ISO 15519-2:2015

INTERNATIONAL ISO
STANDARD 15519-2
First edition
2015-06-01
Specifications for diagrams for
process industry —
Part 2:
Measurement and control
Spécifications pour schémas de l’industrie de traitement —
Partie 2: Mesurage et contrôle
Reference number
©
ISO 2015
© ISO 2015, Published in Switzerland
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ii © ISO 2015 – All rights reserved

Contents Page
Foreword .v
Introduction .vi
1 Scope .1
2 Normative references .1
3 Terms, definitions, and abbreviated terms .1
3.1 Terms related to control . 1
3.2 Document types . 3
3.3 Abbreviated terms . 3
4 Documentation and process control principles.3
4.1 Introduction . 3
4.2 Diagram types, structures, and life cycle aspects . 4
4.3 Process control interrelations . 5
4.4 Information exchange between process and control systems . 6
5 Exchange of process control information .7
5.1 Symbols for information exchange . 7
5.1.1 General. 7
5.1.2 Placement of information inside the PCI symbol. 8
5.1.3 Placement of information outside the PCI symbol . 9
5.2 Letter codes . 9
5.2.1 General. 9
5.2.2 Representation of letter codes for process variables . 9
5.2.3 Representation of letter codes for control functions.10
5.2.4 Sequence of letter codes for control functions .11
5.2.5 Modifying letter codes .12
5.3 Reference designation .13
6 Representation in general .13
6.1 General .13
6.2 Signal lines .13
6.3 Graphical symbols .14
6.3.1 General.14
6.3.2 Instruments with integrated display .14
6.3.3 Multifunction instruments .14
6.3.4 Instruments forming a group .15
6.3.5 Differentiating of representation .15
6.3.6 Graphical symbol “groups” in diagrams .15
7 Representation in diagrams .15
7.1 Introduction .15
7.2 Process flow diagram, PFD .16
7.2.1 Description . . .16
7.2.2 Application .16
7.2.3 Contents . .16
7.2.4 Representation .17
7.3 Process and instrumentation diagram, PID .18
7.3.1 Description . . .18
7.3.2 Application .18
7.3.3 Contents . .18
7.3.4 Representation .19
7.4 Process control diagram, PCD .20
7.4.1 Description . . .20
7.4.2 Application .21
7.4.3 Contents . .21
7.4.4 Representation .21
7.5 Typical diagrams, TYD .22
7.5.1 Description . . .22
7.5.2 Application .22
7.5.3 Contents . .22
7.5.4 Representation .22
Annex A (informative) Graphical symbols for connections main process equipment,
measurement, actuation, and control .24
Annex B (informative) Examples of representation of measurement, control, and
actuation tasks .34
Annex C (informative) Diagram examples .36
Annex D (informative) Information exchange between process and control system .40
Annex E (informative) Relationship between terms for closed loop control, measurement,
actuation, etc. .42
Bibliography .43
iv © ISO 2015 – All rights reserved

Foreword
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