IEC 61784-3-3:2016

IEC 61784-3-3 ®
Edition 3.0 2016-07
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Industrial communication networks – Profiles –
Part 3-3: Functional safety fieldbuses – Additional specifications for CPF 3

Réseaux de communication industriels – Profils –
Partie 3-3: Bus de terrain de sécurité fonctionnelle – Spécifications
supplémentaires pour CPF 3
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IEC 61784-3-3 ®
Edition 3.0 2016-07
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Industrial communication networks – Profiles –

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

Réseaux de communication industriels – Profils –

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

supplémentaires pour CPF 3
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 25.040.40, 35.100.05 ISBN 978-2-8322-3481-5

– 2 – IEC 61784-3-3:2016  IEC 2016
CONTENTS
FOREWORD . 8
0 Introduction . 10
0.1 General . 10
0.2 Patent declaration . 12
1 Scope . 14
2 Normative references. 14
3 Terms, definitions, symbols, abbreviated terms and conventions. 16
3.1 Terms and definitions . 16
3.1.1 Common terms and definitions . 16
3.1.2 CPF 3: Additional terms and definitions . 22
3.2 Symbols and abbreviated terms . 26
3.2.1 Common symbols and abbreviated terms . 26
3.2.2 CPF 3: Additional symbols and abbreviated terms . 27
3.3 Conventions . 28
4 Overview of FSCP 3/1 (PROFIsafe™) . 28
5 General . 31
5.1 External documents providing specifications for the profile . 31
5.2 Safety functional requirements . 31
5.3 Safety measures . 31
5.4 Safety communication layer structure . 32
5.4.1 Principle of FSCP 3/1 safety communications . 32
5.4.2 CPF 3 communication structures . 33
5.5 Relationships with FAL (and DLL, PhL) . 36
5.5.1 Device model . 36
5.5.2 Application and communication relationships . 37
5.5.3 Data types . 37
6 Safety communication layer services . 38
6.1 F-Host services . 38
6.2 F-Device services. 41
6.3 Diagnosis . 43
6.3.1 Safety alarm generation . 43
6.3.2 F-Device safety layer diagnosis including the iPar-Server . 43
7 Safety communication layer protocol . 44
7.1 Safety PDU format . 44
7.1.1 Safety PDU structure . 44
7.1.2 Safety IO data . 45
7.1.3 Status and Control Byte . 45
7.1.4 (Virtual) MonitoringNumber . 47
7.1.5 (Virtual) MNR mechanism (F_CRC_Seed=0) . 48
7.1.6 (Virtual) MNR mechanism (F_CRC_Seed=1) . 48
7.1.7 CRC2 Signature (F_CRC_Seed=0) . 50
7.1.8 CRC2 Signature (F_CRC_Seed=1) . 51
7.1.9 Non-safety IO data . 52
7.2 FSCP 3/1 behavior . 52
7.2.1 General . 52

7.2.2 F-Host state diagram . 53
7.2.3 F-Device state diagram . 56
7.2.4 Sequence diagrams . 60
7.2.5 Timing diagram for a MonitoringNumber reset . 66
7.2.6 Monitoring of safety times . 66
7.3 Reaction in the event of a malfunction . 69
7.3.1 Unintended repetition . 69
7.3.2 Loss . 70
7.3.3 Insertion . 70
7.3.4 Incorrect sequence . 70
7.3.5 Corruption of safety data . 70
7.3.6 Unacceptable delay . 70
7.3.7 Masquerade . 70
7.3.8 Addressing. 71
7.3.9 Memory failures within switches . 71
7.3.10 Loop-back . 72
7.3.11 Network boundaries and router . 72
7.4 F-Startup and parameter change at runtime . 73
7.4.1 Standard startup procedure . 73
7.4.2 iParameter assignment deblocking . 73
8 Safety communication layer management . 73
8.1 F-Parameter . 73
8.1.1 Summary . 73
8.1.2 F_Source/Destination_Address (Codename) . 74
8.1.3 F_WD_Time (F-Watchdog time) . 74
8.1.4 F_WD_Time_2 (secondary F-Watchdog time) . 75
8.1.5 F_Prm_Flag1 (Parameters for the safety layer management) . 75
8.1.6 F_Prm_Flag2 (Parameters for the safety layer management) . 77
8.1.7 F_iPar_CRC (value of iPar_CRC across iParameters) . 78
8.1.8 F_Par_CRC calculation (across F-Parameters) . 79
8.1.9 Structure of the F-Parameter record data object . 79
8.2 iParameter and iPar_CRC . 79
8.3 Safety parameterization. 80
8.3.1 Objectives . 80
8.3.2 GSDL and GSDML safety extensions . 81
8.3.3 Securing safety parameters and GSD data . 83
8.4 Safety configuration . 87
8.4.1 Securing the safety IO data description (CRC7) . 87
8.4.2 DataItem data type section examples . 88
8.5 Data type information usage . 92
8.5.1 F-Channel driver . 92
8.5.2 Rules for standard F-Channel drivers . 93
8.5.3 Recommendations for F-Channel drivers . 94
8.6 Safety parameter assignment mechanisms . 95
8.6.1 F-Parameter assignment . 95
8.6.2 General iParameter assignment . 95
8.6.3 System integration requirements for iParameterization tools . 96
8.6.4 iPar-Server . 98
9 System requirements . 107

– 4 – IEC 61784-3-3:2016  IEC 2016
9.1 Indicators and switches . 107
9.2 Installation guidelines . 107
9.3 Safety function response time . 107
9.3.1 Model . 107
9.3.2 Calculation and optimization . 109
9.3.3 Adjustment of watchdog times for FSCP 3/1 . 111
9.3.4 Engineering tool support . 112
9.3.5 Retries (repetition of messages) . 112
9.4 Duration of demands . 113
9.5 Constraints for the calculation of system characteristics . 114
9.5.1 Probabilistic considerations . 114
9.5.2 Safety related assumptions . 116
9.5.3 Non safety related constraints (availability) . 117
9.6 Maintenance . 117
9.6.1 F-Module commissioning / replacement . 117
9.6.2 Identification and maintenance functions . 117
9.7 Safety manual . 117
9.8 Wireless transmission channels . 119
9.8.1 Black channel approach . 119
9.8.2 Availability . 119
9.8.3 Security measures . 119
9.8.4 Stationary and mobile applications . 122
9.9 Conformance classes . 122
10 Assessment . 124
10.1 Safety policy . 124
10.2 Obligations. 124
Annex A (informative) Additional information for functional safety communication
profiles of CPF 3 . 126
A.1 Hash function calculation . 126
A.2 Example values for MonitoringNumbers (MNR) . 129
A.3 Response time measurements . 130
Annex B (informative) Information for assessment of the functional safety
communication profiles of CPF 3 . 133
Bibliography . 134

Figure 1 – Relationships of IEC 61784-3 with other standards (machinery) . 10
Figure 2 – Relationships of IEC 61784-3 with other standards (process) . 11
Figure 3 – Basic communication preconditions for FSCP 3/1 . 29
Figure 4 – Structure of an FSCP 3/1 safety PDU. 29
Figure 5 – Safety communication on CPF 3 . 30
Figure 6 – Standard CPF 3 transmission system . 32
Figure 7 – Safety layer architecture . 33
Figure 8 – Basic communication layers . 34
Figure 9 – Multiport switch bus structure . 34
Figure 10 – Linear bus structure . 35
Figure 11 – Crossing network borders with routers . 35
Figure 12 – Complete safety transmission paths . 36

Figure 13 – IO Device model . 37
Figure 14 – FSCP 3/1 communication structure . 38
Figure 15 – F user interface of F-Host driver instances . 39
Figure 16 – Motivation for "Channel-related Passivation" . 40
Figure 17 – F-Device driver interfaces . 42
Figure 18 – Safety PDU for CPF 3 . 45
Figure 19 – Status Byte . 45
Figure 20 – Control Byte . 46
Figure 21 – The Toggle Bit function . 47
Figure 22 – F-Device MonitoringNumber . 48
Figure 23 – F-Host CRC2 signature generation (F_CRC_Seed=0) . 50
Figure 24 – Details of the CRC2 signature calculation (F_CRC_Seed=0) . 51
Figure 25 – CRC2 signature calculation (F_CRC_Seed=1) . 51
Figure 26 – Details of the CRC2 signature calculation (F_CRC_Seed=1) . 52
Figure 27 – Safety layer communication relationship . 52
Figure 28 – F-Host state diagram . 53
Figure 29 – F-Device state diagram . 57
Figure 30 – Interaction F-Host / F-Device during start-up . 60
Figure 31 – Interaction F-Host / F-Device during F-Host power off → on . 61
Figure 32 – Interaction F-Host / F-Device with delayed power on . 62
Figure 33 – Interaction F-Host / F-Device during power off → on . 63
Figure 34 – Interaction F-Host / F-Device while host recognizes CRC error . 64
Figure 35 – Interaction F-Host / F-Device while device recognizes CRC error . 65
Figure 36 – Impact of the MNR reset signal . 66
Figure 37 – Monitoring the message transit time F-Host ↔ F-Output . 67
Figure 38 – Monitoring the message transit time F-Input ↔ F-Host . 67
Figure 39 – Extended watchdog time on request . 69
Figure 40 – iParameter assignment deblocking by the F-Host . 73
Figure 41 – Effect of F_WD_Time_2 . 75
Figure 42 – F_Prm_Flag1. 75
Figure 43 – F_Check_SeqNr . 76
Figure 44 – F_Check_iPar. 76
Figure 45 – F_SIL . 76
Figure 46 – F_CRC_Length . 77
Figure 47 – F_CRC_Seed . 77
Figure 48 – F_Prm_Flag2. 77
Figure 49 – F_Passivation . 78
Figure 50 – F_Block_ID . 78
Figure 51 – F_Par_Version . 78
Figure 52 – F-Parameter . 79
Figure 53 – iParameter block . 80
Figure 54 – F-Parameter extension within the GSDML specification . 82
Figure 55 – F_Par_CRC signature including iPar_CRC . 84

– 6 – IEC 61784-3-3:2016  IEC 2016
Figure 56 – Algorithm to build CRC0 . 84
Figure 57 – GSD example in GSDML notation . 86
Figure 58 – DataItem section for F_IN_OUT_1 . 89
Figure 59 – DataItem section for F_IN_OUT_2 . 90
Figure 60 – DataItem section for F_IN_OUT_5 . 91
Figure 61 – DataItem section for F_IN_OUT_6 . 92
Figure 62 – F-Channel driver as "glue" between F-Device and user program . 93
Figure 63 – Layout example of an F-Channel driver . 94
Figure 64 – F-Parameter assignment for simple F-Devices and F-Slaves . 95
Figure 65 – F and iParameter assignment for complex F-Devices . 96
Figure 66 – System integration of CPD-Tools . 97
Figure 67 – iPar-Server mechanism (commissioning) . 98
Figure 68 – iPar-Server mechanism (for example F-Device replacement) . 99
Figure 69 – iPar-Server request coding ("status model") . 100
Figure 70 – Coding of SR_Type . 101
Figure 71 – iPar-Server request coding ("alarm model") . 102
Figure 72 – iPar-Server state diagram . 104
Figure 73 – Example safety function with a critical response time path . 108
Figure 74 – Simplified typical response time model . 108
Figure 75 – Frequency distributions of typical response times of the model . 109
Figure 76 – Context of delay times and watchdog times . 110
Figure 77 – Timing sections forming the FSCP 3/1 F_WD_Time . 111
Figure 78 – Frequency distribution of response times with message retries . 112
Figure 79 – Retries with CP 3/1 . 113
Figure 80 – Retries with CP 3/RTE . 113
Figure 81 – Residual error probabilities for the 24-bit CRC polynomial . 114
Figure 82 – Residual error probabilities for the 32-bit CRC polynomial . 115
Figure 83 – Monitoring of corrupted messages . 116
Figure 84 – Considerations against systematic loop-back configuration errors . 119
Figure 85 – Security for WLAN networks . 120
Figure 86 – Security for Bluetooth networks . 121
Figure A.1 – Typical "C" procedure of a cyclic redundancy check . 126
Figure A.2 – Comparison of the response time model and a real application . 130
Figure A.3 – Frequency distribution of measured response times . 131
Figure A.4 – F-Host with standard and safety-related application programs . 132

Table 1 – Deployed measures to master errors . 32
Table 2 – Data types for FSCP 3/1 . 37
Table 3 – Safety layer diagnosis messages . 44
Table 4 – MonitoringNumber of an F-Host PDU . 48
Table 5 – MonitoringNumber of an F-Device PDU . 48
Table 6 – MonitoringNumber of an F-Host PDU . 49
Table 7 – MonitoringNumber of an F-Device PDU . 49

Table 8 – Definition of terms used in F-Host state diagram . 54
Table 9 – F-Host states and transitions . 54
Table 10 – Definition of terms used in Figure 29 . 57
Table 11 – F-Device states and transitions . 58
Table 12 – SIL monitor times. 69
Table 13 – Remedies for switch failures . 71
Table 14 – Safety network boundaries . 72
Table 15 – Codename octet order . 74
Table 16 – GSDL keywords for F-Parameters and F-IO structures . 81
Table 17 – GSD example in GSDL notation . 85
Table 18 – Serialized octet stream for the examples . 86
Table 19 – IO data structure items . 87
Table 20 – Sample F-Channel drivers . 93
Table 21 – Requirements for iParameterization . 96
Table 22 – Specifier for the iPar-Server Request . 101
Table 23 – Structure of the Read_RES_PDU ("read record") . 102
Table 24 – Structure of the Write_REQ_PDU ("write record") . 103
Table 25 – Structure of the Pull_RES_PDU ("Pull") . 103
Table 26 – Structure of the Push_REQ_PDU ("Push") . 103
Table 27 – iPar-Server states and transitions . 105
Table 28 – iPar-Server management measures . 106
Table 29 – Definition of terms in Figure 83 . 116
Table 30 – Information to be included in the safety manual . 118
Table 31 – Definition of terms in Figure 85 . 120
Table 32 – Security measures for WLAN (IEEE 802.11) . 120
Table 33 – Definition of terms in Figure 86 . 121
Table 34 – Security measures for Bluetooth (IEEE 802.15.1) . 122
Table 35 – F-Host conformance class requirements . 122
Table 36 – Main characteristics of protocol versions . 124
Table 37 – F-Host/F-Device conformance matrix . 124
Table A.1 – The table "Crctab24" for 24 bit CRC signature calculations . 127
Table A.2 – The table "Crctab32" for 32 bit CRC signature calculations . 128
Table A.3 – The table "Crctab16" for 16 bit CRC signature calculations . 129
Table A.4 – Values of CN_incrNR_64 and MNR for F-Host PDU . 130

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

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
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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 61784-3-3 has been prepared by subcommittee 65C: Industrial
networks, of IEC technical committee 65: Industrial-process measurement, control and
automation.
This third edition cancels and replaces the second edition published in 2010. This edition
constitutes a technical revision. This edition includes the following significant technical
changes with respect to the previous edition:
• Legacy V1-mode removed from this protocol edition;
• Protocol extensions to protect against possible loopbacks (LP extensions);
• Protocol extensions to keep SIL3 for safety networks with large numbers of participants
(XP extensions) and subsequent new F-Parameter "F_CRC_Seed";
• Introduction of random and disjoint Codename based MonitoringNumbers (MNR) besides
to the previous Consecutive Numbers;

• Provisions for Channel Granular Passivation and subsequent new F-Parameter
"F_Passivation";
• GSD extensions due to new F-Parameters;
• Notations according to the CP3 family in IEC 61158 (e.g. IO Controller);
• Additional diagnosis message types;
• Diverse error corrections and fixes of typos;
• Updated documents in bibliography.
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.
– 10 – IEC 61784-3-3:2016  IEC 2016
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.
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 erro
...