SIST EN 61784-3-6:2010

SLOVENSKI STANDARD
01-oktober-2010
1DGRPHãþD
SIST EN 61784-3-6:2008
Industrijska komunikacijska omrežja - Profili - 3-6. del: Funkcijska varnost
procesnih vodil - Dodatne specifikacije za CPF 6 (IEC 61784-3-6:2010 )
Industrial communication networks - Profiles - Part 3-6: Functional safety fieldbuses -
Additional specifications for CPF 6 (IEC 61784-3-6:2010 )
Industrielle Kommunikationsnetze - Profile - Teil 3-6: Funktional sichere Übertragung bei
Feldbussen - Zusätzliche Festlegungen für die Kommunikationsprofilfamilie 6 (IEC 61784
-3-6:2010 )
Réseaux de communication industriels - Partie 3-6: Bus de terrain à sécurité
fonctionnelle - Spécifications complémentaires pour le CPF 6 (CEI 61784-3-6:2010 )
Ta slovenski standard je istoveten z: EN 61784-3-6:2010
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 61784-3-6
NORME EUROPÉENNE
August 2010
EUROPÄISCHE NORM
ICS 25.040.40; 35.100.05 Supersedes EN 61784-3-6:2008

English version
Industrial communication networks -
Profiles -
Part 3-6: Functional safety fieldbuses -
Additional specifications for CPF 6
(IEC 61784-3-6:2010)
Réseaux de communication industriels -  Industrielle Kommunikationsnetze -
Partie 3-6: Bus de terrain à sécurité Profile -
fonctionnelle - Teil 3-6: Funktional sichere Übertragung
Spécifications complémentaires bei Feldbussen -
pour le CPF 6 Zusätzliche Festlegungen
(CEI 61784-3-6:2010) für die Kommunikationsprofilfamilie 6
(IEC 61784-3-6:2010)
This European Standard was approved by CENELEC on 2010-07-01. 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 Central Secretariat 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 Central Secretariat 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, Romania, Slovakia, Slovenia,
Spain, Sweden, Switzerland and the United Kingdom.

CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung

Management Centre: Avenue Marnix 17, B - 1000 Brussels

© 2010 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 61784-3-6:2010 E
Foreword
The text of document 65C/591A/FDIS, future edition 2 of IEC 61784-3-6, 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 was approved by CENELEC as EN 61784-3-6 on 2010-07-01.
This European Standard supersedes EN 61784-3-6:2008.
The main changes with respect to EN 61784-3-6:2008 are listed below:
– updates in relation with changes in EN 61784-3.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN and CENELEC shall not be held responsible for identifying any or all such patent
rights.
The following dates were fixed:
– latest date by which the EN has to be implemented
at national level by publication of an identical
national standard or by endorsement (dop) 2011-04-01
– latest date by which the national standards conflicting
with the EN have to be withdrawn (dow) 2013-07-01
Annex ZA has been added by CENELEC.
__________
- 3 - EN 61784-3-6:2010
Endorsement notice
The text of the International Standard IEC 61784-3-6:2010 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:
EN 50170
IEC 61131-2 NOTE  Harmonized as EN 61131-2.
IEC 61326-3-1 NOTE  Harmonized as EN 61326-3-1.
IEC 61326-3-2 NOTE  Harmonized as EN 61326-3-2
IEC 61496 series NOTE  Harmonized in EN 61496 series (partially modified).
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 61508-6:2010 NOTE  Harmonized as EN 61508-6:2010 (not modified).
IEC 61784-5 series NOTE  Harmonized in EN 61784-5 series (not modified).
IEC 61800-5-2 NOTE  Harmonized as EN 61800-5-2.
ISO 10218-1 NOTE  Harmonized as EN ISO 10218-1.
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 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 the referenced
document (including any amendments) applies.

NOTE  When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD
applies.
Publication Year Title EN/HD Year

IEC 60204-1 - Safety of machinery - Electrical equipment of EN 60204-1 -
machines -
Part 1: General requirements
IEC 61131-3 - Programmable controllers - EN 61131-3 -
Part 3: Programming languages
IEC 61158 Series Industrial communication networks - EN 61158 Series
Fieldbus specifications
IEC 61158-2 - Industrial communication networks - EN 61158-2 -
Fieldbus specifications -
Part 2: Physical layer specification and service
definition
IEC 61158-3-8 - Industrial communication networks - EN 61158-3-8 -
Fieldbus specifications -
Part 3-8: Data-link layer service definition -
Type 8 elements
IEC 61158-4-8 - Industrial communication networks - EN 61158-4-8 -
Fieldbus specifications -
Part 4-8: Data-link layer protocol specification
- Type 8 elements
IEC 61158-5-8 2007 Industrial communication networks - EN 61158-5-8 2008
Fieldbus specifications -
Part 5-8: Application layer service definition -
Type 8 elements
IEC 61158-6-8 - Industrial communication networks - EN 61158-6-8 -
Fieldbus specifications -
Part 6-8: Application layer protocol
specification - Type 8 elements

IEC 61508 Series Functional safety of EN 61508 Series
electrical/electronic/programmable electronic
safety-related systems
IEC 61511 Series Functional safety - Safety instrumented EN 61511 Series
systems for the process industry sector

IEC 61784-1 - Industrial communication networks - Profiles - EN 61784-1 -
Part 1: Fieldbus profiles
IEC 61784-2 - Industrial communication networks - Profiles - EN 61784-2 -
Part 2: Additional fieldbus profiles for real-time
networks based on ISO/IEC 8802-3

- 5 - EN 61784-3-6:2010
Publication Year Title EN/HD Year

IEC 61784-3 2010 Industrial communication networks - Profiles - EN 61784-3 2010
Part 3: Functional safety fieldbuses - General
rules and profile definitions
IEC 61784-5-6 - Industrial communication networks - Profiles - EN 61784-5-6 -
Part 5-6: Installation of fieldbuses - Installation
profiles for CPF 6
IEC 61918 - Industrial communication networks - EN 61918 -
Installation of communication networks in
industrial premises
IEC 62061 - Safety of machinery - Functional safety of EN 62061 -
safety-related electrical, electronic and
programmable electronic control systems

ISO 12100-1 - Safety of machinery - Basic concepts, EN ISO 12100-1 -
general principles for design -
Part 1: Basic terminology, methodology

ISO 13849-1 - Safety of machinery - Safety-related parts EN ISO 13849-1 -
of control systems -
Part 1: General principles for design

IEC 61784-3-6 ®
Edition 2.0 2010-06
INTERNATIONAL
STANDARD
colour
inside
Industrial communication networks – Profiles –
Part 3-6: Functional safety fieldbuses – Additional specifications for CPF 6

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
XC
ICS 25.040.40; 35.100.05 ISBN 978-2-88910-979-1
– 2 – 61784-3-6 © IEC:2010(E)
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 .13
3.1.2 CPF 6: Additional terms and definitions .18
3.2 Symbols and abbreviated terms.18
3.2.1 Common symbols and abbreviated terms .18
3.2.2 CPF 6: Additional symbols and abbreviated terms .19
3.3 Conventions .20
4 Overview of FSCP 6/7 (INTERBUS™ Safety) .20
4.1 General .20
4.2 Technical overview.20
4.3 Functional Safety Communication Profile 6/7.21
5 General .22
5.1 External documents providing specifications for the profile.22
5.2 Safety functional requirements .22
5.3 Safety measures .22
5.3.1 General .22
5.3.2 Sequence number .23
5.3.3 Time stamp .23
5.3.4 Time expectation .23
5.3.5 Acknowledgement .23
5.3.6 Connection authentication .23
5.3.7 Distinction between safety relevant messages and non-safety
relevant messages – different data integrity assurance system.24
5.3.8 Parameterized shutdown time.24
5.4 Safety communication layer structure .24
5.4.1 Decomposition process.24
5.4.2 Definition of the safety function of the safety communication system .25
5.4.3 Decomposition of the safety function of a safety communication
system into function blocks.26
5.4.4 Assignment of the function blocks to subsystems .27
5.4.5 Safety requirements and safety integrity requirements.30
5.4.6 Specification of the safe state.30
5.4.7 Response to a fault .31
5.4.8 Stop category .33
5.4.9 Safe Transmission.33
5.5 Relationships with FAL (and DLL, PhL) .33
5.5.1 Overview .33
5.5.2 Use of the AR-US service to initiate and parameterize.34
5.5.3 Use of the AR-US service to transmit safety data .35

61784-3-6 © IEC:2010(E) – 3 –
5.5.4 Use of the AR-US service to abort .36
5.5.5 Data types .36
6 Safety communication layer services .36
6.1 General .36
6.2 Transmission principle for safety messages between SCLM and SCLS .36
6.3 Function block requirements.37
6.3.1 Input Safe Data function block .37
6.3.2 Output Safe Data function block .37
6.3.3 Safe Calculation function block.37
6.4 Context management .38
6.4.1 Initiate service .38
6.4.2 Abort service .39
6.5 Function block parameterization .40
6.5.1 Send application parameter service .40
6.5.2 Send application parameter ID service .41
6.5.3 Parameterize device service.42
6.6 Safe Process Data Mode.42
6.6.1 Transmit-Safety-Data .42
6.6.2 Set-Diagnostic-Data service .44
6.6.3 Set-Acknowledgement-Data service .44
7 Safety communication layer protocol .45
7.1 Safety PDU format .45
7.1.1 Structure of safety messages .45
7.1.2 Description of the polynomial used .46
7.1.3 Structure of safety messages for safe parameterization and idle .46
7.1.4 Structure of safety messages for the transmission of safety data.52
7.1.5 Messages for synchronization.53
7.1.6 Structure of safety messages for aborting connections .54
7.2 State description .54
7.2.1 SCLM and SCLS state machines .54
7.2.2 Initiate .56
7.2.3 Parameterization .57
7.2.4 Process data mode.61
7.2.5 Process data mode with diagnostic data transmission .66
7.2.6 Process data mode with Acknowledgement-Data transmission .66
7.2.7 Connection aborted .67
7.3 Abort .67
7.3.1 Connection abort in the event of an error detected by the SCLM .67
7.3.2 Abort of all connections in the event of an error detected by the
SCLS.68
7.3.3 Abort of all connections in the event of an error detected by the
SCLM .70
8 Safety communication layer management.71
8.1 General .71
8.2 Requirements of safety communication layer management.71
8.3 Set-Safety-Configuration service .71
8.4 Start IEC 61158 Type 8 service .73
9 System requirements.73
9.1 Indicators and switches .73

– 4 – 61784-3-6 © IEC:2010(E)
9.2 Installation guidelines.73
9.3 Safety function response time .73
9.3.1 General .73
9.3.2 Calculation of the parameterized shutdown time .74
9.4 Duration of demands .78
9.5 Constraints for calculation of system characteristics.78
9.5.1 System characteristics.78
9.5.2 Calculation of the number of telegrams per second .78
9.6 Maintenance.79
9.7 Safety manual .80
10 Assessment.80
Annex A (informative) Additional information for functional safety communication
profiles of CPF 6.81
Annex B (informative) Information for assessment of the functional safety
communication profiles of CPF 6 .82
Bibliography.83

Table 1 – Overview of profile identifier usable for FSCP 6/7.22
Table 2 – Selection of the various measures for possible errors.23
Table 3 – List of function blocks and subsystems.27
Table 4 – Signal flow between the function blocks .29
Table 5 – Initiate service parameters .38
Table 6 – Parameterization mode and related services .39
Table 7 – Abort service parameters .39
Table 8 – Abort of a point-to-point connection by the SRP or SRC .40
Table 9 – Send application parameter service.40
Table 10 – Send application parameter ID service .41
Table 11 – Parameterize device parameters .42
Table 12 – Transmit-Safety-Data service parameters.43
Table 13 – Set-Diagnostic-Data service parameters.44
Table 14 – Set-Acknowledgement-Data service parameters.45
Table 15 – Parameter ID.48
Table 16 – Block 0: Device ID.48
Table 17 – Block 1: Parameter record ID .49
Table 18 – Block 2: Application parameter .50
Table 19 – TIME encoding .52
Table 20 – Abort_Info: Connection abort in the event of an error detected by the SCLM .68
Table 21 – Abort_Info: Abort of all connections in the event of an error detected by the
SCLS .69
Table 22 – Abort_Info: Abort of all connections in the event of an error detected by the
SCLM .71
Table 23 – Set-Safety-Configuration service .72
Table 24 – Error_Info.72
Table 25 – Calculation of tIB.77
Table 26 – Calculation of tSRC .78

61784-3-6 © IEC:2010(E) – 5 –
Table 27 – Calculation of tPST .78

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 – FSCP 6/7 communication preconditions .21
Figure 4 – Example of a safety function .25
Figure 5 – Decomposition of safety function into function blocks.26
Figure 6 – Overview of the results of the decomposition process .28
Figure 7 – Signal flow between the function blocks .28
Figure 8 – Interfaces between the safety devices within the safety communication
system .29
Figure 9 – Signal flow and safe states .31
Figure 10 – Mapping of the Safe Transmission function block .33
Figure 11 – Relationship between SCL and the other layers of IEC 61158 Type 8.34
Figure 12 – Use of the AR-US service to initiate and parameterize .35
Figure 13 – Use of the AR-US service to transmit safety data .35
Figure 14 – Use of the AR-US service to abort.36
Figure 15 – Use of the AR-US service to abort.36
Figure 16 – Structure of the safety PDU.45
Figure 17 – Integration of safety data and deterministic remedial measures in the
summation frame .46
Figure 18 – Write_Parameter_Byte_Req message .47
Figure 19 – Read_Parameter_Byte_Req message .47
Figure 20 – Parameter_Byte_Con message .47
Figure 21 – Set_Safety_Connection_ID_Req message .50
Figure 22 – Set_Safety_Connection_ID_Con message of safety slaves .50
Figure 23 – Parameter_Idle_Req .51
Figure 24 – Parameter_Idle_Con .51
Figure 25 – Parameter_Check_Con .51
Figure 26 – Parameter_Loc_ID_Changed_Con .51
Figure 27 – Transmit Safety Data Message.52
Figure 28 – Sync_a message of the SCLM.53
Figure 29 – Req_b message of the SCLM .53
Figure 30 – Req_c message of the SCLM .53
Figure 31 – Req_d message of the SCLM .54
Figure 32 – Abort_Connection message .54
Figure 33 – Safety-Slave_Error message.54
Figure 34 – SCLM state machine .55
Figure 35 – SCLS state machine.55
Figure 36 – Initiate sequence.56
Figure 37 – Send Application Parameter sequence .58
Figure 38 – Send Application Parameter ID sequence .59
Figure 39 – Parameterize device sequence.60

– 6 – 61784-3-6 © IEC:2010(E)
Figure 40 – Simultaneous transmission of safety data to the safety slaves.61
Figure 41 – Use of the sequence number in the SCLM and SCLS .62
Figure 42 – Startup and error-free operation .63
Figure 43 – Resynchronization during operation .64
Figure 44 – Invalid CRC 24 checksum detected by the SCLS.65
Figure 45 – Process data mode with diagnostic data transmission .66
Figure 46 – Process data mode with Acknowledgement-Data transmission .67
Figure 47 – Error when initiating a connection .68
Figure 48 – Error at an SCLS when aborting all connections.69
Figure 49 – Abort of all connections in the event of an error detected by the SCLM .70
Figure 50 – Overview of the shutdown time.75

61784-3-6 © IEC:2010(E) – 7 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
INDUSTRIAL COMMUNICATION NETWORKS –
PROFILES –
Part 3-6: Functional safety fieldbuses –
Additional specifications for CPF 6

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 61784-3-6 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 2007. This edition
constitutes a technical revision. The main changes with respect to the previous edition are
listed below:
⎯ updates in relation with changes in IEC 61784-3.

– 8 – 61784-3-6 © IEC:2010(E)
The text of this standard is based on the following documents:
FDIS Report on voting
65C/591A/FDIS 65C/603/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.
61784-3-6 © IEC:2010(E) – 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 many fieldbus enhancements are emerging, addressing not yet standardized
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.
Product standards
ISO 12100-1 and ISO 14121
ISO 12100-1 and ISO 14121
IEC 61496 IEC 61800-5-2 ISO 10218-1 Safety of machinery – Principles for
IEC 61131-6
IEC 61496 IEC 61131-6 IEC 61800-5-2 ISO 10218-1 Safety of machinery – Principles for
Safety f. e.g. Safety functions Safety requirements design and risk assessment
Safety for PLC design and risk assessment
Safety f. e.g. Safety for PLC Safety functions Safety requirements
light curtains (under consideration) for drives for robots
(under consideration)
light curtains for drives for robots
Design of safety-related electrical, electronic and program-
IEC 61784-4 IEC 62443
IEC 61784-4 IEC 62443
Security Security mable electronic control systems (SRECS) for machinery
Security Security
(profile-specific) (common part)
(profile-specific) (common part)
SIL based PL based
IEC 61784-5 IEC 61918
IEC 61784-5 IEC 61918
Installation guide Installation guide
Installation guide Installation guide Design objective
(profile-specific) (common part)
(profile-specific) (common part)
Applicable standards
ISO 13849-1, -2
ISO 13849-1, -2
IEC 60204-1
IEC 60204-1
Safety-related parts
Safety-related parts
Safety of electrical
Safety of electrical
IEC 61000-1-2
IEC 61000-1-2 of machinery
of machinery
equipment
equipment
Methodology EMC & FS
Methodology EMC & FS (SRPCS)
(SRPCS)
IEC 61326-3-1
IEC 61784-3
IEC 61784-3 IEC 61326-3-1
Non-electrical
Non-electrical
Functional safety Test EMC & FS
Functional safety Test EMC & FS
communication
communication
Electrical
Electrical
US: NFPA 79
US: NFPA 79
profiles
profiles
(2006)
(2006)
IEC 62061
IEC 62061
Functional safety
Functional safety
IEC 61158 series /
IEC 61158 series /
for machinery
for machinery
IEC 61784-1, -2 IEC 61508 series
IEC 61784-1, -2 IEC 61508 series (SRECS)
(SRECS)
Functional safety (FS)
Fieldbus for use in Functional safety (FS) (including EMC for
Fieldbus for use in (including EMC for
(basic standard)
(basic standard) industrial environment)
industrial control systems industrial environment)
industrial control systems
Key
(yellow) safety-related standards
(blue) fieldbus-related standards
(dashed yellow) this standard
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)

– 10 – 61784-3-6 © IEC:2010(E)
Figure 2 shows the relationships between this standard and relevant safety and fieldbus
standards in a process environment.
Product standards
IEC 61496 IEC 61800-5-2 ISO 10218-1
IEC 61131-6
IEC 61496 IEC 61131-6 IEC 61800-5-2 ISO 10218-1
Safety f. e.g. Safety functions Safety requirements
Safety for PLC
Safety f. e.g. Safety for PLC Safety functions Safety requirements
light curtains (under consideration) for drives for robots
(under consideration)
light curtains for drives for robots
IEC 61784-4 IEC 62443
IEC 61784-4 IEC 62443
Security Security
Security Security
(profile-specific) (common part)
(profile-specific) (common part)
See safety standards for machinery
(Figure 1)
IEC 61784-5 IEC 61918
IEC 61784-5 IEC 61918
Installation guide Installation guide
Installation guide Installation guide
(profile-specific) (common part)
(profile-specific) (common part)
Valid also in process industries,
whenever applicable
a)
a)
IEC 61326-3-2
IEC 61326-3-2
EMC and
EMC and
functional safety
functional safety
IEC 61784-3
IEC 61784-3
Functional safety
Functional safety
communication
communication
profiles
profiles
US:
US:
ISA-84.00.01
ISA-84.00.01
b)
b)
(3 parts = modified
IEC 61511 series
IEC 61511 series (3 parts = modified
IEC 61511)
Functional safety –
IEC 61158 series / Functional safety – IEC 61511)
IEC 61158 series /
Safety instrumented
Safety instrumented
IEC 61784-1, -2 IEC 61508 series
IEC 61784-1, -2 IEC 61508 series
systems for the
systems for the
Fieldbus for use in Functional safety (FS)
Functional safety (FS)
Fieldbus for use in DE: VDI 2180
process industry sector DE: VDI 2180
process industry sector
(basic standard)
(basic standard)
industrial control systems Part 1-4
industrial control systems
Part 1-4
Key
(yellow) safety-related standards
(blue) fieldbus-related standards
(dashed yellow) this standard
a
For specified electromagnetic environments; otherwise IEC 61326-3-1.
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 within this system – implementation of a functional safety
communication profile in a standard device is not sufficient to qualify it as a safety device.

61784-3-6 © IEC:2010(E) – 11 –
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;
⎯ individual description of functional safety profiles for several communication profile
families in IEC 61784-1 and IEC 61784-2;
⎯ 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 patents concerning the
functional safety communication profiles for family 6 as follows, where the [xx] notation
indicates the holder of the patent right:
DE 103 25 263 A1 [PxC] Sicherstellung von maximalen Reaktionszeiten in
komplexen oder verteilten sicheren und/oder nicht
sicheren Systemen
DE 103 18 068 A1 [PxC] Verfahren und Vorrichtung zum Paket-orientierten
Übertragen sicherheitsrelevanter Daten
IEC takes no position concerning the evidence, validity and scope of these patent rights.
The holders of these patents rights have assured the IEC that they are willing to negotiate
licences under reasonable and non-discriminatory terms and conditions with applicants
throughout the world. In this respect, the statement of the holders of these patent rights
...