IEC PAS 63131:2017

System control diagram

IEC/PAS 63131:2017(E) defines a set of operational control functions (objects) and the associated logical diagram (System Control Diagram (SCD)), for use in the continuous control process industry – e.g. as used in Oil and Gas processes.
The main drivers for establishing this as a standard are the advantage of efficient engineering, implementation, and commissioning, as well as reuse of the control application across different suppliers of control systems. The diagrams give a logical representation that is suited for data transfer.
This PAS also includes a method of documenting sequences and their interaction with the control objects.

General Information

• Status: Published
• Publication Date: 06-Nov-2017
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• ICS: 25.040.40 - Industrial process measurement and control
• ICS: 75.200 - Petroleum products and natural gas handling equipment
• Technical Committee: TC 65 - Industrial-process measurement, control and automation
• Current Stage: PPUB - Publication issued
• Start Date: 30-Oct-2017
• Completion Date: 07-Nov-2017

Standards Content (Sample)

IEC PAS 63131 ®
Edition 1.0 2017-11
PUBLICLY AVAILABLE
SPECIFICATION
PRE-STANDARD
colour
inside
System control diagram
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IEC PAS 63131 ®
Edition 1.0 2017-11
PUBLICLY AVAILABLE
SPECIFICATION
PRE-STANDARD
colour
inside
System control diagram
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 25.040.40; 75.200 ISBN 978-2-8322-4889-8

– 2 – IEC PAS 63131:2017 © IEC 2017
CONTENTS
FOREWORD . 11
INTRODUCTION . 13
1 Scope . 16
2 Normative references . 16
3 Terms, definitions and abbreviated terms . 16
3.1 Terms and definitions . 16
3.2 Abbreviated terms . 21
4 The system control diagram (SCD) approach . 22
4.1 Conceptual definition . 22
4.2 Framework . 23
4.3 Life cycle concept . 23
4.4 Basic design (informative) . 24
4.4.1 General . 24
4.4.2 Basic system design . 24
4.4.3 Basic function design . 25
4.4.4 Basic application design . 25
4.4.5 Application design . 26
4.5 Alarm management . 27
Annex A (normative) System control diagram (SCD) function standard . 28
A.1 Overview. 28
A.1.1 General . 28
A.1.2 Compliance . 28
A.1.3 Positive logic . 28
A.1.4 Execution sequence of logic . 28
A.1.5 Functions used in SIF . 28
A.1.6 HMI presentation . 29
A.2 Terminal codes . 29
A.2.1 General . 29
A.2.2 Signal types (1.Character) . 30
A.2.3 Explanatory code (succeeding characters) . 31
A.2.4 Terminal description for function templates . 31
A.3 SCD control function template behaviour . 35
A.4 Function templates. 35
A.4.1 General . 35
A.4.2 Function template name convention . 36
A.4.3 CA – PID controller . 40
A.4.4 CS – Step control . 47
A.4.5 HA – Analogue input command . 53
A.4.6 HB – Binary input command. 55
A.4.7 KB – Sequence logic interface template . 57
A.4.8 LB – Safeguarding shutdown level . 59
A.4.9 MA – Monitoring of analogue process variables . 62
A.4.10 MAS – Analogue measurement acquisition from subsystems . 66
A.4.11 MB – Monitoring of binary (digital) process variables . 69
A.4.12 OA – Analogue output. 71
A.4.13 QA – Totalizer . 77

A.4.14 SB – Single binary signal for shutdown . 81
A.4.15 SBB – Breaker control template . 83
A.4.16 SBC – Coordinator for SBE . 89
A.4.17 SBE – Control of electrical equipment . 94
A.4.18 SBV – Control of pneumatic/hydraulic equipment . 100
A.4.19 Sequence logic . 106
Annex B (normative) SCD drawing standard . 110
B.1 Overview. 110
B.2 Content of SCDs . 111
B.2.1 Equipment . 111
B.2.2 Measuring instruments. 112
B.2.3 Functions . 112
B.2.4 Flow paths . 112
B.2.5 Information not shown on the SCDs . 113
B.2.6 Black box representation . 113
B.2.7 Parallel equipment . 113
B.3 Layout. 114
B.3.1 Readability . 114
B.3.2 The extent of information on SCDs . 114
B.3.3 Location of information on the SCDs . 114
B.3.4 Direction of flow . 114
B.3.5 Page connectors . 114
B.3.6 From P&ID/D&ID to SCD . 114
B.4 Symbols . 115
B.4.1 General . 115
B.4.2 Function template symbol . 115
B.4.3 Symbols for logic and arithmetic functions . 117
B.4.4 Extended connection line for EFB functions . 119
B.4.5 Parameter labels . 120
B.4.6 Signal line . 120
B.4.7 Process line . 121
B.4.8 Line connections. 122
B.4.9 Process and signal line crossing/jump . 123
B.4.10 Sequential flow chart lines . 123
B.4.11 Instruments . 124
B.4.12 Mechanical equipment . 124
B.4.13 Valves . 124
B.4.14 Electrical equipment . 127
B.4.15 Sequence symbols. 128
B.4.16 Reference symbols . 132
B.5 Tagging . 134
B.6 Terminal codes . 134
B.7 Symbol and font sizes . 135
B.8 Layers and colors . 140
B.9 Legend sheets . 141
B.9.1 General . 141
B.9.2 Part 1: Symbols and codes . 141
B.9.3 Part 2: System specific function templates and terminal definition codes . 141
B.9.4 Part 3: Applications typical . 142

– 4 – IEC PAS 63131:2017 © IEC 2017
B.10 Drawing frame and title block .
...