IEC 62873-3-3:2022

Residual current operated circuit-breakers for household and similar use - Part 3-3: Specific requirements for devices with screw-type terminals for external untreated aluminium conductors and with aluminium screw-type terminals for use with copper or with aluminium conductors

IEC 62873-3-3:2022 applies to devices equipped with screw-type terminals of copper - or of alloys containing at least 58 % of copper (if worked cold) or at least 50 % of copper (if worked otherwise), or of other metal or suitably coated metal, no less resistant to corrosion than copper and having mechanical properties no less suitable – for use with untreated aluminium conductors, or with screw-type terminals of aluminium material for use with copper or aluminium conductors. This second edition cancels and replaces the first edition published in 2016. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition:
- Modification of scope to address other devices in addition to RCDs;
- Modification of Clause 8 so that IEC 62873-3-3 can be referred to by other product standards in addition to those for RCDs;
- Modification of 9.1 so that IEC 62873-3-3 can be referred to by other product standards in addition to those for RCDs.

General Information

• Status: Published
• Publication Date: 06-Nov-2022
• ICS: 29.120.50 - Fuses and other overcurrent protection devices
• Technical Committee: SC 23E - Circuit-breakers and similar equipment for household use
• Drafting Committee: WG 2 - TC 23/SC 23E/WG 2
• Current Stage: PPUB - Publication issued
• Start Date: 02-Dec-2022
• Completion Date: 07-Nov-2022

Relations

• Revises: IEC 62873-3-3:2016 - Residual current operated circuit-breakers for household and similar use - Part 3-3: Specific requirements for RCDs with screw-type terminals for external untreated aluminium conductors and with aluminium screw-type terminals for use with copper or with aluminium conductors
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 62873-3-3 ®
Edition 2.0 2022-11
INTERNATIONAL
STANDARD
Residual current operated circuit-breakers for household and similar use –
Part 3-3: Specific requirements for devices with screw-type terminals for
external untreated aluminium conductors and with aluminium screw-type
terminals for use with copper or with aluminium conductors
All rights reserved. Unless otherwise specified, 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
either IEC or IEC's member National Committee in the country of the requester. If you have any questions about IEC
copyright or have an enquiry about obtaining additional rights to this publication, please contact the address below or
your local IEC member National Committee for further information.

IEC Secretariat Tel.: [phone]
3, rue de Varembé [e-mail]
CH-1211 Geneva 20 www.iec.ch
Switzerland
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigendum or an amendment might have been published.

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committee, …). It also gives information on projects, replaced have access to up to date content tailored to your needs.
and withdrawn publications.
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The world's leading online dictionary on electrotechnology,
Stay up to date on all new IEC publications. Just Published
containing more than 22 300 terminological entries in English
details all new publications released. Available online and
and French, with equivalent terms in 19 additional languages.
once a month by email.
Also known as the International Electrotechnical Vocabulary

(IEV) online.
IEC Customer Service Centre - webstore.iec.ch/csc

If you wish to give us your feedback on this publication or
need further assistance, please contact the Customer Service
Centre: [e-mail].
IEC 62873-3-3 ®
Edition 2.0 2022-11
INTERNATIONAL
STANDARD
Residual current operated circuit-breakers for household and similar use –

Part 3-3: Specific requirements for devices with screw-type terminals for

external untreated aluminium conductors and with aluminium screw-type

terminals for use with copper or with aluminium conductors

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.120.50 ISBN 978-2-8322-6004-3

– 2 – IEC 62873-3-3:2022 © IEC 2022
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 Classification . 7
5 Characteristics of devices . 7
6 Marking and other product information . 7
7 Standard conditions for operation in service and for installation . 8
8 Requirements for construction and operation . 8
9 Tests . 9
9.1 General . 9
9.2 Test conditions . 10
9.3 Current cycling test . 11
9.3.1 General . 11
9.3.2 Preparation . 11
9.3.3 Test arrangement . 11
9.3.4 Temperature measurement . 12
9.3.5 Test method and acceptance criteria . 12
Bibliography . 18

Figure 1 – General arrangement for the test . 16
Figure 2 – Test specimen example 1 . 16
Figure 3 – Test specimen example 2 . 17
Figure 4 – Test specimen example 3 . 17
Figure 5 – Test specimen example 4 . 17
Figure 6 – Test specimen example 5 . 17

Table 1 – Marking for terminals . 8
Table 2 – Connectable cross-sections of aluminium conductors for screw-type
terminals . 8
Table 3 – List of tests according to the material of conductors and terminals . 9
Table 4 – Connectable conductors and their theoretical diameters . 10
Table 5 – Cross-sections (S) of aluminium test conductors corresponding to the rated
currents . 10
Table 6 – Test conductor length . 11
Table 7 – Equalizer and busbar dimensions . 12
Table 8 – Test current as a function of rated current . 14
Table 9 – Example of calculation for determining the average temperature deviation D. 14
Table 10 – Connectable cross-sections of copper conductors for screw-type terminals . 15
Table 11 – Test copper conductors corresponding to the rated currents . 15
Table 12 – Screw thread diameters and applied torques . 15

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
RESIDUAL CURRENT OPERATED CIRCUIT-BREAKERS
FOR HOUSEHOLD AND SIMILAR USE –

Part 3-3: Specific requirements for devices with screw-type terminals for
external untreated aluminium conductors and with aluminium screw-type
terminals for use with copper or with aluminium conductors

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 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.
2) 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.
3) IEC Publications 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.
4) 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.
5) 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.
6) All users should ensure that they have the latest edition of this publication.
7) 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.
8) 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.
9) 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.
IEC 62873-3-3 has been prepared by subcommittee 23E: Circuit breakers and similar
equipment for household use, of IEC technical committee 23: Electrical accessories. It is an
International Standard.
This second edition cancels and replaces the first edition published in 2016. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) Modification of scope to address other devices in addition to RCDs;
b) Modification of Clause 8 so that IEC 62873-3-3 can be referred to by other product standards
in addition to those for RCDs;

– 4 – IEC 62873-3-3:2022 © IEC 2022
c) Modification of 9.1 so that IEC 62873-3-3 can be referred to by other product standards in
addition to those for RCDs.
The text of this International Standard is based on the following documents:
Draft Report on voting
23E/1274/FDIS 23E/1306/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
A list of all parts of the IEC 62873 series published under the general title Residual current
operated circuit-breakers for household and similar use can be found on the IEC website.
The following differing practices of a less permanent nature exist in the countries indicated
below:
– NOTE 2 of Clause 1: the use of aluminium screw-type terminals for use with copper
conductors is not allowed (Austria, Australia and Germany);
– NOTE 2 of Clause 1: terminals for aluminium conductors only are not allowed (Austria and
Germany);
– NOTE 2 of Clause 1: the use of aluminium conductors is not allowed for final circuits in
household and similar installations e.g. offices, shops (Spain);
– NOTE 2 of Clause 1: the minimum cross-sectional area for aluminium conductors is 16 mm
(Denmark).
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/standardsdev/publications.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under 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.
INTRODUCTION
This doc
...

IEC 62873-3-3 ®
Edition 2.0 2022-11
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Residual current operated circuit-breakers for household and similar use –
Part 3-3: Specific requirements for RCDs devices with screw-type terminals for
external untreated aluminium conductors and with aluminium screw-type
terminals for use with copper or with aluminium conductors

All rights reserved. Unless otherwise specified, 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
either IEC or IEC's member National Committee in the country of the requester. If you have any questions about IEC
copyright or have an enquiry about obtaining additional rights to this publication, please contact the address below or
your local IEC member National Committee for further information.

IEC Secretariat Tel.: [phone]
3, rue de Varembé [e-mail]
CH-1211 Geneva 20 www.iec.ch
Switzerland
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigendum or an amendment might have been published.

IEC publications search - webstore.iec.ch/advsearchform IEC Products & Services Portal - products.iec.ch
The advanced search enables to find IEC publications by a Discover our powerful search engine and read freely all the
variety of criteria (reference number, text, technical publications previews. With a subscription you will always
committee, …). It also gives information on projects, replaced have access to up to date content tailored to your needs.
and withdrawn publications.
Electropedia - www.electropedia.org
IEC Just Published - webstore.iec.ch/justpublished
The world's leading online dictionary on electrotechnology,
Stay up to date on all new IEC publications. Just Published
containing more than 22 300 terminological entries in English
details all new publications released. Available online and
and French, with equivalent terms in 19 additional languages.
once a month by email.
Also known as the International Electrotechnical Vocabulary

(IEV) online.
IEC Customer Service Centre - webstore.iec.ch/csc

If you wish to give us your feedback on this publication or
need further assistance, please contact the Customer Service
Centre: [e-mail].
IEC 62873-3-3 ®
Edition 2.0 2022-11
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Residual current operated circuit-breakers for household and similar use –
Part 3-3: Specific requirements for RCDs devices with screw-type terminals for
external untreated aluminium conductors and with aluminium screw-type
terminals for use with copper or with aluminium conductors
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.120.50 ISBN 978-2-8322-6044-9
– 2 – IEC 62873-3-3:2022 RLV © IEC 2022
CONTENTS
FOREWORD . 3
INTRODUCTION . 2
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 8
4 Classification . 8
5 Characteristics of devices . 8
6 Marking and other product information . 9
7 Standard conditions for operation in service and for installation . 9
8 Requirements for construction and operation . 9
9 Tests . 10
9.1 General . 10
9.2 Test conditions . 13
9.3 Current cycling test . 14
9.3.1 General . 14
9.3.2 Preparation . 14
9.3.3 Test arrangement . 14
9.3.4 Temperature measurement . 15
9.3.5 Test method and acceptance criteria . 15
Bibliography . 23

Figure 1 – General arrangement for the test . 21
Figure 2 – Test specimen example 1 . 21
Figure 3 – Test specimen example 2 . 22
Figure 4 – Test specimen example 3 . 22
Figure 5 – Test specimen example 4 . 22
Figure 6 – Test specimen example 5 . 22

Table 1 – Marking for terminals . 9
Table 2 – Connectable cross-sections of aluminium conductors for screw-type
terminals . 10
Table 3 – List of tests according to the material of conductors and terminals . 11
Table 4 – Connectable conductors and their theoretical diameters . 13
Table 5 – Cross-sections (S) of aluminium test conductors corresponding to the rated
currents . 13
Table 6 – Test conductor length . 14
Table 7 – Equalizer and busbar dimensions . 15
Table 8 – Test current as a function of rated current . 17
Table 9 – Example of calculation for determining the average temperature deviation D. 18
Table 10 – Connectable cross-sections of copper conductors for screw-type terminals . 18
Table 11 – Test copper conductors corresponding to the rated currents . 19
Table 12 – Screw thread diameters and applied torques . 19

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
RESIDUAL CURRENT OPERATED CIRCUIT-BREAKERS
FOR HOUSEHOLD AND SIMILAR USE –

Part 3-3: Specific requirements for RCDs devices with screw-type
terminals for external untreated aluminium conductors and with
aluminium screw-type terminals for use with copper
or with aluminium conductors
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 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.
2) 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.
3) IEC Publications 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.
4) 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.
5) 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.
6) All users should ensure that they have the latest edition of this publication.
7) 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.
8) 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.
9) 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.
This redline version of the official IEC Standard allows the user to identify the changes made to
the previous edition IEC 62873-3-3:2016. A vertical bar appears in the margin wherever a change
has been made. Additions are in green text, deletions are in strikethrough red text.

– 4 – IEC 62873-3-3:2022 RLV © IEC 2022
IEC 62873-3-3 has been prepared by subcommittee 23E: Circuit breakers and similar
equipment for household use, of IEC technical committee 23: Electrical accessories. It is an
International Standard.
This second edition cancels and replaces the first edition published in 2016. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) Modification of scope to address other devices in addition to RCDs;
b) Modification of Clause 8 so that IEC 62873-3-3 can be referred to by other product standards
in addition to those for RCDs;
c) Modification of 9.1 so that IEC 62873-3-3 can be referred to by other product standards in
addition to those for RCDs.
The text of this International Standard is based on the following documents:
Draft Report on voting
23E/1274/FDIS 23E/1306/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
A list of all parts of the IEC 62873 series published under the general title Residual current
operated circuit-breakers for household and similar use can be found on the IEC website.
The following differing practices of a less permanent nature exist in the countries indicated
below:
– NOTE 2 of Clause 1: the use of aluminium screw-type terminals for use with copper
conductors is not allowed (Austria, Australia and Germany);
– NOTE 2 of Clause 1: terminals for aluminium conductors only are not allowed (Austria and
Germany);
– NOTE 2 of Clause 1: the use of aluminium conductors is not allowed for final circuits in
household and similar installations e.g. offices, shops (Spain);
– NOTE 2 of Clause 1: the minimum cross-sectional area for aluminium conductors is 16 mm
(Denmark).
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/standardsdev/publications.

The committee has decided that the contents of this document will remain unchanged until the
stability date indicated
...