IEC 61804-2:2006

Function blocks (FB) for process control - Part 2: Specification of FB concept

IEC 61804-2:2006 Specifies FB (Function Bloks) by using the result of harmonization work as regards several elements:
- the device model which defines the components of an IEC 61804-2 conformant device;
- conceptual specifications of FBs for measurement, actuation and processing. This includes general rules for the essential features to support control, whilst avoiding details which stop innovation as well as specialization for different industrial sectors. It defines a subset of the requirements of IEC 61804-1 (hereafter referred to as Part 1) only, while Part 1 describes requirements for a distributed system.

Blocs fonctionnels (FB) pour les procédés industriels - Partie 2: Spécification du concept de FB

L'IEC 61804-2:2006 est applicable aux blocs fonctionnels (FB) pour les procédés industriels. Elle spécifie les blocs fonctionnels sur la base des résultats du travail d'harmonisation concernant plusieurs éléments. Cette deuxième édition, ainsi que la première édition de la CEI 61804-3, annule et remplace la première édition parue en 2004 de la CEI 61804-2. Elle constitue une révision technique et inclut les modifications suivantes:
- transfert des articles spécifiques au langage EDDL dans la CEI 61804-3;
- les paragraphes 4.1 et 4.2 spécifiques aux blocs fonctionnels, ainsi que les Articles 5, 6, 7 et 8 ne sont pas modifiés. La présente version bilingue (2014-04) correspond à la version anglaise monolingue publiée en 2006-09.

General Information

• Status: Published
• Publication Date: 11-Sep-2006
• ICS: 25.040.40 - Industrial process measurement and control
• ICS: 35.240.50 - IT applications in industry
• Technical Committee: SC 65E - Devices and integration in enterprise systems
• Drafting Committee: WG 7 - TC 65/SC 65E/WG 7
• Current Stage: DELPUB - Deleted Publication
• Completion Date: 10-Jan-2018

Relations

• Revised: IEC 61804-2:2018 - Function blocks (FB) for process control and electronic device description language (EDDL) - Part 2: Specification of FB concept
• Effective Date: 05-Sep-2023
• Revises: IEC 61804-2:2004 - Function blocks (FB) for process control - Part 2: Specification of FB concept and Electronic Device Description Language (EDDL)
• Effective Date: 05-Sep-2023

Standards Content (Sample)

INTERNATIONAL IEC
STANDARD 61804-2
Second edition
2006-09
Function blocks (FB) for process control –
Part 2:
Specification of FB concept
Reference number
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INTERNATIONAL IEC
STANDARD 61804-2
Second edition
2006-09
Function blocks (FB) for process control –
Part 2:
Specification of FB concept
 IEC 2006  Copyright - all rights reserved
No part of this publication may be reproduced or utilized in any form or by any means, electronic or
mechanical, including photocopying and microfilm, without permission in writing from the publisher.
International Electrotechnical Commission, 3, rue de Varembé, PO Box 131, CH-1211 Geneva 20, Switzerland
Telephone: [phone] Telefax: [phone] E-mail: [e-mail] Web: www.iec.ch
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For price, see current catalogue

– 2 – 61804-2  IEC:2006(E)
CONTENTS
FOREWORD.4

INTRODUCTION.6

1 Scope.7

2 Normative references .7

3 Terms, definitions and abbreviated terms and acronyms.8

3.1 Terms and definitions .8

3.2 Abbreviated terms and acronyms .14
4 General Function Block (FB) definition and EDD model .14
4.1 Device structure (device model) .14
4.2 Block combinations .25
5 Detailed block definition .28
5.1 General .28
5.2 Application FBs .28
5.3 Component FBs .36
5.4 Technology Block .36
5.5 Device (Resource) Block .45
5.6 Algorithms common to all blocks .47
6 FB Environment.49
7 Mapping to System Management.49
8 Mapping to Communication .49
9 Conformance statement.51

Annex A (informative) Parameter description .52
Annex B (normative) IEC 61804 Conformance Declaration .58

Bibliography.59

Figure 1 – Position of the IEC 61804 series related to other standards and products .6
Figure 2 – FB structure is derived out of the process (P&ID view) .15
Figure 3 – FB structure may be distributed between devices.16

Figure 4 – IEC 61804 FBs can be implemented in different devices .17
Figure 5 – General components of devices .17
Figure 6 – Block types of IEC 61804 .18
Figure 7 – IEC 61804 block overview (graphical representation not normative) .19
Figure 8 – UML class diagram of the device model .22
Figure 9 – Measurement process signal flow.26
Figure 10 – Actuation process signal flow .26
Figure 11 – Application process signal flow.27
Figure 12 – Analog Input FB .28
Figure 13 – Analog Output FB.30
Figure 14 – Discrete input FB .31
Figure 15 – Discrete Output FB.32

61804-2  IEC:2006(E) – 3 –
Figure 16 – Calculation FB.34

Figure 17 – Control FB.35

Figure 18 – Temperature Technology Block .36

Figure 19 – Pressure Technology Block .39

Figure 20 – Modulating actuation technology block .41

Figure 21 – On/Off Actuation Technology Block .43

Figure 22 – Harel state chart .46

Figure 23 – Application structure of ISO OSI Reference Model .49

Figure 24 – Client/Server relationship in terms of OSI Reference Model .50
Figure 25 – Mapping of IEC 61804 FBs to APOs.50

Table 1 – References of model elements .21
Table 2 – Variables and parameter description template .24
Table 3 – Example of temperature sensors of Sensor_Type.37
Table 4 – Device status state table .45
Table 5 – Device status transition table .46
Table A.1 – Parameter description .52
Table B.1 – Conformance (sub)clause selection table.58
Table B.2 – Contents of (sub)clause selection tables .58

– 4 – 61804-2  IEC:2006(E)
INTERNATIONAL ELECTROTECHNICAL COMMISSION

___________
FUNCTION BLOCKS (FB) FOR PROCESS CONTROL –

Part 2: Specification of FB concept

FOREWORD
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The International Electrotechnical Commission (IEC) draws attention to the fact that it is claimed that compliance
with this document may involve the use of patents
U.S. Patent No. 5,333,114
U.S. Patent No. 5,485,400
U.S. Patent No. 5,825,664
U.S. Patent No. 5,909,368
U.S. Patent Pending No. 08/916,178
Australian Patent No. 638507
Canadian Patent No. 2,066,743
European Patent No. 0495001
Validated in:
UK – Patent No. 0495001
France – Patent No. 0495001
Germany – Patent No. 69032954.7
Netherlands – Patent No. 0495001
Japan Patent No. 3137643
61804-2  IEC:2006(E) – 5 –
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Attention: President.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights

other than those identified above. IEC shall not be held responsible for identifying any or all such patent rights.

This International Standard has been prepared by subcommittee 65C: Digital communications,
of IEC technical committee 65: Industrial-process measurement and control.
This second edition, together with the first edition of IEC 61804-3, cancels
...

IEC 61804-2 ®
Edition 2.0 2006-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Function blocks (FB) for process control –
Part 2: Specification of FB concept

Blocs fonctionnels (FB) pour les procédés industriels –
Partie 2: Spécification du concept de FB

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IEC 61804-2 ®
Edition 2.0 2006-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Function blocks (FB) for process control –

Part 2: Specification of FB concept

Blocs fonctionnels (FB) pour les procédés industriels –

Partie 2: Spécification du concept de FB

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX XA
ICS 25.040.40; 35.240.50 ISBN 978-2-8322-1459-6

– 2 – IEC 61804-2:2006 © IEC 2006

CONTENTS
FOREWORD . 4

INTRODUCTION . 6

1 Scope . 7

2 Normative references . 7

3 Terms, definitions and abbreviated terms and acronyms . 8

3.1 Terms and definitions . 8

3.2 Abbreviated terms and acronyms . 14
4 General Function Block (FB) definition and EDD model . 14
4.1 Device structure (device model) . 14
4.2 Block combinations . 25
5 Detailed block definition . 28
5.1 General . 28
5.2 Application FBs . 28
5.3 Component FBs . 36
5.4 Technology Block . 36
5.5 Device (Resource) Block . 45
5.6 Algorithms common to all blocks . 47
6 FB Environment . 49
7 Mapping to System Management . 49
8 Mapping to Communication . 49
9 Conformance statement . 51

Annex A (informative) Parameter description . 52
Annex B (normative) IEC 61804 Conformance Declaration . 58

Bibliography . 59

Figure 1 – Position of the IEC 61804 series related to other standards and products . 6
Figure 2 – FB structure is derived out of the process (P&ID view) . 15
Figure 3 – FB structure may be distributed between devices . 16

Figure 4 – IEC 61804 FBs can be implemented in different devices . 17
Figure 5 – General components of devices . 17
Figure 6 – Block types of IEC 61804 . 18
Figure 7 – IEC 61804 block overview (graphical representation not normative) . 19
Figure 8 – UML class diagram of the device model . 22
Figure 9 – Measurement process signal flow. 26
Figure 10 – Actuation process signal flow . 26
Figure 11 – Application process signal flow. 27
Figure 12 – Analog Input FB . 28
Figure 13 – Analog Output FB . 30
Figure 14 – Discrete input FB . 31
Figure 15 – Discrete Output FB . 32

Figure 16 – Calculation FB. 34

Figure 17 – Control FB . 35

Figure 18 – Temperature Technology Block . 36

Figure 19 – Pressure Technology Block . 39

Figure 20 – Modulating actuation technology block . 41

Figure 21 – On/Off Actuation Technology Block . 43

Figure 22 – Harel state chart . 46

Figure 23 – Application structure of ISO OSI Reference Model . 49

Figure 24 – Client/Server relationship in terms of OSI Reference Model . 50
Figure 25 – Mapping of IEC 61804 FBs to APOs . 50

Table 1 – References of model elements . 21
Table 2 – Variables and parameter description template . 24
Table 3 – Example of temperature sensors of Sensor_Type . 37
Table 4 – Device status state table . 45
Table 5 – Device status transition table . 46
Table A.1 – Parameter description . 52
Table B.1 – Conformance (sub)clause selection table . 58
Table B.2 – Contents of (sub)clause selection tables . 58

– 4 – IEC 61804-2:2006 © IEC 2006

INTERNATIONAL ELECTROTECHNICAL COMMISSION

___________
FUNCTION BLOCKS (FB) FOR PROCESS CONTROL –

Part 2: Specification of FB concept

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 participat
...