National foreword

This Published Document is the UK implementation of CLC IEC/TR 63201:2020. It is identical to IEC TR 63201:2019. It supersedes PD IEC TR 63201:2019, which is withdrawn.

The UK participation in its preparation was entrusted to Technical Committee PEL/121/1, Low voltage switchgear and controlgear.

A list of organizations represented on this committee can be obtained on request to its committee manager.

This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application.

Compliance with a British Standard cannot confer immunity from legal obligations.

This Published Document was published under the authority of the Standards Policy and Strategy Committee on 30 June 2019.

FOREWORD

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 participate in this preparatory work. International, governmental and non - governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.
The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international consensus of opinion on the relevant subjects since each technical committee has representation from all interested IEC National Committees.
IEC Public ations have the form of recommendations for international use and are accepted by IEC National Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any misinterpretation by any end user.
In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications transparently to the maximum extent possible in their national and regional publications. Any divergence between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.
IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any services carried out by independent certification bodies.
All users should ensure that they have the latest edition of this publication.
No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and members of its technical committees and IEC National Committees for any personal injury, property damage or other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC Publications.
Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is indispensable for the correct application of this publication.
Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of patent rights. IEC shall not be held responsible for identifying any or all such patent rights.

The main task of IEC technical committees is to prepare International Standards. However, a technical committee may propose the publication of a technical report when it has collected data of a different kind from that which is normally published as an International Standard, for example "state of the art".

IEC TR 63201, which is a technical report, has been prepared by subcommittee 1 2 1 A: Low - voltage switchgear and controlgear, of IEC technical committee 121: Switchgear and controlgear and their assemblies for low voltage.

The text of this technical report is based on the following documents:

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.

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.

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.

Introduction

Programmable electronics are now being integrated within switchgear and controlgear. For example, soft-starters, electronic overload relays, circuit-breakers with electronic trip units, proximity switches with built in micro-controllers and some accessories such as extension modules and control panels are using programmable electronics with embedded software called firmware. This embedded software often supports the main functions (see 3.3) provided by the equipment such as overcurrent protection and other important functions, e.g. alarm detection from monitoring devices.

The integration of embedded software within switchgear and controlgear should not degrade the integrity of their main functions compared to purely electromechanical equipment. Therefore, a minimum set of standard requirements for embedded software is provided by this document.

This document takes into account the existing best practices for developing embedded software within safety functions for automation given by IEC 61508‑3. Functional safety approach is mainly used in machinery, automotive, automation and process automation where safety functions are implemented with multiple components which should match a consistent level of integrity when combined. In other sectors, such as electric distribution and power control systems, key functions such as over-current release, residual current release, load monitoring, etc. should follow installation rules and coordination rules which are systematically safety and reliability related. Therefore, this document can be seen as providing the principles of the good practice given by IEC 61508‑3.

This document is also intended to provide an up-to-date method with regards to the supplement SE of UL 489.

The intention of this document is to provide guidance about:

risk assessment aspects in relation to embedded software;
embedded software evaluation method;
software architecture;
basic coding rules;
measures to control software errors;
software verification and its relationship with the validation of the equipment or system.

In this document, the term “software” is used as a generalized term for embedded software.

This Technical Report was approved by CENELEC on 2020-08-10.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom.

European foreword

This document (CLC IEC/TR 63201:2020) consists of the text of IEC/TR 63201:2019 prepared by SC 121A "Low-voltage switchgear and controlgear" of IEC/TC 121 "Switchgear and controlgear and their assemblies for low voltage".

Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights.

Endorsement notice

The text of the International Technical Report IEC/TR 63201:2019 was approved by CENELEC as a European Technical Report without any modification.

In the official version, for Bibliography, the following notes have to be added for the standards indicated:

1 Scope

This document provides information, and recommended minimum requirements related to embedded software supporting the main functions of switchgear and controlgear during the whole lifecycle of the equipment. It includes also the parameterization aspects and basics about secure coding standards.

This document can be used in addition to product standard requirements when not already covered.

This document is appropriate for new development or major changes in existing equipment.

This document is not intended to cover the functional safety of control systems for machinery or for automation which are covered by IEC 62061, ISO 13849-1 and IEC 6 1508 (all parts), neither the cybersecurity risk which are covered by ISO 27005, and IEC 62443 (all parts). It gives only some example of secure coding rules.

NOTE Future new publication IEC TS 632081 is under development for implementing embedded cyber security measures within switchgear and controlgear based on ISO 27005 and IEC 62443 (all parts).

2 Normative references

3 Terms and definitions

4 Risk assessment and identification of the main functions

5 Design management

5.1 Objective

5.2 Software management plan of the main functions

5.3 Configuration management

5.4 Change management

5.5 Defect management

5.6 System build and release processes

6 Manual parameterization of the embedded software

6.1 General

6.2 Influences on main function related parameters

6.3 Requirements for software-based manual parameterization

6.4 Verification of the parameterization tool

6.5 Documentation of software-based manual parameterization

7 Design lifecycle

7.1 General

7.2 Toolsusage

7.3 Software lifecycle

7.4 Requirements definition

7.5 Software architecture

7.6 Software unit design

7.7 Coding

7.8 Software unit test

7.9 Software integration test

7.10 Software testing

7.11 Docume ntation

7.12 Configuration and change management process

7.13 Verification and relationship with the validation of the equipment or system

Bibliography

PD CLC IEC/TR 63201:2020

Low-voltage switchgear and controlgear. Guidance for the development of embedded software

Current

Published:

31 Oct 2020