IEC TR 63164-2:2020

Reliability of industrial automation devices and systems - Part 2: System reliability

IEC TR 63164-2:2020 provides guidance on the calculation of reliability data of automation systems which can be simplified as series, parallel or mixed structure based on reliability data of single devices and/or sub-systems, and on the form to present the data.
NOTE This procedure is only targeted to the reliability of automation systems, but not systems that embed automation systems, e.g. process plant.
Reliability is included in dependability, and this document is mainly focused on random hardware failures that affect reliability. Dependability is used as a collective term for the time-related quality characteristics of an item and additionally includes availability, recoverability, maintainability, maintenance support performance, and, in some cases, other characteristics such as durability, safety and security, which are all not in the scope of this Technical Report.

General Information

• Status: Published
• Publication Date: 21-Jul-2020
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• ICS: 25.040 - Industrial automation systems
• Technical Committee: TC 65 - Industrial-process measurement, control and automation
• Drafting Committee: WG 22 - TC 65/WG 22
• Current Stage: PPUB - Publication issued
• Start Date: 20-Aug-2020
• Completion Date: 22-Jul-2020

Standards Content (Sample)

IEC TR 63164-2 ®
Edition 1.0 2020-07
TECHNICAL
REPORT
Reliability of industrial automation devices and systems –
Part 2: System reliability
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IEC TR 63164-2 ®
Edition 1.0 2020-07
TECHNICAL
REPORT
Reliability of industrial automation devices and systems –

Part 2: System reliability
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 25.040 ISBN 978-2-8322-8663-0

– 2 – IEC TR 63164-2:2020 © IEC 2020
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Terms, definitions and abbreviated terms . 6
3.1 Terms and definitions . 6
3.2 Abbreviated terms . 9
4 System reliability . 9
5 Calculation of system reliability. 9
5.1 General . 9
5.2 Form to present reliability data . 10
5.3 Structures and calculations . 10
5.3.1 Basic formulas . 10
5.3.2 Series structures . 11
5.3.3 Parallel structures . 12
5.3.4 Mixed structures . 13
5.3.5 Summary . 14
Annex A (informative)  Examples of typical automation systems . 15
A.1 General . 15
A.2 Example for series structure of process automation system . 15
A.3 Example for mixed structure of process automation sub-system . 16
Annex B (informative) Methods to improve the system reliability . 18
B.1 General . 18
B.2 Methods to reduce systematic failure . 18
B.2.1 General . 18
B.2.2 Measures to avoid systematic failure . 18
B.2.3 Measures to control systematic failure . 18
B.3 Method of reducing random hardware failure . 19
B.3.1 Fault-tolerant design . 19
B.3.2 Error avoidance design . 19
B.3.3 System derating design . 19
Bibliography . 21

Figure 1 – Series reliability block diagram . 11
Figure 2 – Parallel reliability block diagram . 12
Figure 3 – General series-parallel (redundancy) reliability block diagram . 13
Figure 4 – Reduce the mixed structure . 13
Figure A.1 – A typical process automation system (aluminum smelting) . 15
Figure A.2 – Block diagram for aluminum smelting automation system . 16
Figure A.3 – Settling and washing process for aluminum smelting automation system . 16
Figure A.4 – Block diagram for settling and washing process . 17

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
RELIABILITY OF INDUSTRIAL AUTOMATION DEVICES AND SYSTEMS –

Part 2: System reliability
FOREWORD
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The main task of IEC technical committees is to prepare International Standards. However, a
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data of a different kind from that which is normally published as an International Standard, for
example "state of the art".
IEC TR 63164-2 has been prepared by IEC technical committee 65: Industrial-process
measurement, control and automation.
The text of this Technical Report is based on the following documents:
Enquiry draft Report on voting
65/771/DTR 65/796/RVDTR
Full information on the voting for the approval of this technical report can be found in the report
on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.

– 4 – IEC TR 63164-2:2020 © IEC 2020
A list of all parts in the IEC 63164 series, published under the general title Reliability of industrial
automation devices and systems, 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 "http://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.
A bilingual version of this publication may be issued at a later date.

INTRODUCTION
Under the background of Smart Manufacturing, new production modes such as mass
customization based on interconnected factories require real-time interconnection, frequent
switching and integration across different levels. Therefore, reliability is an important
requirement for automation systems in factories. Reliability data of automation systems is the
basis for maintenance planning e.g. stock-keeping of spare parts of a production line. An
automation system usually consists of several different devices or machines that are used in
series, parallel or mixed. This technical report gives guidance for system integrator on how to
evaluate the reliability of such entire systems.
This report is the second part of the series. This part concentrates on calculation of failure rates
or reliability values for systems based on failure rates or reliability values of single devices
depending on the structure of the system. This is necessary for system integrators or designers
to be able to calculate the reliability of an entire system from the reliability values of individual
devices (see IEC TS 63164-1).
Parts within IEC 63164 series are:
Part 1: Assurance of automation devices reliability data and specification of their source
Part 2: System reliability
Future parts may include following subjects:
– collecting reliability data for automation devices in the field;
– user guide.
– 6 – IEC TR 63164-2:2020 © IEC 2020
RELIABILITY OF INDUSTRIAL AUTOMATION DEVICES AND SYSTEMS –

Part 2: System reliability
1 Scope
This part of IEC 63164 provides guidance on the calculation of reliability data of automation
systems which can be simplified as series, parallel or mixed structure based on reliability data
of sin
...