IEC 62424:2016

Representation of process control engineering - Requests in P&I diagrams and data exchange between P&ID tools and PCE-CAE tools

IEC 62424:2016 specifies how process control engineering requests are represented in a P&ID for automatic transferring data between P&ID and PCE tool and to avoid misinterpretation of graphical P&ID symbols for PCE. It also defines the exchange of process control engineering request relevant data between a process control engineering tool and a P&ID tool by means of a data transfer language (called CAEX). These provisions apply to the export/import applications of such tools. This second edition cancels and replaces the first edition published in 2008. This edition constitutes a technical revision. It is a compatible extension of the first edition. The main changes and extensions are:
- updated definitions and new definitions;
- identification replaced with reference designation;
- updated PCE categories and process functions;
- CAEX version 3.0, introduction of: native multiple role support;
- nested interfaces;
- life cycle meta information;
- a separate Attribute library;
- updated examples;
- updated electronic data model of the PCE request: new normative attribute library for basic PCE request attributes;
- new informative extended attribute library for further PCE request attributes;
- new informative electronic data model for the PCE request.

Représentation de l'ingénierie de commande de processus - Demandes sous forme de diagrammes P&I et échange de données entre outils P&ID et outils PCE-CAE

L'IEC 62424:2016 spécifie la méthode de représentation des demandes d'ingénierie de commande de processus dans un diagramme P&I en vue d'un transfert automatique de données entre les outils P&ID et PCE, et de manière à prévenir toute interprétation erronée des symboles P&ID graphiques pour une application PCE. Elle définit également l'échange de données de type demandes d'ingénierie de commande de processus entre un outil d'ingénierie de commande de processus et un outil P&ID au moyen d'un langage de transfert de données (appelé CAEX). Ces dispositions s'appliquent aux fonctions exportation/importation de ces outils. Cette deuxième édition annule et remplace la première édition parue en 2008. Cette édition constitue une révision technique. Elle est une extension compatible de la première édition. Les principales modifications et extensions sont décrites à l'Annexe E et résumées ci-dessous:
- mise à jour et ajout de définitions;
- remplacement du terme "identification" par "désignation de référence";
- mise à jour des catégories PCE et des fonctions de traitement;
- version CAEX 3.0, introduisant les éléments suivants: rôles multiples natifs;
- interfaces imbriquées;
- informations supplémentaires sur le cycle de vie;
- bibliothèque Attribute séparée;
- exemples mis à jour;
- mise à jour du modèle de données électroniques de la demande PCE: nouvelle bibliothèque d'attributs normative pour les attributs de demande PCE de base;
- nouvelle bibliothèque d'attributs étendue informative pour les autres attributs de demande PCE;
- nouveau modèle de données électroniques informatif de la demande PCE.

General Information

• Status: Published
• Publication Date: 14-Jul-2016
• ICS: 25.040.40 - Industrial process measurement and control
• ICS: 35.240.50 - IT applications in industry
• Technical Committee: TC 65 - Industrial-process measurement, control and automation
• Drafting Committee: WG 12 - TC 65/WG 12
• Current Stage: PPUB - Publication issued
• Start Date: 15-Jul-2016
• Completion Date: 15-Jul-2016

Relations

• Revises: IEC 62424:2008 - Representation of process control engineering - Requests in P&I diagrams and data exchange between P&ID tools and PCE-CAE tools
• Effective Date: 05-Sep-2023

Overview

IEC 62424:2016 is an international standard published by the International Electrotechnical Commission (IEC) that defines the representation and exchange of process control engineering (PCE) requests within Piping and Instrumentation Diagrams (P&IDs). It facilitates seamless data interoperability between P&ID tools and process control engineering computer-aided engineering (PCE-CAE) tools to ensure accurate automatic data transfer. This prevents misinterpretation of graphical symbols and supports high-integrity process control design.

The 2016 edition is a technical revision and compatible extension of the original 2008 version. It introduces updated definitions, enhanced PCE categories and process functions, and adopts CAEX version 3.0 for data exchange including native multiple role support and nested interfaces. Additionally, it provides a comprehensive attribute library for PCE requests, further improving data consistency and lifecycle management.

Key Topics

• Representation of PCE Requests in P&IDs:
  Clear guidelines on how to depict process control requests and loops graphically, including reference designation systems and operator interface locations. Supports consistent interpretation of PCE categories, control functions, alarm and switching functions, and quality or safety-relevant elements.

• Data Exchange via CAEX Format:
  The standard defines the neutral data exchange language CAEX (Computer Aided Engineering Exchange) for transferring PCE relevant data between P&ID and PCE-CAE tools. CAEX version 3.0 introduces enhanced features such as native multiple role support, nested interfaces, and meta-information to support plant lifecycle data management.

• Standardized Attribute Libraries:
  IEC 62424 provides normative and informative attribute libraries for PCE request properties, enabling uniform data descriptions and easier tool integration.

• Conformity and Compliance:
  The document outlines requirements to ensure that automated import/export processes between P&ID tools and process control engineering applications maintain data integrity and semantic accuracy.

• Updated Definitions and Models:
  Revised terminology and updated electronic data models ensure alignment with current process control engineering practices.

Applications

IEC 62424:2016 is essential for industries relying on complex process control systems, including:

• Chemical and Petrochemical Plants:
  For precise control system design, ensuring P&IDs accurately reflect control requests and integrate effectively with engineering software.

• Pharmaceutical Manufacturing:
  Where safety, GMP (Good Manufacturing Practice), and quality-relevant PCE requests must be carefully represented and exchanged to meet regulatory standards.

• Power Generation and Utilities:
  To help in accurate representation of control functions and facilitate automated engineering workflows.

• Process Automation Engineering:
  Supports software tool vendors and system integrators in harmonizing data exchange protocols between design and control engineering tools, streamlining project execution.

• Lifecycle Management of Control Systems:
  By incorporating lifecycle meta information, IEC 62424 enables better planning, updates, and maintenance of control engineering processes.

Related Standards

• IEC 61131 (Programmable Controllers): Standards defining programming languages and interfaces in industrial automation.

• ISA-5.1 (Instrument Identification and Tagging): Provides conventions on instrumentation symbols and tagging that complement IEC 62424 P&ID representations.

• ISO 15926 (Industrial Automation Systems and Integration): Facilitates integration of complex plant engineering data, covering interoperability beyond control engineering.

• IEC 61511 (Functional Safety - Safety Instrumented Systems): Related to design and validation of safety control loops represented in P&IDs per IEC 62424.

• IEC 81346 (Structuring Principles and Reference Designations): Supports consistent reference designation systems as adopted and extended in IEC 62424.

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Keywords: IEC 62424, process control engineering, P&ID, process automation, CAEX data exchange, PCE requests, plant engineering data, process control symbols, control loop representation, lifecycle meta information, PCE-CAE tools, process instrumentation diagrams, industrial automation standards, safety and quality control, data interoperability.

Standards Content (Sample)

IEC 62424 ®
Edition 2.0 2016-07
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Representation of process control engineering – Requests in P&I diagrams and
data exchange between P&ID tools and PCE-CAE tools

Représentation de l'ingénierie de commande de processus – Demandes sous
forme de diagrammes P&I et échange de données entre outils P&ID et outils
PCE-CAE
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IEC 62424 ®
Edition 2.0 2016-07
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Representation of process control engineering – Requests in P&I diagrams and

data exchange between P&ID tools and PCE-CAE tools

Représentation de l'ingénierie de commande de processus – Demandes sous

forme de diagrammes P&I et échange de données entre outils P&ID et outils

PCE-CAE
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 25.040.40; 35.240.50 ISBN 978-2-8322-3477-8

– 2 – IEC 62424:2016  IEC 2016
CONTENTS
FOREWORD . 8
INTRODUCTION . 10
1 Scope . 12
2 Normative references. 12
3 Terms and definitions . 12
4 Abbreviations . 17
5 Conformity . 18
6 Representation of PCE requests in a P&ID . 19
6.1 PCE request and PCE loop . 19
6.2 Objectives and principles . 20
6.3 Requirements for the reference designation and representation of PCE
requests . 20
6.3.1 General . 20
6.3.2 Types of lines . 21
6.3.3 Displaying the location of the operator interface . 21
6.3.4 PCE categories and processing functions . 22
6.3.5 PCE request reference designation system . 25
6.3.6 PU-vendor and typical identification . 26
6.3.7 Device information . 26
6.3.8 Alarming, switching and indicating . 27
6.3.9 Safety-relevant, GMP and quality-relevant PCE requests . 27
6.3.10 PCE control functions . 28
7 Neutral data exchange of PCE relevant P&ID information . 29
7.1 Objectives . 29
7.2 Meaning of P&ID elements . 29
7.3 PCE relevant information of P&ID tools . 30
7.4 Formal description of PCE relevant information of P&ID tools . 31
7.4.1 General object model of a plant hierarchy . 31
7.4.2 General object model of a PCE request . 31
7.5 Modeling PCE relevant information using the CAEX system description
language . 32
7.5.1 Overview . 32
7.5.2 Basic CAEX mappings . 33
7.5.3 Standard CAEX library of PCE request related attributes . 34
7.5.4 Mapping of indirect links between PCE requests of different plant
sections . 35
7.5.5 CAEX description of direct links between PCE requests of different
plant sections. 38
7.5.6 PCE loops. 40
8 Additional PCE attributes . 40
Annex A (normative) CAEX – Data model for machine information exchange . 42
A.1 CAEX and its diagram conventions . 42
A.2 General CAEX concepts . 43
A.2.1 General CAEX terms . 43
A.2.2 General CAEX concept description . 46
A.2.3 Data definition of SystemUnitClass . 50

A.2.4 Definition of attributes . 52
A.2.5 Data definition of an AttributeType . 54
A.2.6 Data definition of InterfaceClass . 56
A.2.7 Data definition of RoleClass . 59
A.2.8 Modelling of relations . 60
A.2.9 Usage of paths . 68
A.2.10 CAEX role concept . 69
A.2.11 Use of the CAEX MappingObject . 74
A.2.12 References to external CAEX files . 76
A.3 CAEX schema definition . 78
A.3.1 General . 78
A.3.2 Element CAEXFile . 79
A.3.3 CAEXFile/SuperiorStandardVersion . 81
A.3.4 CAEXFile/ SourceDocumentInformation . 81
A.3.5 CAEXFile/ExternalReference . 82
A.3.6 CAEXFile/InstanceHierarchy . 83
A.3.7 CAEXFile/InstanceHierarchy/InternalElement . 84
A.3.8 CAEXFile/InterfaceClassLib . 85
A.3.9 CAEXFile/InterfaceClass . 86
A.3.10 CAEXFile/RoleClassLib . 87
A.3.11 CAEXFile/RoleClass . 88
A.3.12 CAEXFile/SystemUnitClassLib . 89
A.3.13 CAEXFile/SystemUnitClass . 90
A.3.14 CAEXFile/AttributeTypeLib . 91
A.3.15 Group Header . 93
A.3.16 CAEX complex type AttributeFamilyType . 98
A.3.17 CAEX complex type AttributeFamilyType/AttributeType . 99
A.3.18 CAEX complex type AttributeType . 100
A.3.19 CAEX complex type CAEXBasicObject . 108
A.3.20 CAEX complex type CAEXObject . 109
A.3.21 CAEX complex type InterfaceClassType . 110
A.3.22 CAEX complex type InterfaceFamilyType. 113
A.3.23 CAEX complex type InternalElementType . 115
A.3.24 CAEX complex type RoleClassType . 123
A.3.25 CAEX complex type RoleFamilyType . 125
A.3.26 CAEX complexType SourceDocumentInformationType . 128
A.3.27 CAEX complex type SystemUnitClassType . 129
A.3.28 CAEX complex type SystemUnitFamilyType . 136
A.3.29 CAEX simpleType ChangeMode . 138
Annex B (informative) Examples of PCE requests . 139
Annex C (normative) Full XML schema of the CAEX model . 149
Annex D (informative) CAEX modelling examples . 155
D.1 CAEX Attribute Type Library definition for additional attributes . 155
D.2 Example of CAEX InterfaceLib definition . 156
D.3 Example of a CAEX RoleLib definition . 157
D.4 Example CAEX definition of PCE relevant P&ID information . 158
Annex E (informative) List of major changes and extensions of the second edition . 163
Bibliography . 166

– 4 – IEC 62424:2016  IEC 2016

Figure 1 – Information flow between P&ID and PCE tool . 11
Figure 2 – Organization of PCE requests . 20
Figure 3 – General representation of a PCE-Request in a P&ID . 21
Figure 4 – Multi-sensing element . 21
Figure 5 – Local interface . 22
Figure 6 – Manually operated switch in local control panel . 22
Figure 7 – Pressure indication in central control room by a central control system . 22
Figure 8 – Example of PCE request reference designation . 26
Figure 9 – Example of flow measurement with indication in the CCR delivered by
vendor A specified by typical identification A20. 26
Figure 10 – Example of pH-measurement with indication in the CCR . 26
Figure 11 – Example of flow measurement with indication in the CCR and high and
low alarm . 27
Figure 12 – Flow measurement with indication in the CCR and high alarm and a high-
high switching function . 27
Figure 13 – Flow measurement with indication in the CCR and a high-high switch limit,
a high alarm, a low alarm and a low-low switch limit for a safety function . 27
Figure 14 – GMP relevant, safety relevant and quality relevant flow measurement with
indication in the CCR . 28
Figure 15 – Control function . 28
Figure 16 – Safety relevant control function . 29
Figure 17 – P&ID elements and associations (PCE relevant items are shown in dark
lines) . 30
Figure 18 – Process data model (PCE relevant items are shown in dark lines) . 31
Figure 19 – PCE request data model . 32
Figure 20 – CAEX data model of major PCE request related attributes . 35
Figure 21 – XML code of the attribute type library . 35
Figure 22 – Example of two plant sections and a signal connection via external
interfaces . 36
Figure 23 – Simplified CAEX model of indirect links between PCE requests across
different plant hierarchy items . 37
Figure 24 – Simplified CAEX model of indirect links between PCE requests across
different plant hierarchy items . 38
Figure 25 – Example of two plant sections and a direct connection . 39
Figure 26 – Simplified CAEX model of direct links between PCE requests across
different sections of a plant . 39
Figure 27 – XML code of the simplified CAEX model . 40
Figure A.1 – XML text of the CAEX source document information . 49
Figure A.2 – CAEX architecture of a SystemUnitClass . 51
Figure A.3 – Example of a SystemUnitClassLib . 51
Figure A.4 – XML code of the example of a SystemUnitClassLib . 52
Figure A.5 – Examples of attributes . 53
Figure A.6 – XML code of the example . 54
Figure A.7 – Example of an AttributeTypeLib and its application in an instance
hierarchy . 55

Figure A.8 – XML code of the AttributeTypeLib example . 55
Figure A.9 – Example of an InterfaceClassLib . 56
Figure A.10 – XML code of the example of an InterfaceClassLib . 57
Figure A.11 – Second example of an InterfaceClassLib and the usage of nested
interfaces . 57
Figure A.12 – XML code of the second example . 58
Figure A.13 – Usage of Links . 59
Figure A.14 – XML code for the usage of links . 59
Figure A.15 – Example of a RoleClassLib . 60
Figure A.16 – Relations in CAEX . 61
Figure A.17 – XML description of the relations example . 62
Figure A.18 – XML text of the InstanceHierarchy of the relations example . 62
Figure A.19 – XML text of the SystemUnitClassLib of the relations example . 62
Figure A.20 – Example of a parent-child-relation between CAEX InternalElements . 63
Figure A.21 – Example for a hierarchical plant structure . 63
Figure A.22 – Example of a parent-child relation between classes . 64
Figure A.23 – Multiple crossed structures . 67
Figure A.24 – Example for mirror attributes and restructured mirror objects . 67
Figure A.25 – CAEX role concept . 70
Figure A.26 – CAEX data definition for use case 1 . 70
Figure A.27 – CAEX data definition for use case 2 . 71
Figure A.28 – CAEX data definition for use case 3 . 71
Figure A.29 – XML code for use case 3 . 72
Figure A.30 – Multiple role support . 73
Figure A.31 – XML code of the multiple role support example . 74
Figure A.32 – CAEX data definition of a MappingObject . 75
Figure A.33 – XML code for the data definition of a MappingObject . 76
Figure A.34 – Distribution of data in several CAEX files . 77
Figure A.35 – Referencing of external CAEX files . 77
Figure A.36 – XML code for referencing of external CAEX files . 77
Figure A.37 – Example of how to use alias names . 78
Figure A.38 – XML code for the alias example . 78
Figure B.1 – Local level indication, 1 process connection . 139
Figure B.2 – Local level indication, 2 process connections . 139
Figure B.3 – Local flow indication . 139
Figure B.4 – Local pressure indication . 139
Figure B.5 – Local temperature indication . 139
Figure B.6 – Local control panel, pressure indication, high alarm . 140
Figure B.7 – Local temperature indication, CCR temperature high alarm . 140
Figure B.8 – Local pressure indication, CCR pressure high alarm and switch . 140
Figure B.9 – CCR flow indication, device information: Orifice Plate . 140
Figure B.10 – CCR pressure indication, low, low low and high alarm . 140
Figure B.11 – CCR temperature indication and registration . 141

– 6 – IEC 62424:2016  IEC 2016
Figure B.12 – CCR level indication and registration, 1 process connection . 141
Figure B.13 – CCR level indication, 2 process connections . 141
Figure B.14 – Two flow indications and flow ratio control in CCR . 141
Figure B.15 – CCR flow indication and high alarm, flow control, control valve with extra
interlock and open/close indication . 142
Figure B.16 – Local pressure indication, CCR pressure indication, high alarm and high
high safety relevant switch; representation of transmitters with integrated local display
(if not otherwise defined in a specification of the field device) . 142
Figure B.17 – Local pressure indication, CCR pressure indication, alarms and switches . 142
Figure B.18 – CCR pressure indication, high and low alarm, safety relevant switch
action on on/off valve . 143
Figure B.19 – Switched valve with on/off indication and switching action, safety
relevant switched valve . 143
Figure B.20 – Pressure restriction . 143
Figure B.21 – Flow restriction . 143
Figure B.22 – PT compensated flow control, safety-relevant pressure switch (two out of
three (2oo3) shutdown), switched control valve with on/off indication and switching
action at open position . 144
Figure B.23 – CCR temperature control, additional manual switch actions from CCR
with indication and local control panel . 144
Figure B.24 – Motor typical, local on/off control, CCR off control, current, fault with
alarm and running indication . 145
Figure B.25 – Multivariable controller . 145
Figure B.26 – On/off valve with position indication . 146
Figure B.27 – On/off valve with safety relevant switch and position indication . 146
Figure B.28 – Level control with continuous controller . 146
Figure B.29 – Level control with on/off switch . 146
Figure B.30 – Cascade control for temperature as control input, flow control as follow-
up controller . 147
Figure B.31 – Safety directed high control to a subsequent valve, manual control for
reset function and manual control for manual/automatic switch of the valve, valve with
open/close indication and safety-relevant switch to subsequent valve . 147
Figure B.32 – Flow control in CCR . 147
Figure B.33 – Temperature control with high alarm and high switch . 148
Figure B.34 – Manual control from CCR . 148
Figure B.35 – Flow measurement with display and alarms in CCR, high high switch on
process control function and switch on/off valve . 148
Figure B.36 – Local P-/F-/T-/S- control without auxiliary power (stand-alone) . 148
Figure C.1 – Full XML text of the CAEX Schema file “CAEX_ClassModel_V.3.0.xsd” . 154
Figure D.1 – Attribute type library with additional PCE request related attributes . 155
Figure D.2 – XML code of the Attribute type library . 156
Figure D.3 – Example of CAEX interface library . 156
Figure D.4 – XML code of the example CAEX interface library . 156
Figure D.5 – Example CAEX role library illustrating the modeling of a PCE request role
referencing PCE request related attributes . 157
Figure D.6 – XML code for the example CAEX role library . 158
Figure D.7 – Example P&ID data to be mapped with CAEX . 159

Figure D.8 – CAEX model of the example described in Figure D.7 . 160
Figure D.9 – XML code of the example described in Figure D.7 . 162

Table 1 – Abbrevations . 17
Table 2 – PCE categories . 23
Table 3 – PCE processing function . 24
Table 4 – Sequence combinations . 25
Table 5 – PCE processing functions for final controlling equipments . 25
Table 6 – P&ID attributes relevant in PCE environment. 41
Table 7 – Data handling attributes . 41
Table A.1 – XML notation conventions . 42
Table A.2 – CAEX data types and elements . 43

– 8 – IEC 62424:2016  IEC 2016
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
REPRESENTATION OF PROCESS CONTROL ENGINEERING –
REQUESTS IN P&I DIAGRAMS AND DATA EXCHANGE
BETWEEN P&ID TOOLS AND PCE-CAE TOOLS

FOREWORD
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International Standard IEC 62424 has been prepared by IEC technical committee 65:
Industrial-process measurement, control and automation.
This second edition cancels and replaces the first edition published in 2008. This edition
constitutes a technical revision.
This second edition is a compatible extension of the first edition. The main changes and
extensions are detailed in Annex E and are summarized below:
a) updated definitions and new definitions;
b) identification replaced with reference designation;
c) updated PCE categories and process functions;
d) CAEX version 3.0, introduction of:
• native multiple role support;

• nested interfaces;
• life cycle meta information;
• a separate Attribute library;
• updated examples;
e) updated electronic data model of the PCE request:
• new normative attribute library for basic PCE request attributes;
• new informative extended attribute library for further PCE request attributes;
• new informative electronic data model for the PCE request.
The text of this standard is based on the following documents:
CDV Report on voting
65/544/CDV 65/560B/RVC
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.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC website 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 62424:2016  IEC 2016
INTRODUCTION
Efficient process engineering requires highly sophisticated tools for the different needs of the
involved work processes and departments. These engineering tools are normally specialized
in Process Design (PD), in Process Control Engineering (PCE), etc. Therefore, a working
interoperability is essential to optimize the engineering process in total. Thus, the definition of
a harmonized interface and data management is a core task to ensure a smooth workflow
during the whole project and to guarantee data consistency in the different tools.
This standard defines procedures and specifications for the exchange of PCE relevant data
provided by the Piping and Instrumentation Diagram (P&ID) tool. The basic requirements for a
change management procedure are described. A generally accepted technology for machine
information exchange, the Extensible Markup Language (XML) is used. Hereby, a common
basis is given for information integration.
However, a definition for uniform semantics is still necessary. CAEX (Computer Aided
Engineering eXchange) as it is defined in this document is an appropriate data format for this
purpose. This concept of data exchange is open for different applications.
The main task of a data exchange is transporting/synchronizing information from the P&ID
database to the PCE databases and vice versa. The owner's reference designation system
and a unique description of the processing requirement is the key for a unique identification.
For detailed information about representation of PCE loops in P&IDs see Clause 6.
The data exchange system may be a stand-alone, vendor independent application or a
module in an engineering environment. The data between a P&ID tool and a PCE tool and
vice versa is exchanged via CAEX.
After the data exchange, there are three places where information about the plant is stored.
Both the proprietary databases of the considered tools include private and common
information. Both are stored at different places and in different divisions that are working on
them. Hereby, the intermediate database CAEX only stores common information. In a wider
approach, the intermediate database should store both common and private information. This
becomes important if a third application is connected to the neutral database. If the
intermediate database is used as a temporary data stream only (without storing the
information in a file), the information will be lost after processing the data conciliation.
Figure 1 illustrates the information flow for the P&ID and the PCE database reconciliation.
The data exchange is done via a neutral intermediate CAEX database, not directly from
database to database. The intermediate CAEX database should be a file (for file based data
exchange) or a stream (for network based data exchange). The term “CAEX database” within
this standard has to be understood in this way, it does not denominate a database product as
for example SQL.
Annex C of this standard contains the full XML schema of the CAEX Model. It is attached to
this publication in XSD format.
NOTE Buyers of this publication can copy it for their own purposes only in the required amount.

IEC
Figure 1 – Information flow between P&ID and PCE tool

– 12 – IEC 62424:2016  IEC 2016
REPRESENTATION OF PROCESS CONTROL ENGINEERING –
REQUESTS IN P&I DIAGRAMS AND DATA EXCHANGE
BETWEEN P&ID TOOLS AND PCE-CAE TOOLS

1 Scope
This International Standard specifies how process control engineering requests are
represented in a P&ID for automatic transferring data between P&ID and PCE tool and to
avoid misinterpretation of graphical P&ID symbols for PCE.
It also defines the exchange of process control engineering request relevant data between a
process control engineering tool and a P&ID tool by means of a data transfer language (called
CAEX). These provisions apply to the export/import applications of such tools.
The representation of the PCE functionality in P&IDs will be defined by a minimum number of
rules to clearly indicate their category and processing function, independent from the
technique of realization (see Clause 6). The definition of graphical symbols for process
equipment (e.g. vessels, valves, columns, etc.), their implementation and rules for the
reference designation system are not in the scope of this standard. These rules are
independent from this standard.
Clause 7 specifies the data flow between the different tools and the data model CAEX.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and
are indispensable for its application. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 61511-1, Functional safety – Safety instrumented systems for the process industry sector
– Part 1: Framework, definitions, system, hardware and application programming
requirements
IEC 81346-
...