EN IEC 61784-2-12:2023

Industrial networks - Profiles - Part 2-12: Additional real-time fieldbus profiles based on ISO/IEC/IEEE 8802-3 - CPF 12

IEC 61784-2-12:2023 defines Communication Profile Family 12 (CPF 12). CPF 12 specifies a set of Real-Time Ethernet (RTE) communication profiles (CPs) and related network components based on the IEC 61158 series (Type 12), ISO/IEC/IEEE 8802-3 and other standards. For each RTE communication profile, this document also specifies the relevant RTE performance indicators and the dependencies between these RTE performance indicators. NOTE 1 All CPs are based on standards or draft standards or International Standards published by the IEC or on standards or International Standards established by other standards bodies or open standards processes. NOTE 2 The RTE communication profiles use ISO/IEC/IEEE 8802-3 communication networks and its related network components and in some cases amend those standards to obtain RTE features.

Industrielle Kommunikationsnetze - Profile - Teil 2-12: Zusätzliche Feldbusprofile für Echtzeitnetzwerke basierend auf ISO/IEC/IEEE 8802-3 - Kommunikationsprofilfamilie (CPF) 12

Réseaux industriels – Profils – Partie 2-12: Profils de bus de terrain supplémentaires pour les réseaux en temps réel fondés sur l’ISO/IEC/IEEE 8802-3 – CPF 12

L’IEC 61784-2-12:2023 définit la famille de profils de communication 12 (CPF 12). La CPF 12 spécifie un ensemble de profils de communication (CP) Ethernet en temps réel (RTE, Real-Time Ethernet) et de composants de réseau associés basés sur la série IEC 61158 (type 12), l’ISO/IEC/IEEE 8802-3 et d’autres normes. Pour chaque profil de communication RTE, le présent document spécifie également les indicateurs de performance RTE correspondants et les dépendances entre ces indicateurs de performance RTE. NOTE 1 Tous les CP sont fondés sur des normes ou projets de normes, ou des Normes internationales, publiés par l’IEC, ou bien sur des normes ou des Normes internationales établies par d’autres organismes de normalisation ou des processus de normalisation ouverts. NOTE 2 Les profils de communication RTE utilisent les réseaux de communication ISO/IEC/IEEE 8802-3 et leurs composants de réseau connexes et amendent dans certains cas ces normes, pour obtenir les fonctions RTE.

Industrijska omrežja - Profili - 2-12. del: Dodatni profili procesnih vodil v realnem času po ISO/IEC/IEEE 8802-3 - CPF 12 (IEC 61784-2-12:2023)

Standard IEC 61784-2-12:2023 določa družino komunikacijskih profilov 12 (CPF 12). Družina komunikacijskih profilov 12 določa sklop komunikacijskih profilov (CP) Real-Time Ethernet (RTE) in povezanih omrežnih komponent na osnovi skupine standardov IEC 61158 (tip 12), standarda ISO/IEC/IEEE 8802-3 in drugih standardov.
Za vsak komunikacijski profil RTE ta dokument določa tudi povezane kazalnike uspešnosti RTE in odvisnosti med temi kazalniki uspešnosti RTE.
OPOMBA 1: Vsi komunikacijski profili temeljijo na standardih ali osnutkih standardov ali mednarodnih standardih, ki jih je objavila komisija IEC, oziroma na standardih ali mednarodnih standardih, ki so jih določili drugi organi za standarde ali procesi odprtih standardov.
OPOMBA 2: Komunikacijski profili RTE uporabljajo komunikacijska omrežja v skladu s standardom ISO/IEC 8802-3 in z njimi povezane omrežne komponente ter v nekaterih primerih za pridobitev funkcij RTE te standarde spremenijo.

General Information

• Status: Published
• Publication Date: 15-Jun-2023
• ICS: 35.100.20 - Data link layer
• ICS: 35.240.50 - IT applications in industry
• Technical Committee: CLC/TC 65X - Industrial-process measurement, control and automation
• Current Stage: 6060 - Document made available - Publishing
• Start Date: 16-Jun-2023
• Completion Date: 16-Jun-2023
• Ref Project: SIST EN IEC 61784-2-12:2023 - Industrial networks - Profiles - Part 2-12: Additional real-time fieldbus profiles based on ISO/IEC/IEEE 8802-3 - CPF 12 (IEC 61784-2-12:2023)

Relations

• Splited From: EN IEC 61784-2:2019 - Industrial communication networks - Profiles - Part 2: Additional fieldbus profiles for real-time networks based on ISO/IEC/IEEE 8802-3
• Effective Date: 30-May-2023

Standards Content (Sample)

SLOVENSKI STANDARD
01-november-2023
Industrijska omrežja - Profili - 2-12. del: Dodatni profili procesnih vodil v realnem
času po ISO/IEC/IEEE 8802-3 - CPF 12 (IEC 61784-2-12:2023)
Industrial networks - Profiles - Part 2-12: Additional real-time fieldbus profiles based on
ISO/IEC/IEEE 8802-3 - CPF 12 (IEC 61784-2-12:2023)
Industrielle Kommunikationsnetze - Profile - Teil 2-12: Zusätzliche Feldbusprofile für
Echtzeitnetzwerke basierend auf ISO/IEC/IEEE 8802-3 - Kommunikationsprofilfamilie
(CPF) 12 (IEC 61784-2-12:2023)
Réseaux industriels - Profils - Partie 2-12: Profils de bus de terrain supplémentaires pour
les réseaux en temps réel fondés sur l'ISO/IEC/IEEE 8802-3 - CPF 12 (IEC 61784-2-
12:2023)
Ta slovenski standard je istoveten z: EN IEC 61784-2-12:2023
ICS:
25.040.40 Merjenje in krmiljenje Industrial process
industrijskih postopkov measurement and control
35.100.05 Večslojne uporabniške Multilayer applications
rešitve
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN IEC 61784-2-12

NORME EUROPÉENNE
EUROPÄISCHE NORM June 2023
ICS 35.100.20; 35.240.50 Supersedes EN IEC 61784-2:2019 (partially)
English Version
Industrial networks - Profiles - Part 2-12: Additional real-time
fieldbus profiles based on ISO/IEC/IEEE 8802-3 - CPF 12
(IEC 61784-2-12:2023)
Réseaux industriels - Profils - Partie 2-12: Profils de bus de Industrielle Kommunikationsnetze - Profile - Teil 2-12:
terrain supplémentaires pour les réseaux en temps réel Zusätzliche Feldbusprofile für Echtzeitnetzwerke basierend
fondés sur l'ISO/IEC/IEEE 8802-3 - CPF 12 auf ISO/IEC/IEEE 8802-3 - Kommunikationsprofilfamilie
(IEC 61784-2-12:2023) (CPF) 12
(IEC 61784-2-12:2023)
This European Standard was approved by CENELEC on 2023-06-09. 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,
Türkiye 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
© 2023 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN IEC 61784-2-12:2023 E

European foreword
The text of document 65C/1209/FDIS, future edition 1 of IEC 61784-2-12, 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
The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2024-03-09
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2026-06-09
document have to be withdrawn
This document partially supersedes EN IEC 61784-2:2019 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.
Any feedback and questions on this document should be directed to the users’ national committee. A
complete listing of these bodies can be found on the CENELEC website.
Endorsement notice
The text of the International Standard IEC 61784-2-12:2023 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 standard indicated:
IEC 61158-1 NOTE Approved as EN IEC 61158-1
IEC 61784-1 (series) NOTE Approved as EN IEC 61784-1 (series)
IEC 61784-1-0 NOTE Approved as EN IEC 61784-1-0
IEC 61784-2 (series) NOTE Approved as EN IEC 61784-2 (series)
IEC 61918 NOTE Approved as EN IEC 61918
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.cencenelec.eu.
Publication Year Title EN/HD Year
IEC 61158 series Industrial communication networks - EN IEC 61158 series
Fieldbus specifications
IEC 61158-2 2023 Industrial communication networks - EN IEC 61158-2 2023
Fieldbus specifications - Part 2: Physical
layer specification and service definition
IEC 61158-3-12 2019 Industrial communication networks - EN IEC 61158-3-12 2019
Fieldbus specifications - Part 3-12: Data-
link layer service definition - Type 12
elements
IEC 61158-4-12 2019 Industrial communication networks - EN IEC 61158-4-12 2019
Fieldbus specifications - Part 4-12: Data-
link layer protocol specification - Type 12
elements
IEC 61158-5-12 2019 Industrial communication networks - EN IEC 61158-5-12 2019
Fieldbus specifications - Part 5-12:
Application layer service definition - Type
12 elements
IEC 61158-6-12 2019 Industrial communication networks - EN IEC 61158-6-12 2019
Fieldbus specifications - Part 6-12:
Application layer protocol specification -
Type 12 elements
IEC 61784-2-0 2023 Industrial networks - Profiles - Part 2-0: EN IEC 61784-2-0 2023
Additional real-time fieldbus profiles based
on ISO/IEC/IEEE 8802-3 - General
concepts and terminology
ISO/IEC/IEEE 8802-3 2021 Telecommunications and exchange - -
between information technology systems -
Requirements for local and metropolitan
area networks - Part 3: Standard for
Ethernet
IETF RFC 791 1981 Internet Protocol - -

IEC 61784-2-12 ®
Edition 1.0 2023-05
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Industrial networks – Profiles –
Part 2-12: Additional real-time fieldbus profiles based on ISO/IEC/IEEE 8802-3 –
CPF 12
Réseaux industriels – Profils –
Partie 2-12: Profils de bus de terrain supplémentaires pour les réseaux en
temps réel fondés sur l’ISO/IEC/IEEE 8802-3 – CPF 12
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 35.100.20; 35.240.50 ISBN 978-2-8322-6900-8
– 2 – IEC 61784-2-12:2023 © IEC 2023
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms, definitions, abbreviated terms, acronyms, and conventions . 8
3.1 Terms and definitions . 8
3.2 Abbreviated terms and acronyms . 8
3.3 Symbols . 8
3.4 Conventions . 8 ®
4 CPF 12 (EtherCAT ) – RTE communication profiles . 9
4.1 General overview . 9
4.2 CP 12/1 . 9
4.2.1 Physical layer . 9
4.2.2 Data-link layer . 11
4.2.3 Application layer . 14
4.2.4 Performance indicator selection . 17
4.3 CP 12/2 . 20
4.3.1 Physical layer . 20
4.3.2 Data-link layer . 20
4.3.3 Application layer . 24
4.3.4 Performance indicator selection . 26
Bibliography . 29

Table 1 – CPF 12 symbols . 8
Table 2 – CP 12/1: PhL selection of physical layer from ISO/IEC/IEEE 8802-3:2021 . 9
Table 3 – CP 12/1: PhL selection of a power integrated physical layer from
IEC 61158-2 . 11
Table 4 – CP 12/1: DLL service selection . 11
Table 5 – CP 12/1: DLL protocol selection . 12
Table 6 – CP 12/1: DLL service selection . 13
Table 7 – CP 12/1: DLL protocol selection . 13
Table 8 – CP 12/1: AL service selection . 15
Table 9 – CP 12/1: AL protocol selection . 15
Table 10 – CP 12/1: AL service selection . 16
Table 11 – CP 12/1: AL protocol selection . 17
Table 12 – CP 12/1: PI overview . 17
Table 13 – CP 12/1: PI dependency matrix . 18
Table 14 – CP 12/1: PI ranges . 18
Table 15 – CP 12/1: Consistent set of PIs for mid size automation systems . 20
Table 16 – CP 12/2: DLL service selection . 20
Table 17 – CP 12/2: DLL protocol selection . 21
Table 18 – CP 12/2: DLL service selection . 22
Table 19 – CP 12/2: DLL protocol selection . 23
Table 20 – CP 12/2: AL service selection . 24

IEC 61784-2-12:2023 © IEC 2023 – 3 –
Table 21 – CP 12/2: AL protocol selection . 24
Table 22 – CP 12/2: AL service selection . 25
Table 23 – CP 12/2: AL protocol selection . 26
Table 24 – CP 12/2: PI overview . 27
Table 25 – CP 12/2: PI dependency matrix . 27
Table 26 – CP 12/2: Consistent set of PIs . 28

– 4 – IEC 61784-2-12:2023 © IEC 2023
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
INDUSTRIAL NETWORKS –
PROFILES –
Part 2-12: Additional real-time fieldbus profiles
based on ISO/IEC/IEEE 8802-3 –
CPF 12
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.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of patent
rights. IEC shall not be held responsible for identifying any or all such patent rights.
Attention is drawn to the fact that the use of some of the associated protocol types is restricted
by their intellectual-property-right holders. In all cases, the commitment to limited release of
intellectual-property-rights made by the holders of those rights permits a layer protocol type to
be used with other layer protocols of the same type, or in other type combinations explicitly
authorized by their respective intellectual property right holders.
NOTE Combinations of protocol types are specified in the IEC 61784-1 series and the IEC 61784-2 series.
IEC 61784-2-12 has been prepared by subcommittee 65C: Industrial networks, of IEC technical
committee 65: Industrial-process measurement, control and automation. It is an International
Standard.
This first edition, together with the other parts of the same series, cancels and replaces the
fourth edition of IEC 61784-2 published in 2019. This first edition constitutes a technical revision.

IEC 61784-2-12:2023 © IEC 2023 – 5 –
This edition includes the following significant technical changes with respect to
IEC 61784-2:2019:
a) split of the original IEC 61784-2 into several subparts, one subpart for the material of a
generic nature, and one subpart for each Communication Profile Family specified in the
original document.
The text of this International Standard is based on the following documents:
Draft Report on voting
65C/1209/FDIS 65C/1237/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.
A list of all parts of the IEC 61784-2 series, published under the general title
Industrial networks – Profiles – Part 2: Additional real-time fieldbus profiles based on
ISO/IEC/IEEE 8802-3, can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
– 6 – IEC 61784-2-12:2023 © IEC 2023
INTRODUCTION
The IEC 61784-2 series provides additional Communication Profiles (CP) to the existing
Communication Profile Families (CPF) of the IEC 61784-1 series and additional CPFs with one
or more CPs. These profiles meet the industrial automation market objective of identifying Real-
Time Ethernet (RTE) communication networks coexisting with ISO/IEC/IEEE 8802-3 –
commonly known as Ethernet. These RTE communication networks use provisions of
ISO/IEC/IEEE 8802-3 for the lower communication stack layers and additionally provide more
predictable and reliable real-time data transfer and means for support of precise
synchronization of automation equipment.
More specifically, these profiles help to correctly state the compliance of RTE communication
networks with ISO/IEC/IEEE 8802-3, and to avoid the spreading of divergent implementations.
Adoption of Ethernet technology for industrial communication between controllers and even for
communication with field devices promotes the use of Internet technologies in the field area.
This availability would be unacceptable if it causes the loss of features required in the field area
for industrial communication automation networks, such as:
• real-time,
• synchronized actions between field devices like drives,
• efficient, frequent exchange of very small data records.
These new RTE profiles can take advantage of the improvements of Ethernet networks in terms
of transmission bandwidth and network span.
Another implicit but essential requirement is that the typical Ethernet communication
capabilities, as used in the office world, are fully retained, so that the software involved remains
applicable.
The market is in need of several network solutions, each with different performance
characteristics and functional capabilities, matching the diverse application requirements. RTE
performance indicators, whose values will be provided with RTE devices based on
communication profiles specified in the IEC 61784-2 series, enable the user to match network
devices with application-dependent performance requirements of an RTE network.

IEC 61784-2-12:2023 © IEC 2023 – 7 –
INDUSTRIAL NETWORKS –
PROFILES –
Part 2-12: Additional real-time fieldbus profiles
based on ISO/IEC/IEEE 8802-3 –
CPF 12
1 Scope
This part of IEC 61784-2 defines Communication Profile Family 12 (CPF 12). CPF 12 specifies
a set of Real-Time Ethernet (RTE) communication profiles (CPs) and related network
components based on the IEC 61158 series (Type 12), ISO/IEC/IEEE 8802-3 and other
standards.
For each RTE communication profile, this document also specifies the relevant RTE
performance indicators and the dependencies between these RTE performance indicators.
NOTE 1 All CPs are based on standards or draft standards or International Standards published by the IEC or on
standards or International Standards established by other standards bodies or open standards processes.
NOTE 2 The RTE communication profiles use ISO/IEC/IEEE 8802-3 communication networks and its related
network components and in some cases amend those standards to obtain RTE features.
2 Normative references
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 All parts of the IEC 61158 series, as well as the IEC 61784-1 series and the IEC 61784-2 series, are
maintained simultaneously. Cross-references to these documents within the text therefore refer to the editions as
dated in this list of normative references.
IEC 61158 (all parts), Industrial communication networks – Fieldbus specifications
IEC 61158-2:2023, Industrial communication networks – Fieldbus specifications – Part 2:
Physical layer specification and service definition
IEC 61158-3-12:2019, Industrial communication networks – Fieldbus specifications – Part 3-12:
Data-link layer service definition – Type 12 elements
IEC 61158-4-12:2019, Industrial communication networks – Fieldbus specifications – Part 4-12:
Data-link layer protocol specification – Type 12 elements
IEC 61158-5-12:2019, Industrial communication networks – Fieldbus specifications – Part 5-12:
Application layer service definition – Type 12 elements
IEC 61158-6-12:2019, Industrial communication networks – Fieldbus specifications – Part 6-12:
Application layer protocol specification – Type 12 elements
IEC 61784-2-0:2023, Industrial networks – Profiles – Part 2-0: Additional real-time fieldbus
profiles based on ISO/IEC/IEEE 8802-3 – General concepts and terminology

– 8 – IEC 61784-2-12:2023 © IEC 2023
ISO/IEC/IEEE 8802-3:2021, Telecommunications and exchange between information
technology systems – Requirements for local and metropolitan area networks – Part 3: Standard
for Ethernet
IETF RFC 791, J. Postel, Internet Protocol, September 1981, available at
https://www.rfc-editor.org/info/rfc791 [viewed 2022-02-18]
3 Terms, definitions, abbreviated terms, acronyms, and conventions
3.1 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 61784-2-0 and
ISO/IEC/IEEE 8802-3 apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at https://www.electropedia.org/
• ISO Online browsing platform: available at https://www.iso.org/obp
3.2 Abbreviated terms and acronyms
For the purposes of this document, abbreviated terms and acronyms defined in IEC 61784-2-0
and the following apply.
CP Communication Profile [according to IEC 61784-1-0]
CPF Communication Profile Family [according to IEC 61784-1-0]
IETF Internet Engineering Task Force
IP Internet Protocol (see IETF RFC 791)
NoS Number of Switches
PI Performance indicator
3.3 Symbols
For the purposes of this document, symbols defined in IEC 61784-2-0 and Table 1 apply.
Table 1 – CPF 12 symbols
Symbol Definition Unit
l Total cable length m
tc
NoS Number of slaves –
Pd Propagation delay µs
t Cable delay µs/m
cd
t Data copy delay within a slave µs
cpdl
t Cycle time µs
cycle
t Delivery time µs
D
t Time to transmit the longest real-time Ethernet frame µs
data
3.4 Conventions
For the purposes of this document, the conventions defined in IEC 61784-2-0 apply.

IEC 61784-2-12:2023 © IEC 2023 – 9 – ®
4 CPF 12 (EtherCAT ) – RTE communication profiles
4.1 General overview
EtherCAT® is a Real-Time Ethernet technology based on ISO/IEC/IEEE 8802-3, IEC 61158-2,
IEC 61158-3-12, IEC 61158-4-12, IEC 61158-5-12 and IEC 61158-6-12 especially suitable for
communication between control systems and peripheral devices like I/O systems, drives,
sensors and actuators.
In this document, the following communication profiles are specified for CPF 12:
– Profile 12/1
This profile defines protocol and service selections for simple I/O devices which can
communicate process data cyclically.
– Profile 12/2
This profile defines protocol and service selections for two types of devices:
• smart or modular devices with mailbox communication capabilities;
• such devices that additionally support time based synchronization for performing tightly
coordinated actions.
All three types of devices can be mixed arbitrarily.
4.2 CP 12/1
4.2.1 Physical layer
The physical layer is described in IEC 61158-2 and ISO/IEC/IEEE 8802-3:2021. Table 2
specifies the use of the physical layer, specified in ISO/IEC/IEEE 8802-3:2021, included in this
profile.
Table 3 specifies the use of a power integrated physical layer, specified in IEC 61158-2,
included in this profile.
Table 2 – CP 12/1: PhL selection of physical layer
from ISO/IEC/IEEE 8802-3:2021
Clause Header Presence Constraints
1 Introduction YES —
2 Media Access Control (MAC) service YES —
specification
3 Media Access Control (MAC) frame and YES —
packet specifications
4 Media Access Control NO —
5 Layer Management Optional —
6…20 -- NO —
Annex 4A Simplified full duplex media access YES —
control
21 Introduction to 100 Mb/s baseband YES —
networks, type 100BASE-T
___________
EtherCAT® is a registered trade name of Beckhoff, Verl. This information is given for the convenience of users
of this document and does not constitute an endorsement by the IEC of the trademark holder or any of its
products. Compliance with this profile does not require use of the trade name EtherCAT. Use of the trade name
EtherCAT requires permission from the trade name holder.

– 10 – IEC 61784-2-12:2023 © IEC 2023
Clause Header Presence Constraints
22 Reconciliation Sublayer (RS) and Media YES —
Independent Interface (MII)
23 Physical Coding Sublayer (PCS), Physical NO —
Medium Attachment (PMA) sublayer and
baseband medium, type 100BASE-T4
24 Physical Coding Sublayer (PCS) and YES —
Physical Medium Attachment (PMA)
sublayer, type 100BASE-X
Physical Medium Dependent (PMD)
25 Optional Preferred technology
sublayer and baseband medium, type
100BASE-TX
Physical Medium Dependent (PMD) Use for specific environmental
26 Optional
sublayer and baseband medium, type conditions
100BASE-FX
27 Repeater for 100 Mb/s baseband NO
networks
28 Physical Layer link signaling for Auto- Optional Auto-negotiation and auto-crossover
Negotiation on twisted pair are highly recommended
29 System considerations for multisegment NO —
100BASE-T networks
30 … 32 -- NO —
33 Data Terminal Equipment (DTE) Power Optional —
via Media Dependent Interface (MDI)
Annex 22A…D MII YES —
Annex 23A…C 6T codewords NO —
Annex 27A Repeater delay consistency requirements NO —
Annex 28A…D Selector Field definitions YES
Annex 29A…B DTE and repeater delay components Optional —
Annex 30A…C G
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