IEC 62873-3-3:2022

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

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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
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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
...