SIST EN IEC 63522-28:2025

Electrical relays - Tests and measurement - Part 28: Thermoelectric electromotive force (e.m.f.)

IEC 63522-28:2025 This part of IEC 63522 is used for testing all kinds of electrical relays and for evaluating their ability to perform under expected conditions of transportation, storage and all aspects of operational use. This document defines a standard test method for thermoelectric electromotive force (e.m.f.).

Elektrische Relais - Mess- und Prüfverfahren - Teil 28: Thermoelektrische elektromotorische Kraft (EMK)

Relais électriques - Essais et mesurages - Partie 28: Force électromotrice (f.é.m.) thermoélectrique

IEC 63522-28:2025 La présente partie de l'IEC 63522 traite des essais de tous les types de relais électriques et elle évalue leur aptitude à fonctionner dans les conditions prévues de transport, de stockage et dans tous les aspects de leur utilisation opérationnelle. Le présent document définit une méthode d’essai normalisée pour la force électromotrice (f.é.m.) thermoélectrique.

Električni releji - Preskusi in meritve - 28. del Potencial za termospoje (EMF)

Ta del standarda IEC 63522 se uporablja za preskušanje vseh vrst električnih relejev in vrednotenje njihove zmožnosti delovanja v pričakovanih pogojih med transportom in skladiščenjem ter v vseh vidikih operativne uporabe.
OPOMBA 1: Primeri električnih relejev za potrebe tega dokumenta vključujejo elektromehanske releje, releje reed, kontakte reed, stikala reed, polprevodniške releje, časovne releje in njihove tehnološke kombinacije.
Ta dokument določa standardno preskusno metodo za potencial za termospoje (EMF).
OPOMBA 2: Če so na obeh koncih pritrjene različne kovine in se temperature stikov razlikujejo, bo tok v tokokrogu tekel v eno smer. Lastna napetost, ki povzroča ta tok, se imenuje potencial za termospoje.

General Information

• Status: Published
• Public Enquiry End Date: 31-Jul-2024
• Publication Date: 25-Jun-2025
• ICS: 29.120.70 - Relays
• Technical Committee: ISS EIT.ERE - All-or-nothing electrical relays
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 11-Jun-2025
• Due Date: 16-Aug-2025
• Completion Date: 26-Jun-2025
• Ref Project: EN IEC 63522-28:2025 - Electrical relays - Tests and measurements - Part 28: Thermoelectric electromotive force (e.m.f.)

Overview

SIST EN IEC 63522-28:2025 is a European standard that specifies the test methods and measurement procedures for assessing the thermoelectric electromotive force (e.m.f.) in electrical relays. Developed by the European Committee for Electrotechnical Standardization (CENELEC) in alignment with the International Electrotechnical Commission (IEC) standards, this regulation ensures that electrical relays perform reliably under conditions such as transportation, storage, and operational use. Part 28 of the IEC 63522 series focuses on thermoelectric effects in relay contacts, providing a standardized way to measure e.m.f. generated by temperature differences within relay components.

Key Topics

• Thermoelectric electromotive force (e.m.f.): This force arises when two dissimilar metals are joined and subjected to different temperatures, causing current flow due to temperature gradients at the junction.
• Scope of application: Applies to all types of electrical relays, including electromechanical relays, reed relays, reed switches, solid-state relays, and time relays.
• Test conditions: The relay is tested at its maximum allowable operating temperature with the coil energized at rated voltage, while voltage across relay contacts connected via copper wires is measured.
• Test procedure:
  • Attach relay make contacts to bare copper wires (0.5 mm² cross-section).
  • Maintain measurement equipment at room temperature.
  • Achieve thermal equilibrium or limit test duration to 4 hours.
  • Measure e.m.f. across the copper wires.
• Evaluation criteria: The measured thermoelectric e.m.f. must not exceed specified limits established prior to testing.
• Documentation: Test reports must include soldering method, materials used, ambient temperature, e.m.f. limits, and measured values for full reproducibility.

Applications

This standard is essential for manufacturers, quality assurance professionals, and testing laboratories involved in the design, production, and certification of electrical relays. By adhering to SIST EN IEC 63522-28:2025, stakeholders can:

• Ensure relay reliability: Confirm that relays do not generate excessive thermoelectric voltages that could interfere with relay operation or cause malfunction in electrical control systems.
• Enhance safety: Identify potential failure modes due to thermoelectric voltage generation, contributing to safer electrical installations.
• Support compliance: Meet both European and international regulatory requirements for electrical relay testing and certification.
• Optimize product design: Inform engineering adjustments to materials and contact assemblies to minimize adverse thermoelectric effects.
• Maintain performance under environmental stress: Verify that relays maintain electrical integrity after being subjected to temperature variations typical in transportation and operational environments.

Related Standards

• EN IEC 63522-0: General and Guidance
  This foundational document in the IEC 63522 series provides general principles, definitions, and guidance for relay testing and measurement, serving as a prerequisite for understanding and implementing Part 28.

• Other Parts of IEC 63522 series
  Additional parts focus on diverse relay testing protocols such as mechanical endurance, electrical endurance, environmental tests, and contact resistance measurements, forming a comprehensive toolkit for relay evaluation.

• ISO/IEC Directives and Electropedia Terminology
  The terminology used aligns with the IEC Electropedia and ISO Online Browsing Platform, ensuring consistency in definitions related to electrotechnical components and testing methodologies.

Keywords

EN IEC 63522-28, thermoelectric electromotive force, e.m.f., electrical relays testing, relay performance, relay measurement, relay reliability, CENELEC standards, IEC relay standards, relay operational testing, electrical relay certification, relay temperature effects, thermoelectromotive force, relay test procedure.

Standards Content (Sample)

SLOVENSKI STANDARD
01-september-2025
Električni releji - Preskusi in meritve - 28. del Potencial za termospoje (EMF)
Electrical relays - Tests and measurement - Part 28: Thermoelectric electromotive force
(e.m.f.)
Elektrische Relais - Mess- und Prüfverfahren - Teil 28: Thermoelektrische
elektromotorische Kraft (EMK)
Relais électriques - Essais et mesurages - Partie 28: Force électromotrice (f.é.m.)
thermoélectrique
Ta slovenski standard je istoveten z: EN IEC 63522-28:2025
ICS:
29.120.70 Releji Relays
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN IEC 63522-28

NORME EUROPÉENNE
EUROPÄISCHE NORM June 2025
ICS 29.120.70
English Version
Electrical relays - Tests and measurement - Part 28:
Thermoelectric electromotive force (e.m.f.)
(IEC 63522-28:2025)
Relais électriques - Essais et mesurages - Partie 28: Force Elektrische Relais - Mess- und Prüfverfahren - Teil 28:
électromotrice (f.é.m.) thermoélectrique Thermoelektrische elektromotorische Kraft (EMK)
(IEC 63522-28:2025) (IEC 63522-28:2025)
This European Standard was approved by CENELEC on 2025-05-28. 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 63522-28:2025 E

European foreword
The text of document 94/1127/FDIS, future edition 1 of IEC 63522-28, 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) 2026-06-30
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2028-06-30
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 63522-28:2025 was approved by CENELEC as a European
Standard without any modification.

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

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 63522-28 ®
Edition 1.0 2025-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Electrical relays – Tests and measurement –

Part 28: Thermoelectric electromotive force (e.m.f.)

Relais électriques – Essais et mesurages –

Partie 28: Force électromotrice (f.é.m.) thermoélectrique

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.120.70  ISBN 978-2-8327-0362-5

– 2 – IEC 63522-28:2025 © IEC 2025
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Test procedure . 6
4.1 Purpose . 6
4.2 Procedure . 6
4.3 Conditions to be specified . 6
5 Evaluation . 6
5.1 General . 6
5.2 Test report . 6

IEC 63522-28:2025 © IEC 2025 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ELECTRICAL RELAYS –
TESTS AND MEASUREMENTS –
Part 28: Thermoelectric electromotive force (e.m.f.)

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 standa
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