EN IEC 61558-2-20:2025
(Main)Safety of transformers, reactors, power supply units and combinations thereof - Part 2-20: Particular requirements and tests for small reactors
Safety of transformers, reactors, power supply units and combinations thereof - Part 2-20: Particular requirements and tests for small reactors
IEC 61558-2-20:2022 is available as IEC 61558-2-20:2022 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.IEC 61558-2-20:2022 deals with the safety of small reactors for general applications. Small reactors incorporating electronic circuits are also covered by this document. This third edition cancels and replaces the second edition published in 2010. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition: - adjustment of structure and references in accordance with IEC 61558-1:2017. - additional Annex AA with references for characteristic parameter measurements. - additional Annex BB for associated reactors with frequencies above 500 Hz. - additional Annex CC for partial discharge. It has the status of a group safety publication in accordance with IEC Guide 104.
Sicherheit von Transformatoren, Drosseln, Netzgeräten und entsprechende Kombinationen - Teil 2-20: Besondere Anforderungen und Prüfungen an Kleindrosseln
Sécurité des transformateurs, bobines d'inductance, blocs d'alimentation et des combinaisons de ces éléments - Partie 2-20 : Exigences particulières et essais pour les petites bobines d'inductance
IEC 61558-2-20:2022 est disponible sous forme de IEC 61558-2-20:2022 RLV qui contient la Norme internationale et sa version Redline, illustrant les modifications du contenu technique depuis l'édition précédente.L'IEC 61558-2-20:2022 traite de la sécurité des petites bobines d'inductance pour applications d'ordre général. Les petites bobines d'inductance qui incorporent des circuits électroniques sont également couvertes par le présent document. Cette troisième édition annule et remplace la deuxième édition parue en 2010. Cette édition constitue une révision technique. Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente: - la structure et les références ont été alignées sur l'IEC 61558-1:2017; - l'Annexe AA a été ajoutée et contient des références pour les mesurages des paramètres caractéristiques; - l'Annexe BB a été ajoutée pour les bobines d'inductance associées dont les fréquences sont supérieures à 500 Hz; - l'Annexe CC a été ajoutée pour l'essai de décharge partielle. Il a le statut de publication groupée de sécurité conformément au l'IEC Guide 104.
Varnost transformatorjev, dušilk, napajalnikov in podobnih izdelkov - 2-20. del: Posebne zahteve in preskusi za majhne reaktorje
Ta del standarda IEC 61558 obravnava varnost majhnih reaktorjev za splošno uporabo. V tem dokumentu so zajeti tudi majhni reaktorji z vgrajenimi elektronskimi vezji.
OPOMBA 1: Varnost vključuje električne, toplotne in mehanske vidike.
Če ni navedeno drugače, od tu dalje izraz »transformator« ali »reaktor« zajema majhne reaktorje.
Ta dokument se uporablja za stacionarne ali prenosne, eno- ali večfazne, zračno hlajene (naravno ali umetno) reaktorje za splošno uporabo, vključno z izmeničnimi, predhodno magnetiziranimi in tokovno kompenziranimi samostojnimi ali povezanimi suhimi reaktorji. Navitja so lahko enkapsulirana ali neenkapsulirana.
Nazivna napajalna napetost ne presega 1000 V izmenične napetosti oziroma 1500 V enosmerne napetosti brez valovitosti, nazivna napajalna frekvenca in notranja obratovalna frekvenca pa ne presegata 100 MHz.
Ta dokument je mogoče uporabljati za reaktorje z osnovno frekvenco nad 500 Hz (glej dodatek BB).
Nazivna moč ne presega:
– 25 kVAR AC (25 kW DC) za enofazne reaktorje; – 50 kVAR AC (50 kW DC) za večfazne reaktorje.
Ta dokument se uporablja za reaktorje brez omejitev nazivne moči, o čemer se dogovorita kupec in proizvajalec.
Ta dokument se ne uporablja za:
– reaktorje, zajete v standardu IEC 60076-6, za nazivne napetosti nad 1 000 V; – dušilke za cevaste fluorescenčne sijalke, zajete v standardu IEC 61347-2-8; – dušilke za sijalke (razen cevastih fluorescenčnih sijalk), zajete v standardu IEC 61347‑2‑9;
– fiksne dušilke za dušenje elektromagnetnega motenja, zajete v skupini standardov IEC 60938. OPOMBA 2: Za reaktorje, napolnjene z izolirno tekočino ali snovjo v prahu, kot je pesek, so v obravnavi dodatne zahteve.
OPOMBA 3: Običajno so reaktorji namenjeni povezavi z opremo zaradi funkcionalnih zahtev opreme ali kadar je to potrebno v skladu s pravili namestitve ali specifikacijami drugih naprav. Zaščita pred električnim udarom se lahko zagotovi ali dopolni z drugimi deli ali elementi opreme, npr. z ohišjem.
OPOMBA 4: Reaktorji za posebne vrste uporabe bodo obravnavani v dopolnilnih normativnih dodatkih.
Po potrebi se upošteva naslednje:
– dodatne zahteve (iz drugih veljavnih standardov, nacionalnih pravil itd.) za reaktorje, ki so namenjeni za uporabo v vozilih, na ladjah in letalih; – ukrepi za zaščito ohišja in sestavnih delov v ohišju pred zunanjimi vplivi, kot so glive, mrčes, termiti, sončno sevanje in zmrzovanje; – različni pogoji za transport, shranjevanje in delovanje reaktorjev; – dodatne zahteve v skladu z drugimi ustreznimi standardi in nacionalnimi pravili, ki lahko veljajo za reaktorje, namenjene za uporabo v posebnih okoljih.
Za prihodnji tehnološki razvoj reaktorjev bo morda treba zvišati zgornjo mejo frekvenc, dotlej pa se ta dokument lahko uporablja kot vodilo.
Ta publikacija skupinske varnosti, ki se osredotoča na varnostne smernice, se uporablja predvsem kot standard o varnosti izdelka za izdelke, ki so omenjeni v okviru publikacije, vendar je namenjena tudi tehničnim odborom pri pripravi publikacij za izdelke, ki so podobni izdelkom, omenjenim v okviru te publikacije skupinske varnosti, skladno z načeli vodil IEC 104 in ISO/IEC 51.
Ena od dolžnosti tehničnega odbora je, da med pripravo publikacij uporablja osnovne varnostne publikacije in/ali publikacije skupinske varnosti, kadar je to primerno.
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
01-maj-2025
Nadomešča:
SIST EN 61558-2-20:2011
Varnost transformatorjev, dušilk, napajalnikov in podobnih izdelkov - 2-20. del:
Posebne zahteve in preskusi za majhne reaktorje
Safety of transformers, reactors, power supply units and combinations thereof - Part 2-
20: Particular requirements and tests for small reactors
Sicherheit von Transformatoren, Drosseln, Netzgeräten und entsprechende
Kombinationen - Teil 2-20: Besondere Anforderungen und Prüfungen an Kleindrosseln
Sécurité des transformateurs, bobines d'inductance, blocs d'alimentation et des
combinaisons de ces éléments - Partie 2-20: Règles particulières et essais pour les
petites bobines d'inductance
Ta slovenski standard je istoveten z: EN IEC 61558-2-20:2025
ICS:
29.180 Transformatorji. Dušilke Transformers. Reactors
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
EUROPEAN STANDARD EN IEC 61558-2-20
NORME EUROPÉENNE
EUROPÄISCHE NORM March 2025
ICS 29.180 Supersedes EN 61558-2-20:2011
English Version
Safety of transformers, reactors, power supply units and
combinations thereof - Part 2-20: Particular requirements and
tests for small reactors
(IEC 61558-2-20:2022)
Sécurité des transformateurs, bobines d'inductance, blocs Sicherheit von Transformatoren, Drosseln, Netzgeräten und
d'alimentation et des combinaisons de ces éléments - entsprechende Kombinationen - Teil 2-20: Besondere
Partie 2-20 : Exigences particulières et essais pour les Anforderungen und Prüfungen an Kleindrosseln
petites bobines d'inductance (IEC 61558-2-20:2022)
(IEC 61558-2-20:2022)
This European Standard was approved by CENELEC on 2024-10-16. 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 61558-2-20:2025 E
European foreword
The text of document 96/556/FDIS, future edition 3 of IEC 61558-2-20, prepared by TC 96
"Transformers, reactors, power supply units, and combinations thereof" was submitted to the IEC-
CENELEC parallel vote and approved by CENELEC as EN IEC 61558-2-20:2025.
The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2026-03-31
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2028-03-31
document have to be withdrawn
This document supersedes EN 61558-2-20:2011 and all of its amendments and corrigenda (if any).
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 61558-1:2019.
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 61558-2-20:2022 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 60204-1:2016 NOTE Approved as EN 60204-1:2018
IEC 60204-1:2016/AMD1:2021 NOTE Approved as EN 60204-1:2018/A1:— (not modified)
IEC 60938-1:2021 NOTE Approved as EN IEC 60938-1:2021 (not modified)
IEC 60938-2:2021 NOTE Approved as EN IEC 60938-2:2021 (not modified)
IEC 61347-2-8:2000 NOTE Approved as EN 61347-2-8:2001 (not modified)
IEC 61347-2-8:2000/A1:2006 NOTE Approved as EN 61347-2-8:2001/A1:2006 (not modified)
IEC 61347-2-9:2012 NOTE Approved as EN 61347-2-9:2013 (not modified)
IEC 61558 series NOTE Approved as EN 61558 series
IEC 61558-2-13:2009 NOTE Approved as EN 61558-2-13:2009 (not modified)
Under preparation. Stage at the time of publication: EN 60204-1:2018/prA1:2020.
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.
Annex ZA of EN IEC 61558-1:2019 is applicable, except as follows:
Add:
Publication Year Title EN/HD Year
IEC 60076-6 2007 Power transformers - Part 6: Reactors EN 60076-6 2008
IEC 61558-1 2017 Safety of transformers, reactors, power EN IEC 61558-1 2019
supply units and combinations thereof -
Part 1: General requirements and tests
IEC 61558-2-16 2021 Safety of transformers, reactors, power EN IEC 61558-2-16 2025
supply units and combinations thereof -
Part 2-16: Particular requirements and
tests for switch mode power supply units
and transformers for switch mode power
supply units for general applications
IEC 61558-2-20 ®
Edition 3.0 2022-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
GROUP SAFETY PUBLICATION
PUBLICATION GROUPÉE DE SÉCURITÉ
Safety of transformers, reactors, power supply units and combinations thereof –
Part 2-20: Particular requirements and tests for small reactors
Sécurité des transformateurs, bobines d'inductance, blocs d'alimentation et
combinaisons de ces éléments –
Partie 2-20: Exigences particulières et essais pour les petites bobines
d'inductance
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.180 ISBN 978-2-8322-6118-7
– 2 – IEC 61558-2-20:2022 © IEC 2022
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 7
3 Terms and definitions . 7
4 General requirements . 9
5 General notes on tests . 9
6 Ratings . 10
7 Classification . 10
8 Marking and other information . 11
9 Protection against electric shock . 13
10 Change of voltage setting . 13
11 Voltage drop . 14
12 No-load output voltage . 14
13 Short-circuit voltage . 14
14 Heating . 14
15 Short-circuit and overload protection . 15
16 Mechanical strength . 16
17 Protection against harmful ingress of dust, solid objects and moisture . 16
18 Insulation resistance, dielectric strength and leakage current . 16
19 Construction . 16
20 Components . 17
21 Internal wiring . 17
22 Supply connection and other external flexible cable or cords . 17
23 Terminals for external conductors . 18
24 Provisions for protective earthing. 18
25 Screws and connections . 18
26 Creepage distances, clearances and distances through insulation . 18
27 Resistance to heat, fire and tracking . 18
28 Resistance to rusting . 18
Annexes . 19
Annex AA (informative) Characteristic parameter measurements . 19
Annex BB (normative) Particular requirements for associated reactors with
frequencies > 500 Hz . 19
Annex CC (normative) Partial discharge (PD) test . 21
Bibliography . 22
Table 101 – Symbols indicating the kind of transformer . 13
IEC 61558-2-20:2022 © IEC 2022 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SAFETY OF TRANSFORMERS, REACTORS,
POWER SUPPLY UNITS AND COMBINATIONS THEREOF –
Part 2-20: Particular requirements and tests for small reactors
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 61558-2-20 has been prepared by IEC technical committee 96: Transformers, reactors,
power supply units and combinations thereof. It is an International Standard.
This third edition cancels and replaces the second edition published in 2010. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) Adjustment of structure and references in accordance with IEC 61558-1:2017.
b) Additional Annex AA with references for characteristic parameter measurements.
c) Additional Annex BB for associated reactors with frequencies above 500 Hz.
d) Additional Annex CC for partial discharge.
– 4 – IEC 61558-2-20:2022 © IEC 2022
The text of this International Standard is based on the following documents:
Draft Report on voting
96/556/FDIS 96/564/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.
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/publications.
It has the status of a group safety publication in accordance with IEC Guide 104.
This International Standard is to be used in conjunction with IEC 61558-1:2017.
This document supplements or modifies the corresponding clauses in IEC 61558-1:2017, so as
to convert that publication into the IEC standard: Particular requirements and tests for small
reactors.
A list of all parts in the IEC 61558 series published under the general title Safety of transformers,
reactors, power supply units and combinations thereof, can be found on the IEC website.
Future standards in this series will carry the new general title as cited above. Titles of existing
standards in this series will be updated at the time of the next edition.
Where this document states "addition", "modification" or "replacement", the relevant text of
IEC 61558-1:2017 is to be adopted accordingly.
In this document, the following print types are used:
– requirements proper: in roman type;
– test specifications: in italic type;
– explanatory matter: in smaller roman type.
In the text of this document, the words in bold are defined in Clause 3.
Subclauses, notes, figures and tables additional to those in IEC 61558-1:2017 are numbered
starting from 101; supplementary annexes are entitled AA, BB, etc.
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.
IEC 61558-2-20:2022 © IEC 2022 – 5 –
INTRODUCTION
IEC TC 96 has a group safety function in accordance with IEC Guide 104 for transformers other
than those intended to supply distribution networks, in particular transformers and power supply
units intended to allow the application of protective measures against electric shock as defined
by TC 64, but in certain cases including the limitation of voltage and horizontal safety function
for SELV, in accordance with IEC 60364-4-41.
The group safety function (GSF) is used because of responsibility for safety extra-low voltage
(SELV) in accordance with IEC 61140:2016, 5.2.6 and IEC 60364-4-41:2005, 414.3.1 or control
circuits in accordance with IEC 60204-1:2016, 7.2.4.
The group safety function is used for each part of IEC 61558-2 because different standards of
the IEC 61558 series can be combined in one construction but in certain cases with no limitation
of rated output power.
For example an auto-transformer in accordance with IEC 61558-2-13 can be designed with a
separate SELV-circuit in accordance with the particular requirements for IEC 61558-2-6 relating
to the general requirements of IEC 61558-1.
– 6 – IEC 61558-2-20:2022 © IEC 2022
SAFETY OF TRANSFORMERS, REACTORS,
POWER SUPPLY UNITS AND COMBINATIONS THEREOF –
Part 2-20: Particular requirements and tests for small reactors
1 Scope
Replacement
This part of IEC 61558 deals with the safety of small reactors for general applications. Small
reactors incorporating electronic circuits are also covered by this document.
NOTE 1 Safety includes electrical, thermal and mechanical aspects.
Unless otherwise specified, from here onward, the term transformer or reactor covers small
reactors.
This document is applicable to stationary or portable, single-phase or polyphase, air-cooled
(natural or forced) general purpose reactors including alternating current, premagnetised and
current compensated independent or associated dry-type reactors. The windings can be
encapsulated or non-encapsulated.
The rated supply voltage does not exceed 1 000 V AC or 1 500 V ripple-free DC, the rated
supply frequency and the internal operating frequencies do not exceed 100 MHz.
This document can be used for reactors with a fundamental frequency above 500 Hz (see
Annex BB).
The rated power does not exceed:
– 25 kVAR AC (25 kW DC) for single-phase reactors,
– 50 kVAR AC (50 kW DC) for poly-phase reactors.
This document is applicable to reactors without limitation of the rated power subject to an
agreement between the purchaser and the manufacturer.
This document does not apply to:
– reactors covered by IEC 60076-6 for rated voltages above 1 000 V;
– ballast for tubular fluorescent covered by IEC 61347-2-8;
– ballast for discharge lamps (excluding tubular fluorescent lamps) covered by IEC 61347‑2‑9.
– fixed inductors for electromagnetic interference suppression covered by IEC 60938 series
NOTE 2 For reactors filled with liquid dielectric or pulverised material such as sand, additional requirements are
under consideration.
NOTE 3 Normally, reactors are intended to be associated with equipment for functional requirements of the
equipment or requirements by the installation rules or by other appliance specifications. The protection against
electric shock may be provided or completed by other parts or features of the equipment, such as the body.
NOTE 4 Reactors for particular applications will in the future be covered by complementary normative annexes.
Attention is drawn to the following if necessary:
– for reactors intended to be used in vehicles, on board ships, and aircraft, additional
requirements (from other applicable standards, national rules, etc.);
IEC 61558-2-20:2022 © IEC 2022 – 7 –
– measures to protect the enclosure and the components inside the enclosure against
external influences such as fungus, vermin, termites, solar-radiation, and icing;
– the different conditions for transportation, storage, and operation of the reactors;
– additional requirements in accordance with other appropriate standards and national rules
may be applicable to reactors intended for use in special environments.
Future technological development of reactors may necessitate a need to increase the upper
limit of the frequencies. Until then, this document may be used as a guidance document.
This group safety publication focusing on safety guidance is primarily intended to be used as a
product safety standard for the products mentioned in the scope, but is also intended to be used
by technical committees in the preparation of publications for products similar to those
mentioned in the scope of this group safety publication, in accordance with the principles laid
down in IEC Guide 104 and lSO/lEC Guide 51.
One of the responsibilities of a technical committee is, wherever applicable, to make use of
basic safety publications and/or group safety publications in the preparation of its publications.
2 Normative references
This clause of IEC 61558-1:2017 is applicable, except as follows:
Addition
IEC 60076-6:2007, Power transformers – Part 6: Reactors
IEC 61558-1:2017, Safety of transformers, reactors, power supply units and combinations
thereof – Part 1: General requirements and tests
IEC 61558-2-16:2021, Safety of transformers, reactors, power supply units and combinations
thereof – Part 16: Particular requirements and tests for switch mode power supply units and
transformers for switch mode power supply units for general applications
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 61558-1:2017 apply.
ISO and IEC maintain terminology databases for use in standardization at the following
addresses:
• IEC Electroped
...
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