EN IEC 63522-21:2025

SLOVENSKI STANDARD
01-december-2025
Električni releji - Preskusi in meritve - 7-21. del: Toplotna vzdržljivost
Electrical relays - Tests and Measurements - Part 7-21: Thermal Endurance
Elektrische Relais – Mess- und Prüfverfahren – Teil 21: Thermische Beständigkeit
Relais électriques - Essais et mesurages - Partie 7-21: Endurance thermique
Ta slovenski standard je istoveten z: EN IEC 63522-21:2025
ICS:
29.120.70 Releji Relays
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN IEC 63522-21

NORME EUROPÉENNE
EUROPÄISCHE NORM October 2025
ICS 29.120.70
English Version
Electrical relays - Tests and measurements - Part 21: Thermal
endurance
(IEC 63522-21:2025)
Relais électriques - Essais et mesurages - Partie 21: Elektrische Relais - Mess- und Prüfverfahren - Teil 21:
Endurance thermique Thermische Beständigkeit
(IEC 63522-21:2025) (IEC 63522-21:2025)
This European Standard was approved by CENELEC on 2025-09-15. CENELEC members are bound to comply with the CEN/CENELEC
Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.
Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC
Management Centre or to any CENELEC member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the
same status as the official versions.
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,
Türkiye and the United Kingdom.

European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2025 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN IEC 63522-21:2025 E

European foreword
The text of document 94/1064/FDIS, future edition 1 of IEC 63522-21, prepared by TC 94 "Electrical
relays" was submitted to the IEC-CENELEC parallel vote and approved by CENELEC as
The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2026-10-31
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2028-10-31
document have to be withdrawn
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.
This document is read in conjunction with EN IEC 63522-0:– .
Any feedback and questions on this document should be directed to the users’ national committee. A
complete listing of these bodies can be found on the CENELEC website.
Endorsement notice
The text of the International Standard IEC 63522-21:2025 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following notes have to be added for the standard indicated:
IEC 60038 NOTE Approved as EN 60038
IEC 60085 NOTE Approved as EN 60085
IEC 60947-2:2016 NOTE Approved as EN 60947-2:2017 (not modified)
IEC 60947-5-1 NOTE Approved as EN IEC 60947-5-1
IEC 61210 NOTE Approved as EN 61210

Under preparation. Stage at the time of publication: prEN IEC 63522-0:2024.
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments)
applies.
NOTE 1  Where an International Publication has been modified by common modifications, indicated by (mod),
the relevant EN/HD applies.
NOTE 2  Up-to-date information on the latest versions of the European Standards listed in this annex is available
here: www.cencenelec.eu.
Publication Year Title EN/HD Year
2 3
IEC 63522-0 Electrical relays - Tests and Measurements EN IEC 63522-0-
─ ─
- Part 0: General and Guidance
IEC 63522-6 2025 Electrical relays - Tests and measurements EN IEC 63522-6 2025
- Part 6: Contact-circuit resistance or
voltage drop
IEC 63522-7 2025 Electrical relays - Tests and measurements EN IEC 63522-7 2025
- Part 7: Functional tests
IEC 63522-8 2024 Electrical relays - Tests and measurements EN IEC 63522-8 2024
- Part 8: Timing
IEC 63522-22 - Electrical relays - Tests and measurements EN IEC 63522-22 -
- Part 22: Limiting continuous current

Under preparation. Stage at the time of publication: IEC CDV 63522-0:2024.
Under preparation. Stage at the time of publication: prEN IEC 63522-0:2024.
IEC 63522-21 ®
Edition 1.0 2025-08
INTERNATIONAL
STANDARD
Electrical relays – Tests and measurements –
Part 21: Thermal endurance
ICS 29.120.70  ISBN 978-2-8327-0652-7

IEC 63522-21:2025-08(en)
IEC 63522-21:2025 © IEC 2025
CONTENTS
FOREWORD . 2
1 Scope . 4
2 Normative references . 4
3 Terms and definitions . 4
4 Test procedure . 4
4.1 Purpose . 4
4.2 Procedure . 5
4.3 Conditions to be specified . 7
4.4 Test report . 7
5 Evaluation . 7
5.1 General . 7
5.1.1 Overview . 7
5.1.2 Intermediate and final measurements . 7
5.1.3 Primary evaluation parameters . 8
5.2 Test report . 8
Bibliography . 10

Figure 1 – Test sequence . 6

Table 1 – Conditions . 7
Table 2 – Duration level . 8
Table 3 – Table of test report . 9

IEC 63522-21:2025 © IEC 2025
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
Electrical relays - Tests and measurements -
Part 21: Thermal endurance
FOREWORD
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