IEC 61784-1-4:2023

IEC 61784-1-4 ®
Edition 1.0 2023-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Industrial networks – Profiles –
Part 1-4: Fieldbus profiles – Communication Profile Family 4

Réseaux industriels – Profils –
Partie 1-4: Profils de bus de terrain – Famille de profils de communication 4

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IEC 61784-1-4 ®
Edition 1.0 2023-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Industrial networks – Profiles –

Part 1-4: Fieldbus profiles – Communication Profile Family 4

Réseaux industriels – Profils –

Partie 1-4: Profils de bus de terrain – Famille de profils de communication 4

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 35.100.20; 35.240.50 ISBN 978-2-8322-6588-8

– 2 – IEC 61784-1-4:2023 © IEC 2023
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Terms, definitions, abbreviated terms, symbols, and conventions . 7
3.1 Terms and definitions. 7
3.2 Abbreviations and symbols . 7
3.2.1 Common abbreviations and symbols . 7
3.2.2 Other abbreviations and symbols . 7
3.3 Conventions . 7
4 CPF 4 (P-NET®) . 7
4.1 General overview . 7
4.2 CP 4/1 (P-NET RS-485) . 8
4.2.1 Physical layer . 8
4.2.2 Data-link layer . 9
4.2.3 Application layer . 10
Annex A (informative) CPF 4 (P-NET) communication concepts . 12
Bibliography . 14

Table 1 – CP 4/1: PhL selection . 9
Table 2 – CP 4/1: DLL service selection . 10
Table 3 – CP 4/1: DLL protocol selection . 10
Table 4 – CP 4/1: AL service selection . 11
Table 5 – CP 4/1: AL protocol selection . 11

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
INDUSTRIAL NETWORKS –
PROFILES –
Part 1-4: Fieldbus profiles –
Communication Profile Family 4

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
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preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with
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3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
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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
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expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
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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.
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 61784-1-4 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 fifth
edition of IEC 61784-1 published in 2019. This first edition constitutes a technical revision.

– 4 – IEC 61784-1-4:2023 © IEC 2023
This edition includes the following significant technical changes with respect to
IEC 61784-1:2019:
a) split of the original IEC 61784-1 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/1207/FDIS 65C/1236/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 61784-1 series, published under the general title Industrial networks
– Profiles – Part 1: Fieldbus profiles, 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.
INTRODUCTION
The IEC 61784-1 series provides a set of Communication Profiles (CP) in the sense of
ISO/IEC TR 10000-1. These answer the need of identifying the protocol families co-existing
within the IEC 61158 series, as a result of the international harmonization of fieldbus
technologies available on the market. More specifically, these profiles help to correctly state
the compliance with the IEC 61158 series, and to avoid the spreading of divergent
implementations, which would limit its use, clearness and understanding. Additional profiles to
address specific market concerns, such as functional safety or information security, can be
addressed by future parts of the IEC 61784-1 series.
The IEC 61784-1 series contains several Communication Profile Families (CPF), which specify
one or more communication profiles. Such profiles identify, in a strict sense, protocol subsets
of the IEC 61158 series via protocol specific communication profiles. They do not define device
profiles that specify communication profiles together with application functions needed to
answer the need of a specific application ("application profiles").
It is agreed that these latter classes of profiles would facilitate the use of the IEC 61158 series
of standards; the profiles defined in the IEC 61784-1 series are a necessary step to achieve
that task.
It is also important to clarify that interoperability – defined as the ability of two or more network
systems to exchange information and to make mutual use of the information that has been
exchanged (see ISO/IEC TR 10000-1) – can be directly achieved on the same link only for those
devices complying with the same communication profile.
Profiles contained in the IEC 61784-1 series are constructed of references to IEC 61158-2 and
the IEC 61158-3, IEC 61158-4, IEC 61158-5 and IEC 61158-6 series, and other IS, TS or
worldwide-accepted standards, as appropriate . Each profile is required to reference at least
one part of the IEC 61158 series in addition to IEC 61158-1.
Two or more Profiles, which are related to a common family, are specified within a
"Communication Profile Family" (CPF).

___________
International Standardised Profiles may contain normative references to specifications other than International
Standards; see ISO/IEC JTC 1 N 4047: The Normative Referencing of Specifications other than International
Standards in JTC 1 International Standardized Profiles – Guidelines for ISP Submitters.

– 6 – IEC 61784-1-4:2023 © IEC 2023
INDUSTRIAL NETWORKS –
PROFILES –
Part 1-4: Fieldbus profiles –
Communication Profile Family 4

1 Scope
This part of IEC 61784-1 defines Communication Profile Family 4 (CPF 4). CPF 4 specifies a
set of protocol specific communication profiles (CPs) based on the IEC 61158 series (Type 4)
and other standards, to be used in the design of devices involved in communications in factory
manufacturing and process control.
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 Some CPs of CPF 4 are specified in IEC 61784-2-4.
Each CP selects an appropriate consistent and compatible subset of services and protocols
from the relevant set that is defined and modelled in the IEC 61158 series. For the selected
subset of services and protocols, the profile also describes any possible or necessary
constraints in parameter values.
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 61158-3-4:2023, Industrial communication networks – Fieldbus specifications – Part 3-4:
Data-link layer service definition – Type 4 elements
IEC 61158-4-4:2023, Industrial communication networks – Fieldbus specifications – Part 4-4:
Data-link layer protocol specification – Type 4 elements
IEC 61158-5-4:2023, Industrial communication networks – Fieldbus specifications – Part 5-4:
Application layer service definition – Type 4 elements
IEC 61158-6-4:2023, Industrial communication networks – Fieldbus specifications – Part 6-4:
Application layer protocol specification – Type 4 elements
IEC 61784-1-0:2023, Industrial networks – Profiles – Part 1-0: Fieldbus profiles – General
concepts and terminology
IEC 61784-2-4:2023, Industrial networks – Profiles – Part 2-4: Additional real-time fieldbus
profiles based on ISO/IEC/IEEE 8802-3 – CPF 4
ISO/IEC/IEEE 8802-3, Telecommunications and exchange between information technology
systems – Requirements for local and metropolitan area networks – Part 3: Standard for
Ethernet
TIA-485-A:1998, Electrical Characteristics of Generators and Receivers for Use in Balanced
Digital Multipoint Systems
3 Terms, definitions, abbreviated terms, symbols, and conventions
3.1 Terms and definitions
For the purposes of this document, all terms and definitions provided in the IEC 61158 series
and IEC 61784-1-0 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 Abbreviations and symbols
3.2.1 Common abbreviations and symbols
For the purposes of this document, all abbreviations and symbols defined in the IEC 61158
series and IEC 61784-1-0 apply.
CP communication profile
CPF communication profile family
MAU medium attachment unit
3.2.2 Other abbreviations and symbols
IP internet protocol (see IETF RFC 791)
RS 485 MAU according to TIA-485-A
UDP user datagram protocol (see IETF RFC 768)
3.3 Conventions
For the purposes of this document, the conventions defined in IEC 61784-1-0 apply.
4 CPF 4 (P-NET® )
4.1 General overview
Communication Profile Family 4 defines profiles based on IEC 61158-2 type 4, IEC 61158-3-4,
IEC 61158-4-4, IEC 61158-5-4 and IEC 61158-6-4, which corresponds to parts of a
communication system commonly known as P-NET.
___________
P-NET is the trade name of International P-NET User Organisation ApS (IPUO). This information is given for the
convenience of users of this document and does not constitute an endorsement by IEC of the trademark holder
or any of its products. Compliance with this profile does not require use of the trade name P-NET. Use of the
trade name P-NET requires permission of the trade name holder.

– 8 – IEC 61784-1-4:2023 © IEC 2023
CPF 4 (P-NET) communication concepts are explained in Annex A.
Profile 4/1 P-NET RS-485
This profile contains AL, DLL and PhL services and protocol references with an
IEC 61158 compliant application access. Profile 4/1 is based on TIA-485-A, and allows
up to 125 devices of normal or simple class to communicate on the same physical link,
in half duplex mode.
Profile 4/2 Void
Profile 4/3 P-NET on IP
This profile contains AL and DLL services and protocol references with an IEC 61158
compliant application access. Profile 4/3 is based to ISO/IEC/IEEE 8802-3, and allows
up to 125 devices of normal class to communicate on the same logical link, in full duplex
mode.
Profile 4/1 is described in this document, whereas profile 4/3 is described in IEC 61784-2-4.
4.2 CP 4/1 (P-NET RS-485)
4.2.1 Physical layer
Table 1 holds the physical layer service and protocol selections from IEC 61158-2 for this
profile.
Table 1 – CP 4/1: PhL selection
Clause Header Presence Constraints
1 Scope YES —
2 Normative references Partial Used if needed
3 Terms and definitions Partial Used when applicable
4 Symbols and abbreviated terms Partial Used when applicable
5 Data-link layer – Physical Layer Interface — —
5.1 General YES —
5.2 – 5.4 — NO —
5.5 Type 4: Required services YES See text following this table
Next — NO —
subclauses
6 Station Management – Physical Layer — —
Interface
6.1 General YES —
6.2 Type 1: Station Management – Physical Layer Partial Only Ph-SETVALUE and
interface Ph-GETVALUE
6.3 — NO —
6.4 Type 4: Station Management – Physical Layer YES At least, Baud rate 76800 shall
interface be supported. Only half duplex
mode shall be supported
Next — NO —
subclauses
7 – 8 — NO —
9 Medium Dependent Sublayer (MDS) — —
9.1 General YES —
9.2 – 9.5 — NO —
9.6 Type 4: MDS: Wire medium — —
9.6.1 Half Duplex YES —
9.6.2 Full Duplex NO —
Next — NO —
subclauses
10 – 23 — NO —
24 Type 4: Medium Attachment Unit: RS-485 YES —
Next clauses — NO —
Next annexes — NO —
Simple class devices shall only support:
a) Ph-Data request, classes start-of-activity-11, data and end-of-activity.
b) Ph-DATA indication, classes START-OF-ACTIVITY and DATA.
4.2.2 Data-link layer
4.2.2.1 DLL service selection
Table 2 holds the Data-link layer service selections from IEC 61158-3-4 for this profile.

– 10 – IEC 61784-1-4:2023 © IEC 2023
Table 2 – CP 4/1: DLL service selection
Clause Header Presence Constraints
1 Scope YES —
2 Normative references Partial Used if needed
3 Terms, definitions, symbols, Partial Used when applicable
abbreviated terms and conventions
4 Data-link Service and concepts YES —
5 DL-management Service — —
5.1 Scope and inheritance NO —
5.2 Facilities of the DL-management Partial Items a) and b)
service
5.3 Model of the DL_management service YES —
5.4 Constraints on sequence of primitives Partial Only the parts referring to DLM-SET and
DLM-GET
5.5 SET YES —
5.6 GET YES —
5.7 – 5.8 — NO —
For this profile, DLS-user data size is limited to 56 octets and hence the Data-field-format
parameter always holds one octet of information, as described in IEC 61158-3-4, 4.7.2.11.
4.2.2.2 DLL protocol selection
Table 3 holds the Data-link layer protocol selections from IEC 61158-4-4 for this profile.
Table 3 – CP 4/1: DLL protocol selection
Clause Header Presence Constraints
1 Scope YES —
2 Normative references Partial Used if needed
3 Definitions, symbols and abbreviated Partial Used when applicable
terms
a
4 Data-link Protocol definition YES
a
A device shall provide at least the necessary protocol options to fulfill the supported services.

For this profile, only half duplex transmission, as defined in IEC 61158-4-4, 4.1.3.3 should be
supported.
Simple class devices should support responder functionality only, as defined in IEC 61158-4-4,
4.1.2.
For this profile, the Data-field-format field always holds one octet of information, and shall be
interpreted as described in IEC 61158-4-4, 4.2.3.4.
4.2.3 Application layer
4.2.3.1 AL service selection
Table 4 holds the application layer service selections from IEC 61158-5-4 for this profile.

Table 4 – CP 4/1: AL service selection
Clause Header Presence Constraints
Whole Application layer service definition – Type 4 YES Used up to the exceptions
document elements below
5.3.2.1 Application relationship formal model YES At least, baud rate 76 800
shall be supported
Simple class devices shall only support Real Variable Objects, defined in IEC 61158-5-4,
5.2.5.3 (not Proxy Variable Objects) and only the objects needed for the variable types, which
are actually present in the device.
Normal class devices shall support the Real Variable Objects needed for the variable types,
which are actually present in the device, and Proxy Variable Objects for all of the variable types
listed in IEC 61158-5-4, 5.2.
Simple class devices shall not support the RESPONSE Service, defined in IEC 61158-5-4,
5.2.6.2.
4.2.3.2 AL protocol selection
Table 5 holds the application layer protocol selections from IEC 61158-6-4 for this profile.
Table 5 – CP 4/1: AL protocol selection
Clause Header Presence Constraints
a
Whole Application layer protocol specification – Type 4 YES

document elements
a
A device shall provide at least the necessary protocol options to fulfill the supported services. If the Service
Write with SecureDataExchange is required in a device, the Service Method shall also be provided in order to
perform the exchange of Nonce’es for creating and validating Signatures.

For this profile, the value of "addressed AREP attribute MaxDataSize", which is defined in APDU
header of IEC 61158-6-4, Table 2 is limited to 56 octets.

– 12 – IEC 61784-1-4:2023 © IEC 2023
Annex A
(informative)
CPF 4 (P-NET) communication concepts
The P-NET Fieldbus is designed to connect distributed process components like process
computers, intelligent sensors, actuators, I/O modules, field and central programmable
controllers, etc., via a common two wire cable. Beyond being used for transmitting process data,
P-NET is also used for data collection, for configuration of nodes/sensors, and for downloading
of programs.
The typical P-NET application requires response times measured in ms, and a bus length up to
one km or more. There are other types of applications which demand a response time measured
in μs. For these applications, P-NET is not appropriate. P-NET applications are found in the
process industry environment and in discrete parts manufacturing plants. P-NET is as well
suited for small plants, as for large plants having many controllers, sensors, and interface
modules. In addition, any such system is always ready for any necessary expansion.
P-NET can handle up to 300 confirmed data transactions per second, from 300 independent
addresses. Data can be transferred in the form of fully processed values (floating point), such
as temperature, pressure etc., or as for example blocks of 32 independent binary signals,
indicating valve states, switch positions, etc. This results in a performance of up to 9,600 binary
signals per second being accessed from anywhere within the complete system.
The result of a measurement made by a responder is presented to an initiator in a pre-processed
form, for example in SI (metric) engineering units. This means that no repetitive scaling or
conversion needs to be done by the initiator(s).
The physical layer of P-NET can be based on the RS-485 standard using a shielded twisted
pair cable. This allows a cable length of up to 1 200 m without repeaters. P-NET devices are
galvanically isolated, and up to 125 devices per link can be connected. P-NET is a multi-master
bus, which can accept up to 32 initiators per link. All communication is based on the principle
where an Initiator sends a request, and the addressed Responder returns an immediate
response.
The right to access the link is transferred from one P-NET initiator to another, by means of a
token. P-NET uses a method called "virtual token passing", which does not require messages
to be sent over the link.
P-NET allows direct addressing between several links, also known as a multi-link structure.
This feature is a specified part of the P-NET protocol, and it can be built into the standard
operating system of multi-port initiators. Communication is directed through the different links
via devices with two or more P-NET ports. This means that any initiator on one link can
transparently access any device within any other link, without the need for special programming
in the multi-port devices. The benefits gained by dividing a system into smaller sections are
highly significant, because it limits the consequences of an error to a single link, which gives
higher system security. Furthermore, the multi-link structure provides a natural redundancy.
There is no hierarchical structuring of the links. This is of great benefit when expanding existing
P-NET installations, and when coupling to other networks.
Any P-NET device, including an initiator, can be powered down or connected to or disconnected
from the link, without interfering with the rest of the system. Consequently, devices can be
exchanged during system operation, and a system can be expanded while the remaining
production system continues to run.
Implementation of the P-NET protocol requires very little program space. Typically, a simple
class device P-NET implementation requires approximately 4 Kbytes of program space when
written in "C".
Programmable P-NET modules that include an Ethernet port have been made available, where
the in-built operating system provides transparent P-NET communication between two points
connected locally or via the Internet. Standardized Ethernet wiring and connectors also provide
the means of interconnection of switches, to avoid media access collisions, and wireless access
points and routers (WLAN), as a highly convenient media alternative. When connecting two or
more industrial networks together using this method, it will, more often than not, contain real-
time measurement or process data. This technology is therefore now referred to as Real Time
Ethernet (RTE). In essence, the P-NET protocol and message structure has not been changed.
What happens, is that the familiar message structure used, say via RS 485, is 'wrapped' in a
'user datagram' using the transport protocol within IP called UDP. Using this technology, it is
necessary to define specific usage ports as a means of defining the underlying message
protocol (i.e. P-NET). The P-NET on IP extensions to the current P-NET standard includes a
description of the structure of UDP/IP packages for P-NET messages. These enhance current
definitions of P-NET message addressing modes (e.g. simple, extended, complex) with IP,
including associated routing definitions. Implementation of P-NET on IP for Real Time Ethernet
means that P-NET packages can be routed through IP networks in exactly the same way as
they can be routed through non-IP networks. Routing can be through any type of P-NET network
and in any order. Nodes on an IP network are addressed with two P-NET Route elements, but
this is entirely handled by the IP nodes. This means that any P-NET client (master) can access
servers on an IP network, without knowing anything about IP addresses.

– 14 – IEC 61784-1-4:2023 © IEC 2023
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IEC 60793 (all parts), Optical fibres
IEC 60807-3, Rectangular connectors for frequencies below 3 MHz – Part 3: Detail specification
for a range of connectors with trapezoidal shaped metal shells and round contacts – Removable
crimp contact types with closed crimp barrels, rear insertion/rear extraction
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and guidance for the IEC 61158 and IEC 61784 series
IEC 61158-3 (all parts), Industrial communication networks – Fieldbus specifications – Part 3:
Data-link layer service definition
IEC 61158-4 (all parts), Industrial communication networks – Fieldbus specifications – Part 4:
Data-link layer protocol specification
IEC 61158-5 (all parts), Industrial communication networks – Fieldbus specifications – Part 5:
Application layer service definition
IEC 61158-6 (all parts), Industrial communication networks – Fieldbus specifications – Part 6:
Application layer protocol specification
IEC 61784-1 (all parts), Industrial networks – Profiles – Part 1: Fieldbus profiles
IEC 61784-2 (all parts), Industrial networks – Profiles – Part 2: Additional real-time fieldbus
profiles based on ISO/IEC/IEEE 8802-3
ISO/IEC 2022, Information technology – Character code structure and extension techniques
ISO/IEC 7498-1, Information technology – Open Systems Interconnection – Basic Reference
Model: The Basic Model
ISO/IEC TR 10000-1, Information technology – Framework and taxonomy of International
Standardized Profiles – Part 1: General principles and documentation framework
ISO/IEC 10731, Information technology – Open Systems Interconnection – Basic Reference
Model – Conventions for the definition of OSI services
ISO/IEC 7498-3, Information technology – Open Systems Interconnection – Basic Reference
Model: Naming and addressing
IETF RFC 768, J. Postel, User Datagram Protocol, August 1980, available at https://www.rfc-
editor.org/info/rfc768 [viewed 2022-02-18]
IETF RFC 791, J. Postel, Internet Protocol, September 1981, available at https://www.rfc-
editor.org/info/rfc791 [viewed 2022-02-18]

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– 16 – IEC 61784-1-4:2023 © IEC 2023
SOMMAIRE
AVANT-PROPOS . 17
INTRODUCTION . 19
1 Domaine d’application . 20
2 Références normatives . 20
3 Termes, définitions, abréviations, symboles et conventions . 21
3.1 Termes et définitions . 21
3.2 Abréviations et symboles . 21
3.2.1 Abréviations et symboles communs . 21
3.2.2 Autres abréviations et symboles . 21
3.3 Conventions . 21
4 CPF 4 (P-NET®) . 22
4.1 Présentation générale . 22
4.2 CP 4/1 (P-NET RS 485) . 22
4.2.1 Couche physique . 22
4.2.2 Couche liaison de données . 24
4.2.3 Couche application . 25
Annexe A (informative) Concepts de communication de la CPF 4 (P-NET) . 26
Bibliographie . 28

Tableau 1 – CP 4/1: sélection de la PhL . 23
Tableau 2 – CP 4/1: sélection des services DLL . 24
Tableau 3 – CP 4/1: sélection du protocole DLL . 24
Tableau 4 – CP 4/1: sélection des services AL. 25
Tableau 5 – CP 4/1: sélection du protocole AL . 25

COMMISSION ÉLECTROTECHNIQUE INTERNATIONALE
____________
RÉSEAUX INDUSTRIELS –
PROFILS –
Partie 1-4: Profils de bus de terrain –
Famille de profils de communication 4

AVANT-PROPOS
1) La Commission Électrotechnique Internationale (IEC) est une organisation mondiale de normalisation
composée de l’ensemble des comités électrotechniques nationaux (Comités nationaux de l’IEC). L’IEC a pour
objet de favoriser la coopération internationale pour toutes les questions de normalisation dans les domaines
de l’électricité et de l’électronique. A cet effet, l’IEC – entre autres activités – publie des Normes
internationales, des Spécifications techniques, des Rapports techniques, des Spécifications accessibles au
public (PAS) et des Guides (ci-après dénommés "Publication(s) de l’IEC"). Leur élaboration est confiée à des
comités d’études, aux travaux desquels tout Comité national intéressé par le sujet traité peut participer. Les
organisations internationales, gouvernementales et non gouvernementales, en liaison avec l’IEC, participent
également aux travaux. L’IEC collabore étroitement avec l’Organisation Internationale de Normalisation (ISO),
selon des conditions fixées par accord entre les deux organisations.
2) Les décisions ou accords officiels de l’IEC concernant les questions techniques représentent, dans la mesure
du possible, un accord international sur les sujets étudiés, étant donné que les Comités nationaux de l’IEC
intéressés sont représentés dans chaque comité d’études.
3) Les Publications de l’IEC se présentent sous la forme de recommandations internationales et sont agréées
comme telles par les Comités nationaux de l’IEC. Tous les efforts raisonnables sont entrepris afin que l’IEC
s’assure de l’exactitude du contenu technique de ses Publications; l’IEC ne peut pas être tenue responsable de
l’éventuelle mauvaise utilisation ou interprétation qui en est faite par un quelconque utilisateur final.
4) Dans le but d’encourager l’uniformité internationale, les Comités nationaux de l’IEC s’engagent, dans toute la
mesure possible, à appliquer de façon transparente les Publications de l’IEC dans leurs publications nationales
et régionales. Toutes divergences entre toutes Publications de l’IEC et toutes publications nationales ou
régionales correspondantes doivent être indiquées en termes clairs dans ces dernières.
5) L’IEC elle-même ne fournit aucune attestation de conformité. Des organismes de certification indépendants
fournissent des services d’évaluation de conformité et, dans certains secteurs, accèdent aux marques de
conformité de l’IEC. L’IEC n’est responsable d’aucun des services effectués par les organismes de certification
indépendants.
6) Tous les utilisateurs doivent s’assurer qu’ils sont en possession de la dernière édition de cette publication.
7) Aucune responsabilité ne doit être imputée à l’IEC, à ses administrateurs, employés, auxiliaires ou
mandataires, y compris ses experts particuliers et les membres de ses comités d’études et des Comités
nationaux de l’IEC, pour tout préjudice causé en cas de dommages corporels et matériels, ou de tout autre
dommage de quelque nature que ce soit, directe ou indirecte, ou pour supporter les coûts (y compris les frais
de justice) et les dépenses découlant de la publication ou de l’utilisation de cette Publication de l’IEC ou de
toute autre Publication de l’IEC, ou au crédit qui lui est accordé.
8) L’attention est attirée sur les références normatives citées dans cette publication. L’utilisation de publications
référencées est obligatoire pour une application correcte de la présente publication.
9) L’attention est attirée sur le fait que certains des éléments de la présente Publication de l’IEC peuvent faire
l’objet de droits de brevet. L’IEC ne saurait être tenue pour responsable de ne pas avoir identifié de tels droits
de propriété et averti de leur existence.
L’attention est attirée sur le fait que l’utilisation de certains des types de protocoles associés
est restreinte par les détenteurs des droits de propriété intellectuelle. En tout état de cause,
l’engagement de renonciation partielle aux droits de propriété intellectuelle pris par les
détenteurs de ces droits autorise l’utilisation d’un type de protocole de couche avec les autres
protocoles de couche du même type, ou dans des combinaisons avec d’autres types
autorisées explicitement par les détenteurs respectifs des droits de propriété intellectuelle
pour ces types.
NOTE Les combinaisons de types de protocoles sont spécifiées dans la série IEC 61784-1 et dans la série
IEC 61784-2.
– 18 – IEC 61784-1-4:2023 © IEC 2023
L’IEC 61784-1-4 a été établie par le sous-comité 65C: Réseaux industriels, du comité
d’études 65 de l’IEC: Mesure, commande et automation dans les processus industriels Il
s’agit d’une Norme internationale.
Cette première édition, conjointement avec les autres parties de la même série, annule et
remplace la cinquième édition de l’IEC 61784-1 parue en 2019. Cette première édition
constitue une révision technique.
Cette édition inclut les modifications techniques majeures suivantes par rapport à
l’IEC 61784-1:2019:
a) scission de l’IEC 61784-1 d’origine en plusieurs sous-parties, une sous-partie pour le
matériel de nature gé
...