SIST EN IEC 60947-4-1:2025
(Main)Low-voltage switchgear and controlgear - Part 4-1: Contactors and motor-starters - Electromechanical contactors and motor-starters (IEC 60947-4-1:2023)
Low-voltage switchgear and controlgear - Part 4-1: Contactors and motor-starters - Electromechanical contactors and motor-starters (IEC 60947-4-1:2023)
IEC 60947-4-1:2023 is applicable to the following equipment:
- electromechanical contactors and starters including motor protective switching devices (MPSD and IMPSD);
- actuators of contactor relays;
- contacts dedicated exclusively to the coil circuit of the contactor or the contactor relay;
- dedicated accessories (e.g. dedicated wiring, dedicated latch accessory);
intended to be connected to distribution circuits, motors circuits and other load circuits, the rated voltage of which does not exceed 1 000 V AC or 1 500 V DC.
This fifth edition cancels and replaces the fourth edition published in 2018. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition:
a) objective in the scope;
b) instantaneous only motor protective switching device IMPSD (3.5.33);
c) kinds of equipment (5.2.1);
d) methods of overload protection of motors (5.2.6);
e) adoption of the AC-7d from IEC 61095:2023 (in 5.4.2);
f) separately mounted overload relay of a starter (in 5.7.3 b));
g) starter and contactor suitable for use downstream to basic drive module (6.1.2 w));
h) reference to IEC TS 63058 for environmental aspects (in 6.4);
i) wiring subject to movement (in 8.1.3);
j) use of voltage transient limiting device (8.1.18);
k) accessible parts subject to temperature limits (in 8.2.2.3);
l) reference to Annex X of IEC 60947-1:2020 for the co-ordination of MPSD with SCPD (8.2.5.4);
m) reference to IEC TR 63216 with different EMC environments (8.3.1);
n) reference to IEC TR 63201 for the embedded software design (8.4);
o) reference to IEC TS 63208 for cybersecurity aspects (8.5);
p) update and completion of the measurement method of the power consumption of the electromagnet (9.3.3.2.1.2);
q) update of Annex C including rational about AC-3e;
r) determination of the critical load current for photovoltaic applications (M.8.7).
Niederspannungsschaltgeräte - Teil 4-1: Schütze und Motorstarter - Elektromechanische Schütze und Motorstarter (IEC 60947-4-1:2023)
Appareillage à basse tension - Partie 4-1: Contacteurs et démarreurs de moteurs Contacteurs et démarreurs électromécaniques (IEC 60947-4-1:2023)
L'IEC 60947-4-1:2023 s'applique aux équipements suivants:
- contacteurs électromécaniques et démarreurs, y compris les appareils de connexion de protection des moteurs (ACPM et ACPIM);
- organes de commande de contacteurs auxiliaires;
- contacts destinés exclusivement au circuit de la bobine du contacteur ou du contacteur auxiliaire;
- accessoires dédiés (câblage dédié, accessoires d'accrochage dédié, par exemple);
destinés à être connectés à des circuits de distribution, des circuits de moteur et à d'autres circuits de charge, dont la tension assignée ne dépasse pas 1 000 V en courant alternatif ou 1 500 V en courant continu.
Cette cinquième édition annule et remplace la quatrième édition parue en 2018. Cette édition constitue une révision technique.
Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
a) objet du domaine d'application;
b) appareil de connexion de protection uniquement instantanée des moteurs (ACPIM) (3.5.33);
c) nature du matériel (5.2.1);
d) méthodes de protection des moteurs contre les surcharges (5.2.6);
e) adoption de la catégorie AC-7d de l'IEC 61095:2023 (en 5.4.2);
f) relais de surcharge monté séparément d'un démarreur (en 5.7.3 b));
g) démarreur et contacteur adaptés à une utilisation en aval d'un module d'entraînement principal (6.1.2 w));
h) référence à l'IEC TS 63058 pour les aspects relatifs à l'environnement (en 6.4);
i) câblage soumis à un mouvement (en 8.1.3);
j) utilisation d'un dispositif de limitation des transitoires de tension (8.1.18);
k) parties accessibles soumises à des limites de température (en 8.2.2.3);
l) référence à l'Annexe X de l'IEC 60947-1:2020 pour la coordination entre ACPM et DPCC (8.2.5.4);
m) référence à l'IEC TR 63216 avec différents environnements de CEM (8.3.1);
n) référence à l'IEC TR 63201 pour la conception des logiciels intégrés (8.4);
o) référence à l'IEC TS 63208 pour les aspects relatifs à la cybersécurité (8.5);
p) mise à jour et complément de la méthode de mesure de la consommation de puissance de l'électroaimant (9.3.3.2.1.2);
q) mise à jour de l'Annexe C, y compris justification de la catégorie AC-3e;
r) détermination du courant critique de charge pour les applications photovoltaïques (M.8.7).
La version française de cette norme n'a pas été soumise au vote.
Nizkonapetostne stikalne in krmilne naprave - 4-1. del: Kontaktorji in motorski zaganjalniki - Elektromehanski kontaktorji in motorski zaganjalniki (IEC 60947-4-1:2023)
Ta del standarda IEC 60947 se uporablja za naslednjo opremo:
– elektromehanske kontaktorje in zaganjalnike, vključno z motorsko zaščitno stikalno napravo (MPSD in IMPSD);
– sprožilnike kontaktorskih relejev;
– kontakte, ki so namenjeni izključno tokokrogu tuljave kontaktorja ali kontaktorskega releja;
– namenski pribor (npr. namensko ožičenje, namenski zapah);
namenjeno za priključitev v razdelilne tokokroge, motorna vezja in druge obremenitvene tokokroge, katerih nazivna napetost ne presega 1000 V AC oziroma 1500 V DC.
Ta dokument se ne uporablja za:
– zaganjalnike za motorje na enosmerni tok;
– pomožne kontakte kontaktorjev in kontakte kontaktorskih relejev. Ti so zajeti v standardu IEC 60947-5-1;
– napravo za zaščito pred kratkim stikom, vgrajeno v zaganjalnikih, ki niso motorske zaščitne stikalne naprave. To je zajeto v standardih IEC 60947-2 in IEC 60947-3;
– funkcijo zaščite motorja pred preobremenitvijo, ki jo izvajajo krmilne enote za vgrajeno toplotno zaščito (PTC). Te so zajete v standardu IEC 60947-8;
– uporabo opreme z uvedbo dodatnih ukrepov v eksplozivnih okoljih. Ti so podani v skupini standardov IEC 60079.
Namen tega dokumenta je navesti:
• značilnosti in sestavo opreme (točka 5);
• pogoje, ki veljajo za opremo in se navezujejo na:
– njeno delovanje (5.2.5) in zaščitne funkcije (5.2.6, 5.7, 5.8);
– njena predvidena okolja (6.5, 8.3.1) in uporabo (5.4, dodatek C, dodatek D, dodatek G, dodatek H, dodatek I, dodatek M, dodatek O), vključno z varnostno uporabo (dodatek F, dodatek K, dodatek L);
– njeno konstrukcijo in delovanje (točka 8), vključno z zahtevami za zmanjšanje tveganja električnega udara, toplotne nevarnosti, energetske nevarnosti, nevarnosti požara in mehanske nevarnosti, razumno predvidljive zlorabe, težav z elektromagnetno združljivostjo (EMC), napak programske opreme in varnostnih težav;
• preskuse, s katerimi se potrjuje izpolnjevanje teh pogojev, in metode, ki jih je treba uporabiti za te preskuse (točka 9);
• informacije, ki jih je treba vključiti v opremo ali v dokumentacijo izdelka (točka 6).
General Information
Relations
Overview - EN IEC 60947-4-1:2025 (Low-voltage switchgear | Contactors & Motor-starters)
EN IEC 60947-4-1:2025 is the fifth-edition European adoption of IEC 60947-4-1:2023. It defines requirements, tests and product information for electromechanical contactors and motor-starters, including motor protective switching devices (MPSD and IMPSD), actuators, coil‑circuit contacts and dedicated accessories for low‑voltage distribution and motor circuits (rated voltages up to 1 000 V AC or 1 500 V DC). This edition replaces the 2018/2020/2021 versions and constitutes a technical revision aligned with modern design, testing, EMC, environmental and cybersecurity considerations.
Key topics and technical requirements
- Scope and equipment types: Electromechanical contactors, starters, separately mounted overload relays, IMPSD (instantaneous-only motor protective switching device), actuators and dedicated accessories intended for low‑voltage applications.
- Rated values and duties: Specified rated voltages, currents, frequency, utilization categories and short‑circuit characteristics for reliable motor switching and protection.
- Overload protection methods: Updated methods for motor overload protection and coordination with short‑circuit protective devices (SCPD).
- Utilization categories: Adoption of new categories including AC‑7d (per IEC 61095:2023) for specific switching duties.
- EMC and electromagnetic considerations: References to IEC TR 63216 for EMC environments and requirements for wiring subject to movement and transient limiting devices.
- Environmental & lifecycle information: Reference to IEC TS 63058 for environmental aspects; instructions for installation, maintenance, decommissioning and reuse/repair.
- Software and cybersecurity: Guidance and references for embedded software design (IEC TR 63201) and cybersecurity aspects (IEC TS 63208).
- Measurement & testing updates: Revised measurement method for electromagnet power consumption and updated annexes (e.g., AC‑3e rationale, PV critical load current determination).
Practical applications and users
This standard is essential for:
- Manufacturers of low‑voltage switchgear, electromechanical contactors and motor‑starters - for design, type testing and declaration of conformity.
- Panel builders and OEMs specifying contactors and starters for industrial machinery, HVAC, pumps and motor drives.
- Electrical engineers and specifiers evaluating overload protection, coordination with SCPDs and utilization categories for motor control.
- Test laboratories and certification bodies performing compliance testing, EMC assessment and power‑consumption measurements.
- Renewable energy and PV system designers using the standard’s guidance for critical load current and DC switching considerations.
Related standards
- EN IEC 60947‑1:2021 (General rules)
- IEC 61095 / EN IEC 61095 (AC‑7d adoption)
- IEC TR 63216 (EMC assessment)
- IEC TR 63201 (Embedded software)
- IEC TS 63058 (Environmental aspects)
- IEC 60947 series (other parts on circuit‑breakers, assemblies, etc.)
Keywords: EN IEC 60947-4-1:2025, low-voltage switchgear, contactors, motor-starters, electromechanical contactors, MPSD, IMPSD, overload protection, EMC, cybersecurity.
Frequently Asked Questions
SIST EN IEC 60947-4-1:2025 is a standard published by the Slovenian Institute for Standardization (SIST). Its full title is "Low-voltage switchgear and controlgear - Part 4-1: Contactors and motor-starters - Electromechanical contactors and motor-starters (IEC 60947-4-1:2023)". This standard covers: IEC 60947-4-1:2023 is applicable to the following equipment: - electromechanical contactors and starters including motor protective switching devices (MPSD and IMPSD); - actuators of contactor relays; - contacts dedicated exclusively to the coil circuit of the contactor or the contactor relay; - dedicated accessories (e.g. dedicated wiring, dedicated latch accessory); intended to be connected to distribution circuits, motors circuits and other load circuits, the rated voltage of which does not exceed 1 000 V AC or 1 500 V DC. This fifth edition cancels and replaces the fourth edition published in 2018. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition: a) objective in the scope; b) instantaneous only motor protective switching device IMPSD (3.5.33); c) kinds of equipment (5.2.1); d) methods of overload protection of motors (5.2.6); e) adoption of the AC-7d from IEC 61095:2023 (in 5.4.2); f) separately mounted overload relay of a starter (in 5.7.3 b)); g) starter and contactor suitable for use downstream to basic drive module (6.1.2 w)); h) reference to IEC TS 63058 for environmental aspects (in 6.4); i) wiring subject to movement (in 8.1.3); j) use of voltage transient limiting device (8.1.18); k) accessible parts subject to temperature limits (in 8.2.2.3); l) reference to Annex X of IEC 60947-1:2020 for the co-ordination of MPSD with SCPD (8.2.5.4); m) reference to IEC TR 63216 with different EMC environments (8.3.1); n) reference to IEC TR 63201 for the embedded software design (8.4); o) reference to IEC TS 63208 for cybersecurity aspects (8.5); p) update and completion of the measurement method of the power consumption of the electromagnet (9.3.3.2.1.2); q) update of Annex C including rational about AC-3e; r) determination of the critical load current for photovoltaic applications (M.8.7).
IEC 60947-4-1:2023 is applicable to the following equipment: - electromechanical contactors and starters including motor protective switching devices (MPSD and IMPSD); - actuators of contactor relays; - contacts dedicated exclusively to the coil circuit of the contactor or the contactor relay; - dedicated accessories (e.g. dedicated wiring, dedicated latch accessory); intended to be connected to distribution circuits, motors circuits and other load circuits, the rated voltage of which does not exceed 1 000 V AC or 1 500 V DC. This fifth edition cancels and replaces the fourth edition published in 2018. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition: a) objective in the scope; b) instantaneous only motor protective switching device IMPSD (3.5.33); c) kinds of equipment (5.2.1); d) methods of overload protection of motors (5.2.6); e) adoption of the AC-7d from IEC 61095:2023 (in 5.4.2); f) separately mounted overload relay of a starter (in 5.7.3 b)); g) starter and contactor suitable for use downstream to basic drive module (6.1.2 w)); h) reference to IEC TS 63058 for environmental aspects (in 6.4); i) wiring subject to movement (in 8.1.3); j) use of voltage transient limiting device (8.1.18); k) accessible parts subject to temperature limits (in 8.2.2.3); l) reference to Annex X of IEC 60947-1:2020 for the co-ordination of MPSD with SCPD (8.2.5.4); m) reference to IEC TR 63216 with different EMC environments (8.3.1); n) reference to IEC TR 63201 for the embedded software design (8.4); o) reference to IEC TS 63208 for cybersecurity aspects (8.5); p) update and completion of the measurement method of the power consumption of the electromagnet (9.3.3.2.1.2); q) update of Annex C including rational about AC-3e; r) determination of the critical load current for photovoltaic applications (M.8.7).
SIST EN IEC 60947-4-1:2025 is classified under the following ICS (International Classification for Standards) categories: 29.120.99 - Other electrical accessories; 29.130.20 - Low voltage switchgear and controlgear. The ICS classification helps identify the subject area and facilitates finding related standards.
SIST EN IEC 60947-4-1:2025 has the following relationships with other standards: It is inter standard links to SIST EN IEC 60947-4-1:2019/AC:2020, SIST EN IEC 60947-4-1:2019/AC:2021, SIST EN IEC 60947-4-1:2019. Understanding these relationships helps ensure you are using the most current and applicable version of the standard.
SIST EN IEC 60947-4-1:2025 is associated with the following European legislation: EU Directives/Regulations: 2014/30/EU, 2014/35/EU; Standardization Mandates: M/511, M/552. When a standard is cited in the Official Journal of the European Union, products manufactured in conformity with it benefit from a presumption of conformity with the essential requirements of the corresponding EU directive or regulation.
You can purchase SIST EN IEC 60947-4-1:2025 directly from iTeh Standards. The document is available in PDF format and is delivered instantly after payment. Add the standard to your cart and complete the secure checkout process. iTeh Standards is an authorized distributor of SIST standards.
Standards Content (Sample)
SLOVENSKI STANDARD
01-november-2025
Nadomešča:
SIST EN IEC 60947-4-1:2019
SIST EN IEC 60947-4-1:2019/AC:2020
SIST EN IEC 60947-4-1:2019/AC:2021
Nizkonapetostne stikalne in krmilne naprave - 4-1. del: Kontaktorji in motorski
zaganjalniki - Elektromehanski kontaktorji in motorski zaganjalniki (IEC 60947-4-
1:2023)
Low-voltage switchgear and controlgear - Part 4-1: Contactors and motor-starters -
Electromechanical contactors and motor-starters (IEC 60947-4-1:2023)
Niederspannungsschaltgeräte - Teil 4-1: Schütze und Motorstarter - Elektromechanische
Schütze und Motorstarter (IEC 60947-4-1:2023)
Appareillage à basse tension - Partie 4-1: Contacteurs et démarreurs de moteurs
Contacteurs et démarreurs électromécaniques (IEC 60947-4-1:2023)
Ta slovenski standard je istoveten z: EN IEC 60947-4-1:2025
ICS:
29.130.20 Nizkonapetostne stikalne in Low voltage switchgear and
krmilne naprave controlgear
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
EUROPEAN STANDARD EN IEC 60947-4-1
NORME EUROPÉENNE
EUROPÄISCHE NORM September 2025
ICS 29.120.99; 29.130.20 Supersedes EN IEC 60947-4-1:2019; EN IEC 60947-4-
1:2019/AC:2020-05; EN IEC 60947-4-1:2019/AC:2021-04
English Version
Low-voltage switchgear and controlgear - Part 4-1: Contactors
and motor-starters - Electromechanical contactors and motor-
starters
(IEC 60947-4-1:2023)
Appareillage à basse tension - Partie 4-1: Contacteurs et Niederspannungsschaltgeräte - Teil 4-1: Schütze und
démarreurs de moteurs - Contacteurs et démarreurs Motorstarter - Elektromechanische Schütze und
électromécaniques Motorstarter
(IEC 60947-4-1:2023) (IEC 60947-4-1:2023)
This European Standard was approved by CENELEC on 2023-12-13. 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 60947-4-1:2025 E
European foreword
The text of document 121A/571/FDIS, future edition 5 of IEC 60947-4-1, prepared by SC 121A "Low-
voltage switchgear and controlgear" of IEC/TC 121 "Switchgear and controlgear and their assemblies
for low voltage" 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) 2026-09-30
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2028-09-30
document have to be withdrawn
This document supersedes EN IEC 60947-4-1:2019 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 60947-1:2021.
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 60947-4-1:2023 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 60068-2-2:2007 NOTE Approved as EN 60068-2-2:2007 (not modified)
IEC 60072-1:2022 NOTE Approved as EN IEC 60072-1:2022 (not modified)
IEC 60079 series NOTE Approved as EN IEC 60079 series
IEC 60079-7 NOTE Approved as EN 60079-7
IEC 60079-29-3:2014 NOTE Approved as EN 60079-29-3:2014 (not modified)
IEC 60204-1 NOTE Approved as EN 60204-1
IEC 60269-1:2006 NOTE Approved as EN 60269-1:2007 (not modified)
IEC 60269-2:2013 NOTE Approved as HD 60269-2:2013
IEC 60384-17:2019 NOTE Approved as EN IEC 60384-17:2019 (not modified)
IEC 60664-1:2020 NOTE Approved as EN IEC 60664-1:2020 (not modified)
IEC 60721-3-3 NOTE Approved as EN IEC 60721-3-3
IEC 60812:2018 NOTE Approved as EN IEC 60812:2018 (not modified)
IEC 60947-3:2020 NOTE Approved as EN IEC 60947-3:2021 (not modified)
IEC 60947-4-2 NOTE Approved as EN IEC 60947-4-2
IEC 60947-6-2 NOTE Approved as EN IEC 60947-6-2
IEC 60947-8 NOTE Approved as EN IEC 60947-8
IEC 60990:2016 NOTE Approved as EN 60990:2016 (not modified)
IEC 61000-6-5 NOTE Approved as EN 61000-6-5
IEC 61032 NOTE Approved as EN 61032
IEC 61508-2 NOTE Approved as EN 61508-2
IEC 61508-3 NOTE Approved as EN 61508-3
IEC 61508-4:2010 NOTE Approved as EN 61508-4:2010 (not modified)
IEC 61508-6:2010 NOTE Approved as EN 61508-6:2010 (not modified)
IEC 61557-12:2018 NOTE Approved as EN IEC 61557-12:2022 (not modified)
IEC 61557-12:2018/A1:2021 NOTE Approved as EN IEC 61557-12:2022/A1:2022 (not modified)
IEC 61649 NOTE Approved as EN 61649
IEC 61915-2:2011 NOTE Approved as EN 61915-2:2012 (not modified)
IEC 62061 NOTE Approved as EN IEC 62061
IEC 62443 series NOTE Approved as EN IEC 62443 series
IEC 62477-1:2022 NOTE Approved as EN IEC 62477-1:2023 (not modified)
IEC 62683-1 NOTE Approved as EN 62683-1
IEC 63365 NOTE Approved as EN IEC 63365
IEC 63404 NOTE Approved as EN IEC 63404
ISO/IEC 80079-34 NOTE Approved as EN ISO/IEC 80079-34
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
IEC 60034-1 2022 Rotating electrical machines - Part 1: - -
Rating and performance
IEC 60034-12 2016 Rotating electrical machines - Part 12: EN 60034-12 2017
Starting performance of single-speed
three-phase cage induction motors
IEC 60034-30-1 2014 Rotating electrical machines - Part 30-1: EN 60034-30-1 2014
Efficiency classes of line operated AC
motors (IE code)
IEC 60068-2-14 2023 Environmental testing - Part 2-14: Tests - EN IEC 60068-2-14 2023
Test N: Change of temperature
IEC 60079-14 - Explosive atmospheres - Part 14: Electrical EN IEC 60079-14 -
installation design, selection and
installation of equipment, including initial
inspection
IEC 60085 2007 Electrical insulation - Thermal evaluation EN 60085 2008
and designation
IEC 60364-1 (mod) 2005 Low-voltage electrical installations - Part 1: HD 60364-1 2008
Fundamental principles, assessment of
general characteristics, definitions
- - + A11 2017
IEC 60715 2017 Dimensions of low-voltage switchgear and EN 60715 2017
controlgear - Standardized mounting on
rails for mechanical support of switchgear,
controlgear and accessories
IEC 60730-1 - Automatic electrical controls - Part 1: EN IEC 60730-1 -
General requirements
IEC 60947-1 2020 Low-voltage switchgear and controlgear - EN IEC 60947-1 2021
Part 1: General rules
IEC 60947-2 2016 Low-voltage switchgear and controlgear - EN 60947-2 2017
Part 2: Circuit-breakers
Publication Year Title EN/HD Year
IEC 60947-5-1 2016 Low-voltage switchgear and controlgear - EN 60947-5-1 2017
Part 5-1: Control circuit devices and
switching elements - Electromechanical
control circuit devices
IEC 61051-2 - Varistors for use in electronic equipment - EN IEC 61051-2 -
Part 2: Sectional specification for surge
suppression varistors
IEC 61095 2023 Electromechanical contactors for EN IEC 61095 2025
household and similar purposes
IEC 61140 2016 Protection against electric shock - EN 61140 2016
Common aspects for installation and
equipment
IEC 61439 series Low-voltage switchgear and controlgear EN IEC 61439 series
assemblies
IEC 61643-331 - Components for low-voltage surge EN IEC 61643-331 -
protection - Part 331: Performance
requirements and test methods for metal
oxide varistors (MOV)
IEC 61800-5-1 2022 Adjustable speed electrical power drive EN IEC 61800-5-1 2023
systems - Part 5-1: Safety requirements -
Electrical, thermal and energy
IEC 61810-1 - Electromechanical elementary relays - Part EN 61810-1 -
1: General and safety requirements
IEC/TS 63058 - Switchgear and controlgear and their - -
assemblies for low voltage - Environmental
aspects
IEC/TS 63208 - Low-voltage switchgear and controlgear - - -
Security aspects
IEC/TR 63216 2019 Low-voltage switchgear and controlgear - CLC IEC/TR 63216 2020
Electromagnetic compatibility assessment
for switchgear and controlgear and their
assemblies
CISPR 11 (mod) 2015 Industrial, scientific and medical equipment EN 55011 2016
- Radio-frequency disturbance
characteristics - Limits and methods of
measurement
+ A1 2016 + A1 2017
- - + A11 2020
+ A2 2019 + A2 2021
ISO 2859-1 - Sampling procedures for inspection by - -
attributes - Part 1: Sampling schemes
indexed by acceptance quality limit (AQL)
for lot-by-lot inspection
ISO 3864-2 - Graphical symbols - Safety colours and - -
safety signs - Part 2: Design principles for
product safety labels
IEC 60947-4-1 ®
Edition 5.0 2023-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Low-voltage switchgear and controlgear –
Part 4-1: Contactors and motor-starters – Electromechanical contactors and
motor-starters
Appareillage à basse tension –
Partie 4-1: Contacteurs et démarreurs de moteurs – Contacteurs et démarreurs
électromécaniques
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.120.99, 29.130.20 ISBN 978-2-8322-7773-7
– 2 – IEC 60947-4-1:2023 © IEC 2023
CONTENTS
FOREWORD . 10
1 Scope . 13
2 Normative references . 14
3 Terms, definitions, symbols and abbreviated terms . 15
3.1 General . 15
3.2 Alphabetical index of terms . 15
3.3 Terms and definitions concerning contactors . 18
3.4 Terms and definitions of the functions of starters . 19
3.5 Terms and definitions concerning starters . 20
3.6 Terms and definitions concerning characteristic quantities . 26
3.7 Terms and definitions concerning safety aspects . 28
3.8 Terms and definitions concerning electric motor characteristics . 31
3.9 Symbols and abbreviated terms . 31
4 Classification . 32
5 Characteristics of contactors and starters . 33
5.1 Summary of characteristics . 33
5.2 Type of equipment . 33
5.2.1 Kind of equipment . 33
5.2.2 Number of poles . 34
5.2.3 Kind of current (AC or DC) . 34
5.2.4 Interrupting medium (air, oil, gas, vacuum, etc.) . 34
5.2.5 Operating conditions of the equipment . 34
5.2.6 Methods of overload protection of motors . 34
5.3 Rated and limiting values for main circuits . 35
5.3.1 Rated voltages . 35
5.3.2 Currents or powers . 36
5.3.3 Rated frequency . 38
5.3.4 Rated duties . 38
5.3.5 Normal load and overload characteristics . 39
5.3.6 Short-circuit characteristics . 41
5.3.7 Pole impedance of a contactor (Z) or starter . 41
5.4 Utilization category . 41
5.4.1 General . 41
5.4.2 Assignment of utilization categories based on the results of tests . 42
5.5 Control circuits . 43
5.6 Auxiliary circuits . 44
5.7 Characteristics of relay and release of overload relays and of motor
protective switching device (MPSD) . 44
5.7.1 Summary of characteristics . 44
5.7.2 Types of relay or release . 44
5.7.3 Characteristic values . 45
5.7.4 Designation and current settings of overload relays . 46
5.7.5 Time-current characteristics of overload relays . 47
5.7.6 Influence of ambient air temperature. 47
5.8 Co-ordination with short-circuit protective devices . 47
5.9 Void . 47
IEC 60947-4-1:2023 © IEC 2023 – 3 –
5.10 Types and characteristics of automatic change-over devices and automatic
acceleration control devices . 47
5.10.1 Types . 47
5.10.2 Characteristics. 47
5.11 Types and characteristics of auto-transformers for two-step auto-transformer
starters . 48
5.12 Types and characteristics of starting resistors for rheostatic rotor starters . 48
6 Product information . 49
6.1 Nature of information . 49
6.1.1 Identification . 49
6.1.2 Characteristics, basic rated values and utilization . 49
6.2 Marking . 51
6.3 Instructions for installation, operation, maintenance, decommissioning and
dismantling . 52
6.4 Environmental information . 52
6.5 Instruction for equipment capable to be reused, repaired and upgraded . 53
7 Normal service, mounting and transport conditions . 53
8 Constructional and performance requirements . 53
8.1 Constructional requirements . 53
8.1.1 General . 53
8.1.2 Materials . 54
8.1.3 Current-carrying parts and their connections . 54
8.1.4 Clearances and creepage distances . 54
8.1.5 Actuator . 55
8.1.6 Indication of the contact position . 55
8.1.7 Additional requirements for equipment suitable for isolation . 55
8.1.8 Terminals . 56
8.1.9 Additional requirements for equipment provided with a neutral pole . 56
8.1.10 Provisions for protective earthing . 56
8.1.11 Enclosures for equipment . 56
8.1.12 Degrees of protection of enclosed equipment . 56
8.1.13 Conduit pull-out, torque and bending with metallic conduits . 56
8.1.14 Limited energy source . 57
8.1.15 Stored charge energy circuit . 59
8.1.16 Fault and abnormal conditions . 59
8.1.17 Short-circuit and overload protection of ports . 60
8.1.18 Use of voltage transient limiting device . 60
8.2 Performance requirements . 60
8.2.1 Operating conditions . 60
8.2.2 Temperature-rise . 66
8.2.3 Dielectric properties . 69
8.2.4 Normal load and overload performance requirements . 70
8.2.5 Co-ordination with short-circuit protective devices . 75
8.3 Electromagnetic compatibility (EMC) . 77
8.3.1 General . 77
8.3.2 Immunity . 78
8.3.3 Emission . 78
8.4 Embedded software . 79
8.5 Security . 79
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9 Tests . 79
9.1 Kinds of test . 79
9.1.1 General . 79
9.1.2 Type tests . 79
9.1.3 Routine tests . 79
9.1.4 Sampling tests . 80
9.1.5 Special tests . 80
9.2 Compliance with constructional requirements . 81
9.2.1 General . 81
9.2.2 Electrical performance of screwless-type clamping units . 81
9.2.3 Ageing test for screwless-type clamping units . 82
9.2.4 Limited energy source test . 82
9.2.5 Breakdown of components . 83
9.2.6 Wire flexing test . 83
9.3 Compliance with performance requirements . 84
9.3.1 Test sequences . 84
9.3.2 General test conditions . 84
9.3.3 Performance under no load, normal load and overload conditions . 85
9.3.4 Performance under short-circuit conditions . 98
9.3.5 Overload current withstand capability of contactors and IMPSDs . 104
9.3.6 Routine tests and sampling tests . 104
9.4 EMC tests . 106
9.4.1 General . 106
9.4.2 Immunity . 106
9.4.3 Emission . 108
Annex A (normative) Marking and identification of terminals of contactors, starters and
associated overload relays . 110
A.1 General . 110
A.2 Marking and identification of terminals of main circuits . 110
A.3 Marking and identification of terminals of overload relays . 110
Annex B (normative) Special tests . 112
B.1 General . 112
B.2 Mechanical durability . 112
B.2.1 General . 112
B.2.2 Verification of mechanical durability . 112
B.3 Electrical durability . 114
B.3.1 General . 114
B.3.2 Results to be obtained . 115
B.3.3 Statistical analysis of test results for contactors or starters . 115
B.4 Co-ordination at the crossover current between the starter and associated
SCPD . 116
B.4.1 General . 116
B.4.2 Condition for the test for the verification of co-ordination at the
crossover current by a direct method . 116
B.4.3 Test currents and test circuits . 116
B.4.4 Test procedure and results to be obtained . 117
B.4.5 Verification of co-ordination at the crossover current by an indirect
method . 117
IEC 60947-4-1:2023 © IEC 2023 – 5 –
Annex C (informative) Electric motor evolutions and motor starting methods . 120
C.1 General . 120
C.1.1 Major changes on the market concerning electrical motors . 120
C.1.2 Electric motor characteristics . 121
C.1.3 Efficiency motor analysis . 121
C.1.4 Impacts on switchgear and controlgear . 123
C.2 Typical variants direct-on-line starters. 123
C.3 Functional aspects of motor starters . 126
C.4 Currents and torques during a star-delta start . 128
C.5 Currents and torques during an auto-transformer start . 131
C.6 Currents waveform of the different modes of operation of a starter . 133
Annex D (informative) Items subject to agreement between manufacturer and user . 135
Annex E (Void) . 136
Annex F (normative) Requirements for auxiliary contact linked with power contact
(mirror contact) . 137
F.1 Application and object . 137
F.1.1 Application . 137
F.1.2 Object . 137
F.2 Characteristics . 137
F.3 Product information . 137
F.4 Normal service, mounting and transport conditions . 138
F.5 Constructional and performance requirements . 138
F.6 Tests . 138
F.6.1 General . 138
F.6.2 Tests on products in a new condition . 138
F.6.3 Test after conventional operational performance (defined under
Table 10) . 139
Annex G (informative) Rated operational currents and rated operational powers of
switching devices for electrical motors . 140
G.1 General . 140
G.2 Rated operational powers and rated operational currents . 140
Annex H (normative) Extended functions to electronic overload relays . 144
H.1 General . 144
H.2 Limits of operation of control functions . 144
H.2.1 General . 144
H.2.2 Limits of electronic overload relay with main circuit undervoltage
restarting function . 144
H.3 Test of the control functions . 144
Annex I (informative) AC-1 contactors for use with semiconductor controlled motor
load 145
Annex J (Void) . 146
Annex K (normative) Procedure to determine data for electromechanical contactors
used in functional safety applications . 147
K.1 General . 147
K.2 Test requirements . 147
K.3 Characterization of a failure mode . 147
K.4 Failure ratios of a contactor . 147
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Annex L (normative) Assessment procedure for electromechanical overload protection
used in safety applications and especially in explosive atmospheres . 149
L.1 Application and object . 149
L.1.1 Application . 149
L.1.2 Object . 149
L.2 Procedure . 149
L.2.1 General . 149
L.2.2 Safety design process . 150
L.3 Requirements . 150
L.3.1 General . 150
L.3.2 Safety plan . 150
L.3.3 Design . 151
L.3.4 Failure mode and effects analysis of the safety function . 151
L.3.5 Design plan . 152
L.3.6 Verification . 152
L.3.7 Function assessed . 152
L.4 Documentation . 152
L.4.1 Technical safety documentation . 152
L.4.2 Safety instructions . 152
L.5 Example. 153
L.5.1 architecture description . 153
L.5.2 FMEA . 154
Annex M (normative) DC contactors for use in photovoltaic (PV) applications . 162
M.1 Application . 162
M.2 Object . 162
M.3 Classification . 162
M.4 Characteristics . 162
M.4.1 General . 162
M.4.2 Rated impulse withstand voltage. 162
M.4.3 Utilization category . 163
M.5 Product information . 163
M.6 Normal service, mounting and transport conditions . 164
M.6.1 General . 164
M.6.2 Ambient air temperature . 164
M.6.3 Altitude . 164
M.7 Constructional and performance requirements . 164
M.7.1 Constructional requirements . 164
M.7.2 Performance requirements . 164
M.7.3 Electromagnetic compatibility (EMC) . 165
M.8 Tests . 166
M.8.1 General . 166
M.8.2 Type tests . 166
M.8.3 Making and breaking capacities and conventional operational
performance . 166
M.8.4 Thermal cycling test . 166
M.8.5 Climatic test. 167
M.8.6 Dielectric test . 167
M.8.7 Critical load current test . 167
M.8.8 Mechanical and electrical properties of terminals . 168
IEC 60947-4-1:2023 © IEC 2023 – 7 –
M.8.9 Degree of protection of enclosed contactors . 168
M.8.10 EMC . 168
M.8.11 Clearance and creepage distances . 168
Annex N (normative) Additional requirements and tests for equipment with protective
separation . 169
N.1 General . 169
N.2 Terms and definitions . 169
N.3 Requirements . 169
N.3.1 Test method for implementing protective impedance . 169
N.3.2 Touch current measurement . 170
Annex O (normative) Load monitoring indicators . 172
O.1 General . 172
O.2 Indicators list . 172
O.3 Uncertainty . 174
O.4 Tests . 175
O.4.1 Routine tests . 175
O.4.2 Type tests . 175
Annex P (normative) Short-circuit breaking tests of MPSD . 177
P.1 General test conditions . 177
P.2 Rated service short-circuit breaking capacity . 178
P.2.1 General . 178
P.2.2 Test of rated service short-circuit breaking capacity. 178
P.2.3 Verification of operational performance capability . 178
P.2.4 Verification of dielectric withstand . 178
P.2.5 Verification of temperature-rise . 179
P.2.6 Verification of overload releases . 179
P.3 Rated ultimate short-circuit breaking capacity . 179
P.3.1 General . 179
P.3.2 Verification of overload releases . 179
P.3.3 Test of rated ultimate short-circuit breaking capacity . 180
P.3.4 Verification of dielectric withstand . 180
P.3.5 Verification of overload releases . 180
P.4 Test of MPSD for IT system . 180
P.4.1 General . 180
P.4.2 Individual pole short-circuit . 181
P.4.3 Verification of dielectric withstand . 181
P.4.4 Verification of overload releases . 181
P.4.5 Marking . 182
Bibliography .
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SIST EN IEC 60947-4-1:2025는 저전압 스위치기어 및 제어 장치의 중요한 표준으로, 전기 기계적 접촉기 및 모터 스타터에 대한 지침을 제공합니다. 이 문서는 특히 모터 보호 스위칭 장치(MPSD 및 IMPSD), 접촉기 릴레이의 액추에이터 및 접촉기 회로와 관련된 전용 부품에 적용되며, 1,000V AC 또는 1,500V DC를 초과하지 않는 배전 회로, 모터 회로 및 기타 하중 회로에 연결될 수 있는 장치를 대상으로 합니다. 이 표준의 강점 중 하나는 기술적 변경 사항이 포함되어 있다는 점입니다. 특히, IMPSD와 같은 순간적 모터 보호 기능이 정의되어 있으며, 다양한 장비의 종류가 명확하게 구분되었습니다. 모터의 과부하 보호 방법에 대한 세부 사항도 포함되어 있어, 사용자들이 보다 안전하게 설비를 운영할 수 있도록 지원합니다. 또한, 최신 국제 표준인 IEC 61095:2023의 AC-7d를 채택함으로써, 최신 기술 동향에 기반한 적용성을 보장합니다. 또한, SIST EN IEC 60947-4-1:2025에서는 기준 문서와 관련된 환경적 측면에 대한 참고 자료도 제공하여, 현대의 기후 변화에 대응하는 지속 가능한 솔루션을 제시합니다. 전압 변동 한계, 온도 제약이 있는 접근 가능한 부품, 및 사이버 보안 측면에 대한 언급은 이러한 시대의 필요에 부합하는 중요한 요소입니다. 마지막으로, 표준의 개정판은 이전 판에서의 기술적 검토를 통해 발생한 진화를 반영하며, 특히 발전 가능한 분야에 대한 사례를 제공함으로써 사용자들에게 매우 유용한 자료가 됩니다. 이러한 모든 요소들은 SIST EN IEC 60947-4-1:2025가 관련 산업에서의 신뢰성과 안전성을 더욱 강화하는 데 기여함을 보여줍니다.
SIST EN IEC 60947-4-1:2025の標準文書は、低電圧のスイッチギアおよび制御機器に関する重要な基準を定めており、特に電気機械的接触器およびモータースターターに関連しています。この標準は、電圧が1,000 V ACまたは1,500 V DCを超えない配電回路、モーター回路、および他の負荷回路に接続されることを目的とした様々な機器に適用されます。 本標準の主な強みは、最新の技術的改訂を反映している点です。特に、過負荷保護の方法や瞬時モーター保護スイッチング装置(IMPSD)に関する明確な指針が含まれており、これにより、使用者はより安全かつ効率的にデバイスを運用できるようになります。また、新たにAC-7dの導入や、移動に伴う配線に関する規定が設けられたことで、実用性も向上しています。 さらに、環境面への配慮が強調されており、IEC TS 63058やIEC TR 63216への参照が導入されています。これにより、EMC環境や埋め込まれたソフトウェアの設計、サイバーセキュリティに関する要求事項が整備され、現代の技術的ニーズに対応した構造が築かれています。 具体的な技術変更についても、接触器やスターターの適用範囲の明確化、電磁石消費電力測定方法の更新などが挙げられます。これらの改訂は、スイッチギアと制御機器の性能向上にも寄与しています。 総じて、SIST EN IEC 60947-4-1:2025は、低電圧スイッチギアおよび制御機器の設計と使用において不可欠な基準であり、製造業や電気関連の分野での適用性が非常に高く、技術的な信頼性を確保するための重要なガイドラインとなっています。
Die Norm SIST EN IEC 60947-4-1:2025 befasst sich mit der Niederspannungs-Schaltgeräte- und Steuerungstechnik, insbesondere mit elektromechanischen Kontaktoren und Motorstartern. Die vierte Auflage dieser Norm, die 2018 veröffentlicht wurde, wurde nun umfassend überarbeitet und durch diese fünfte Ausgabe ersetzt. Der umfassende Anwendungsbereich dieser Norm ist von großer Relevanz für Fachleute, da sie spezifische Anforderungen und Prüfstandards für verschiedene Arten von elektromechanischen Kontaktoren und Startern festlegt, die nicht nur in der Industrie, sondern auch in der Gebäudeautomation verwendet werden. Eine der wesentlichen Stärken der Norm liegt in ihren technischen Änderungen im Vergleich zur vorherigen Ausgabe. Die Norm definiert nun klar den Zweck, den Umfang und die Arten von Geräten, die unter ihre Regelungen fallen. Sie umfasst unter anderem motorische Schutzschaltgeräte, Aktuatoren von Kontaktoren und Kontakte, die ausschließlich für den Spulenstromkreis des Kontaktors oder Kontaktorenrelays bestimmt sind. Diese umfassende Abdeckung stellt sicher, dass alle relevanten Geräte berücksichtigt werden, was die Sicherheit und Effizienz in den entsprechenden Anwendungen erhöht. Ein weiterer wichtiger Aspekt ist die Einführung verbesserter Methoden zum Überlastschutz von Motoren sowie die Bezugnahme auf relevante Normen und technische Spezifikationen, wie beispielsweise IEC TS 63058 für umwelttechnische Aspekte. Zusätzlich beinhaltet die Norm Aktualisierungen in Bezug auf Temperaturgrenzen für zugängliche Teile und die Verwendung von Gerätschaften zur Begrenzung von Spannungstransienten. Durch die Einbeziehung innovativer Technologien und Verfahren, wie den Verweis auf IEC TS 63208 bezüglich Cybersicherheitsaspekten, zeigt die Norm ihre Relevanz für die heutigen Anforderungen in der Elektrotechnik. Des Weiteren garantieren die festgelegten Prüfstandards und Messmethoden, dass elektromechanische Kontaktoren und Starter eine erstklassige Performance und Zuverlässigkeit bieten, was insbesondere für Anwendungen in kritischen Umgebungen entscheidend ist. Die SIST EN IEC 60947-4-1:2025 ist damit nicht nur eine aktualisierte Norm, sondern ein umfassendes Dokument, das den aktuellen technologischen Entwicklungen Rechnung trägt und die Sicherheits- und Leistungsanforderungen für elektromechanische Kontaktoren und Motorstarter festlegt.
The SIST EN IEC 60947-4-1:2025 standard provides comprehensive guidelines for low-voltage switchgear and controlgear, specifically focusing on electromechanical contactors and motor-starters. Its scope encompasses a variety of equipment, including electromechanical contactors, starters, motor protective switching devices such as MPSD and IMPSD, contactor relay actuators, and accessories designed to enhance performance and safety. This standard is relevant for equipment operating with rated voltages not exceeding 1,000 V AC or 1,500 V DC and is crucial for ensuring safe and efficient operation in distribution circuits, motor circuits, and other load circuits. One of the key strengths of this standard is its up-to-date technical revision, which addresses significant changes from the previous edition. This includes a refined objective in the scope, clarification of equipment types, enhanced protection methods, and the adoption of new performance metrics like AC-7d from IEC 61095:2023. The revisions not only modernize the standard but also incorporate the latest advancements in technology and environmental considerations, as evidenced by references to IEC TS 63058 for environmental aspects and IEC TS 63208 for cybersecurity. The inclusion of updated methodologies for overload protection, accessible parts temperature limits, and specific references to wiring subject to movement highlights the standard's focus on safety and operational integrity. Additionally, the standard's emphasis on coordination between Motor Protective Switching Devices (MPSD) and Short Circuit Protective Devices (SCPD) shows a forward-thinking approach to system interoperability and safety compliance. The relevance of the SIST EN IEC 60947-4-1:2025 standard lies in its ability to serve multiple stakeholders in the electrical engineering and manufacturing industries. By establishing consistent criteria for electromechanical contactors and motor-starters, the standard aids manufacturers in ensuring product reliability and safety, while providing users and designers with a framework for selecting appropriate equipment. The document’s detailed technical specifications and updated safety measures are instrumental in supporting the ongoing evolution of low-voltage equipment within a rigorous regulatory environment.
La norme SIST EN IEC 60947-4-1:2025 se concentre sur les équipements de commande et de protection à basse tension, spécifiquement les contacteurs électromécaniques et les démarreurs de moteurs. Son champ d'application est clairement défini, couvrant les dispositifs de commutation de protection de moteur (MPSD et IMPSD), les relais de contacteurs, ainsi que les accessoires dédiés. La norme est conçue pour des installations qui ne dépassent pas 1 000 V AC ou 1 500 V DC, ce qui en fait un texte de référence essentiel pour les applications industrielles et commerciales. Parmi les forces majeures de cette norme, on note sa modernisation par rapport à la quatrième édition de 2018. Cette nouvelle édition apporte des changements techniques significatifs, tels que l'introduction de dispositifs de commutation de protection de moteur instantanés (IMPSD) et des méthodes de protection contre les surcharges améliorées pour les moteurs. De plus, l’adoption de définitions et de classifications actualisées renforce la clarté et la précision, garantissant que les utilisateurs peuvent facilement comprendre et appliquer les exigences. La pertinence de la norme SIST EN IEC 60947-4-1:2025 est également renforcée par son intégration de références à d'autres normes IEC, telles que l'IEC TS 63058 pour les aspects environnementaux et l'IEC TR 63216 concernant les environnements EMC. Ces ajouts démontrent l'engagement envers une conception durable et la prise en compte des exigences modernes en matière de cybersécurité et de logiciel embarqué, ce qui est crucial dans un monde de plus en plus connecté. En outre, les améliorations apportées à la méthode de mesure de la consommation d'énergie des électroaimants et la détermination du courant de charge critique pour les applications photovoltaïques montrent une volonté d’adapter les normes aux évolutions technologiques et aux nouvelles pratiques dans le secteur. Dans l'ensemble, la norme SIST EN IEC 60947-4-1:2025 représente un cadre robuste pour la mise en œuvre sécurisée et efficace de contacteurs et démarreurs de moteurs, répondant ainsi aux besoins contemporains de l'industrie tout en favorisant l'harmonisation au niveau international des pratiques et des équipements.
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