . 86
Figure 41 – Calculation of allowable_refresh_interval . 88
Figure 42 – Calculation of allowable_delay . 89

IEC 61784-3-8:2016  IEC 2016 – 5 –
Figure 43 – Calculation of response time between safety PLCs . 94
Figure 44 – Relationship between safety connections and residual error rate . 97
Figure A.1 – allowable_delay and offset calculation deviation . 99

Table 1 – Selection of the various measures for possible errors . 25
Table 2 – M1 safety device manager attribute format . 30
Table 3 – S1 safety device manager attribute format . 30
Table 4 – M1 safety connection manager attribute format . 30
Table 5 – S1 safety connection manager attribute format . 30
Table 6 – M1 safety cyclic transmission attribute format . 31
Table 7 – S1 safety cyclic transmission attribute format . 31
Table 8 – M1 safety device manager attribute encoding . 32
Table 9 – S1 safety device manager attribute encoding . 32
Table 10 – M1 safety connection manager attribute encoding . 32
Table 11 – S1 safety connection manager attribute encoding . 33
Table 12 – M1 safety cyclic transmission attribute encoding. 33
Table 13 – S1 safety cyclic transmission attribute encoding . 35
Table 14 – Safety master monitor timer operation . 39
Table 15 – Safety slave monitor timer operation . 39
Table 16 – Safety data monitor timer operation . 39
Table 17 – Details of connection establishment and confirmation processing. 41
Table 18 – Details of slave information verification processing . 41
Table 19 – Details of safety slave parameter transmission processing . 42
Table 20 – Monitor LEDs . 43
Table 21 – Safety function response time calculation . 44
Table 22 – Safety function response time definition of terms . 44
Table 23 – Number of occupied slots and safety data . 45
Table 24 – Residual error rate Λ (occupied slots = 1) . 46
Table 25 – Residual error rate Λ (occupied slots = 2) . 46
Table 26 – Selection of the various measures for possible errors . 49
Table 27 – SS-Start . 54
Table 28 – SS-Restart . 55
Table 29 – SS-InvokeFunc . 55
Table 30 – SS-Read . 55
Table 31 – SS-Write . 56
Table 32 – SS-Terminate . 56
Table 33 – Safety PDU elements . 57
Table 34 – CTRL Elements . 58
Table 35 – State list . 63
Table 36 – SFSPM-M timers . 67
Table 37 – SFSPM-M state transition table . 67
Table 38 – support_functions . 71
Table 39 – error_category . 74

– 6 – IEC 61784-3-8:2016  IEC 2016
Table 40 – error_category for AL errors . 74
Table 41 – error_code . 74
Table 42 – SFSPM-S timers . 76
Table 43 – SFSPM-S state transition table . 76
Table 44 – Parameters used by safety communication layer . 85
Table 45 – SM-SetSafetyStationInfo . 89
Table 46 – Safety station information setting parameters of SM-SetSafetyStationInfo . 90
Table 47 – SM-SetSafetyNetworkParameter . 90
Table 48 – Safety network parameters of SM-SetSafetyNetworkParameter . 90
Table 49 – SM-GetSafetyStationInfo . 91
Table 50 – Safety station information parameters of SM-GetSafetyStationInfo (Request) . 91
Table 51 – Safety station information parameters of SM-GetSafetyStationInfo
(Response) . 91
Table 52 – SM-GetSafetyNetworkParameter . 92
Table 53 – Parameters of SM-GetSafetyNetworkParameter request . 92
Table 54 – Parameters of SM-GetSafetyNetworkParameter response . 92
Table 55 – Monitor LEDs . 93
Table 56 – Communication port monitor LEDs . 93

IEC 61784-3-8:2016  IEC 2016 – 7 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
INDUSTRIAL COMMUNICATION NETWORKS –
PROFILES –
Part 3-8: Functional safety fieldbuses –
Additional specifications for CPF 8

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; 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 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 possible, 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. 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 undertake 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 itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
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 including 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 reliance 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.
International Standard IEC 61784-3-8 has been prepared by subcommittee 65C: Industrial
networks, of IEC technical committee 65: Industrial-process measurement, control and
automation.
This second edition cancels and replaces the first edition published in 2010. This edition
constitutes a technical revision. This edition includes the following significant technical
changes with respect to the previous edition:
• Added FSCP 8/2;
• Added FSCP 8/2 Clause 12;
• Added content for FSCP 8/2 to Clauses 1 to 3 (scope, references, terms);
• Moved previous FSCP 8/1 to Clause 11 (demoting all old heading levels by one);
• Restructured old Clauses 4 to 10 to point to appropriate subclauses as appropriate.

– 8 – IEC 61784-3-8:2016  IEC 2016
The text of this standard is based on the following documents:
FDIS Report on voting
65C/851/FDIS 65C/854/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, Part 2.
A list of all parts of the IEC 61784-3 series, published under the general title Industrial
communication networks – Profiles – Functional safety fieldbuses, can be found on the IEC
website.
The committee has decided that the contents of this publication will remain unchanged until
the stability 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,
• replaced by a revised edition, or
• amended.
IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct
understanding of its contents. Users should therefore print this document using a
colour printer.
IEC 61784-3-8:2016  IEC 2016 – 9 –
0 Introduction
0.1 General
The IEC 61158 fieldbus standard together with its companion standards IEC 61784-1 and
IEC 61784-2 defines a set of communication protocols that enable distributed control of
automation applications. Fieldbus technology is now considered well accepted and well
proven. Thus fieldbus enhancements continue to emerge, addressing applications for areas
such as real time, safety-related and security-related applications.
This standard explains the relevant principles for functional safety communications with
reference to IEC 61508 series and specifies several safety communication layers (profiles and
corresponding protocols) based on the communication profiles and protocol layers of
IEC 61784-1, IEC 61784-2 and the IEC 61158 series. It does not cover electrical safety and
intrinsic safety aspects.
Figure 1 shows the relationships between this standard and relevant safety and fieldbus
standards in a machinery environment.
IEC
NOTE Subclauses 6.7.6.4 (high complexity) and 6.7.8.1.6 (low complexity) of IEC 62061 specify the relationship
between PL (Category) and SIL.
Figure 1 – Relationships of IEC 61784-3 with other standards (machinery)
Figure 2 shows the relationships between this standard and relevant safety and fieldbus
standards in a process environment.

– 10 – IEC 61784-3-8:2016  IEC 2016

IEC
a
For specified electromagnetic environments; otherwise IEC 61326-3-1 or IEC 61000-6-7.
b
EN ratified.
Figure 2 – Relationships of IEC 61784-3 with other standards (process)
Safety communication layers which are implemented as parts of safety-related systems
according to IEC 61508 series provide the necessary confidence in the transportation of
messages (information) between two or more participants on a fieldbus in a safety-related
system, or sufficient confidence of safe behaviour in the event of fieldbus errors or failures.
Safety communication layers specified in this standard do this in such a way that a fieldbus
can be used for applications requiring functional safety up to the Safety Integrity Level (SIL)
specified by its corresponding functional safety communication profile.
The resulting SIL claim of a system depends on the implementation of the selected functional
safety communication profile (FSCP) within this system – implementation of a functional
safety communication profile in a standard device is not sufficient to qualify it as a safety
device.
This standard describes:
– basic principles for implementing the requirements of IEC 61508 series for safety-
related data communications, including possible transmission faults, remedial
measures and considerations affecting data integrity;

IEC 61784-3-8:2016  IEC 2016 – 11 –
– functional safety communication profiles for several communication profile families in
IEC 61784-1 and IEC 61784-2, including safety layer extensions to the communication
service and protocols sections of the IEC 61158 series.
0.2 Patent declaration
The International Electrotechnical Commission (IEC) draws attention to the fact that it is
claimed that compliance with this document may involve the use of a patent concerning
FSCP 8/2 given in Clause 12 as follows:
JP 2012-533784
US 13/821733
Communication apparatus and delay detecting
DE 112010005881.4 [MEC]
method
KR 10-2013-7006469
CN 201080069108.6
IEC takes no position concerning the evidence, validity and scope of this patent right.
The holder of this patent right has assured the IEC that he/she is willing to negotiate licences
either free of charge or under reasonable and non-discriminatory terms and conditions with
applicants throughout the world. In this respect, the statement of the holder of this patent right
is registered with IEC. Information may be obtained from:
Mitsubishi Electric Corporation
Corporate Licensing Division
[MEC]
2-7-3 Marunouchi, Chiyoda-ku
Tokyo 100-8310 Japan
Attention is drawn to the possibility that some of the elements of this document may be the
subject of patent rights other than those identified above. IEC shall not be held responsible for
identifying any or all such patent rights.
ISO (www.iso.org/patents) and IEC (http://patents.iec.ch) maintain on-line data bases of
patents relevant to their standards. Users are encouraged to consult the data bases for the
most up-to-date information concerning patents.

– 12 – IEC 61784-3-8:2016  IEC 2016
INDUSTRIAL COMMUNICATION NETWORKS –
PROFILES –
Part 3-8: Functional safety fieldbuses –
Additional specifications for CPF 8

1 Scope
This part of the IEC 61784-3 series specifies a safety communication layer (services and
protocol) based on CPF 8 of IEC
...