EN IEC 60947-9-1:2019

Low-voltage switchgear and controlgear - Part 9-1: Active arc-fault mitigation systems - Arc quenching devices

IEC 60947-9-1:2019 covers low-voltage arc quenching devices, hereinafter referred to as AQDs, which are intended to eliminate arc-faults in low-voltage assemblies (typically low-voltage switchgear and controlgear assemblies in accordance with the IEC 61439 series), by creating a lower impedance current path, to cause the arcing current to transfer to the new current path. This new current path is maintained until a short-circuit protection device (SCPD) interrupts the short-circuit current. AQDs are installed in low-voltage assemblies, connected to the main circuit, preferably as close as possible to all primary power sources. Their rated voltage does not exceed 1 000 V AC or 1 500 V DC.

Niederspannungsschaltgeräte - Aktive Systeme zur Verringerung von Lichtbogenfehlern - Teil 9-1: Lichtbogenlöschgeräte

Appareillage à basse tension - Partie 9-1: Systèmes actifs de limitation des défauts d'arc - Dispositifs d'extinction d'arc

L'IEC 60947-9-1:2019 couvre les dispositifs d’extinction d’arc à basse tension, ci-après appelés «AQD» (arc quenching devices). Ces appareils sont destinés à éliminer les défauts d’arc dans les ensembles à basse tension (en règle générale, des ensembles d'appareillage à basse tension conformes à la série IEC 61439) en créant un chemin de courant à impédance plus faible pour provoquer le transfert du courant d’arc vers ce nouveau chemin de courant. Ce nouveau chemin de courant est maintenu jusqu’à la coupure du courant de court-circuit par le DPCC. Les AQD sont installés dans les ensembles à basse tension, raccordés au circuit principal, de préférence le plus près possible de toutes les sources primaires d’alimentation. Leur tension assignée ne dépasse pas 1 000 V en courant alternatif ou 1 500 V en courant continu.

Nizkonapetostne stikalne in krmilne naprave - 9-1. del: Aktivni sistemi za blažitev učinkov okvarnega obloka - Naprave za gašenje obloka (IEC 60947-9-1:2019)

Ta del standarda IEC 60947 zajema nizkonapetostne naprave za gašenje obloka (AQD), ki so namenjene preprečevanju učinkov okvarnega obloka pri nizkonapetostnih sestavih (običajno pri sestavih nizkonapetostnih stikalnih in krmilnih naprav v skladu s skupino standardov IEC 61439), tako da se tvori zelo majhna impedanca, ki povzroči, da se obločni tok prenese na novo tokovno pot. Ta nova tokovna pot se ohranja, dokler naprava za zaščito pred kratkim stikom (SCPD) ne prekine kratkostičnega toka.
Naprave za gašenje obloka so nameščene v nizkonapetostnih sestavih in povezane na glavni tokokrog, po možnosti čim bližje vsem primarnim virom napajanja.
Njihova nazivna napetost ne presega 1000 V izmenične napetosti ali 1500 V enosmerne napetosti.
Ta dokument ne zajema:
• tipal, namenjenih odkrivanju učinkov okvarnega obloka;
• naprav, namenjenih proženju naprave za gašenje obloka;
• naprav, namenjenih prekinjanju učinkov okvarnega obloka;
• posebnih zahtev za naprave za gašenje obloka glede uporabe v eksplozivnih okoljih (npr. ATEX).

General Information

• Status: Published
• Publication Date: 23-May-2019
• Withdrawal Date: 23-May-2022
• ICS: 29.120.40 - Switches
• ICS: 29.130.20 - Low voltage switchgear and controlgear
• Technical Committee: CLC/TC 121A - Low-voltage switchgear and controlgear
• Drafting Committee: IEC/SC 121A - Low-voltage switchgear and controlgear
• Current Stage: 6060 - Document made available - Publishing
• Start Date: 24-May-2019
• Completion Date: 24-May-2019
• Directive: 2014/30/EU - Directive 2014/30/EU of the European Parliament and of the Council of 26 February 2014 on the harmonisation of the laws of the Member States relating to electromagnetic compatibility (recast)
• Directive: 2014/35/EU - Directive 2014/35/EU of the European Parliament and of the Council of 26 February 2014 on the harmonisation of the laws of the Member States relating to the making available on the market of electrical equipment designed for use within certain voltage limits
• Mandate: M/511 - Mandate to CEN, CENELEC and ETSI relating to harmonised standards in the field of the Low Voltage Directive
• Mandate: M/552 - [C(2016) 7641 final] Standardisation request as regards harmonised standards in support of Directive 2014/30/EU of the European Parliament and of the Council of 26 February 2014 on the harmonisation of the laws of the Member States relating to electromagnetic compatibility
• Ref Project: SIST EN IEC 60947-9-1:2019 - Low-voltage switchgear and controlgear - Active arc-fault mitigation systems - Part 9-1: Arc quenching devices (IEC 60947-9-1:2019)

Overview

EN IEC 60947-9-1:2019 (aligned with IEC 60947-9-1:2019) specifies requirements for arc quenching devices (AQDs) used in low‑voltage switchgear and controlgear assemblies. It covers AQDs that actively eliminate arc-faults in low‑voltage assemblies-typically switchgear and controlgear assemblies in accordance with the IEC 61439 series-by creating a lower‑impedance current path so that the arcing current transfers to that path until a short‑circuit protection device (SCPD) clears the fault. Rated voltages are limited to ≤ 1 000 V AC or ≤ 1 500 V DC. The standard is adopted by CLC/CENELEC and provides normative support for relevant EU Directives (EMC and Low Voltage).

Key Topics and Requirements

• Scope and definitions for Active Arc‑Fault Mitigation Systems and AQDs.
• Classification of AQDs:
  • By operation: single‑shot and resettable.
  • By mounting: fixed, withdrawable/plug‑in.
• Performance characteristics required: rated operational and insulation voltages, rated impulse withstand voltage, rated short‑time withstand current, maximum voltage drop in low‑impedance state, maximum operating time, permissible terminal temperatures, and number of operating cycles for resettable devices.
• Constructional requirements addressing mechanical and electrical design suitable for low‑voltage assemblies.
• Product information and marking: required data, installation/operation/maintenance instructions and labeling.
• Tests: type tests (performance and electromagnetic compatibility), routine tests (mechanical/electrical), and compliance testing under defined service and environmental conditions.
• Electromagnetic compatibility (EMC) requirements and references to EMC test standards.
• Informative rationale (Annex A) explaining voltage‑drop criteria for successful arc extinction.

Applications

• Integration into low‑voltage switchgear and controlgear assemblies to reduce arcing risk and improve personnel and equipment safety.
• Use in industrial power distribution, commercial electrical panels, renewable energy inverters and DC systems up to 1 500 V DC.
• Employed where rapid transfer of arcing current to a controlled low‑impedance path reduces arc energy before SCPD interruption.

Who Should Use This Standard

• Switchgear and AQD manufacturers
• Panel builders and assembly integrators
• Electrical design and safety engineers
• Testing laboratories, certification bodies, and conformity assessors
• Regulatory and standards professionals implementing EU EMC and Low Voltage Directive compliance

Related Standards

• IEC/EN 60947‑1 (General rules for low‑voltage switchgear and controlgear)
• IEC 61439 series (Low‑voltage switchgear and controlgear assemblies)
• IEC 60068‑2‑30 (Environmental testing)
• CISPR 11 / EN 55011 (EMC limits for industrial equipment)

Keywords: EN IEC 60947-9-1:2019, arc quenching devices, AQD, low‑voltage switchgear, active arc‑fault mitigation systems, IEC 60947-9-1:2019, IEC 61439, SCPD, EMC.

Standards Content (Sample)

SLOVENSKI STANDARD
01-julij-2019
Nizkonapetostne stikalne in krmilne naprave - 9-1. del: Aktivni sistemi za blažitev
učinkov okvarnega obloka - Naprave za gašenje obloka (IEC 60947-9-1:2019)
Low-voltage switchgear and controlgear - Active arc-fault mitigation systems - Part 9-1:
Arc quenching devices (IEC 60947-9-1:2019)
Niederspannungsschaltgeräte - Aktive Systeme zur Verringerung von Lichtbogenfehlern
- Teil 9-1: Lichtbogenlöschgeräte (IEC 60947-9-1:2019)
Appareillage à basse tension - Partie 9-1: Systèmes actifs de limitation des défauts d'arc
- Dispositifs d'extinction d'arc (IEC 60947-9-1:2019)
Ta slovenski standard je istoveten z: EN IEC 60947-9-1:2019
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 60947-9-1

NORME EUROPÉENNE
EUROPÄISCHE NORM
May 2019
ICS 29.120.40; 29.130.20
English Version
Low-voltage switchgear and controlgear - Part 9-1: Active arc-
fault mitigation systems - Arc quenching devices
(IEC 60947-9-1:2019)
Appareillage à basse tension - Partie 9-1: Systèmes actifs Niederspannungsschaltgeräte - Aktive Systeme zur
de limitation des défauts d'arc - Dispositifs d'extinction d'arc Verringerung von Lichtbogenfehlern - Teil 9-1:
(IEC 60947-9-1:2019) Lichtbogenlöschgeräte
(IEC 60947-9-1:2019)
This European Standard was approved by CENELEC on 2019-02-20. 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, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden,
Switzerland, Turkey 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
© 2019 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN IEC 60947-9-1:2019 E

European foreword
The text of document 121A/254/FDIS, future edition 1 of IEC 60947-9-1, 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) 2019-11-24
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2022-05-24
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 has been prepared under a mandate given to CENELEC by the European Commission
and the European Free Trade Association, and supports essential requirements of EU Directive(s).
For the relationship with EU Directives and the standardization requests see informative Annex ZZA
and Annex ZZB, which are integral parts of this document.
Endorsement notice
The text of the International Standard IEC 60947-9-1:2019 was approved by CENELEC as a
European Standard without any modification.

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.cenelec.eu.
Publication Year Title EN/HD Year

IEC 60068-2-30 2005 Environmental testing -- Part 2-30: Tests - EN 60068-2-30 2005
Test Db: Damp heat, cyclic (12 h + 12 h
cycle)
IEC 60417 Data- Graphical symbols for use on equipment - -
base
IEC 60947-1 2007 Low-voltage switchgear and controlgear -- EN 60947-1 2007
Part 1: General rules
+ A1 2010  + A1 2011
+ A2 2014  + A2 2014
IEC 61439 series Low-voltage switchgear and controlgear EN 61439 series
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
Annex ZZA
(informative)
Relationship between this European standard and the essential requirements
of Directive 2014/30/EU [2014 OJ L96] aimed to be covered
This European standard has been prepared under the European Commission standardisation request
C(2016) 7641 final of 30.11.2016 , ('M/552'), as regards harmonised standards in support of Directive
2014/30/EU relating to electromagnetic compatibility, to provide one voluntary means of conforming to
essential requirements of Directive 2014/30/EU of the European Parliament and of the Council of 26
February 2014 on the harmonisation of the laws of the Member States relating to electromagnetic
compatibility [2014 OJ L96].
Once this standard is cited in the Official Journal of the European Union under that Directive,
compliance with the normative clauses of this standard given in Table ZZA.1 confers, within the limits
of the scope of this standard, a presumption of conformity with the corresponding essential
requirements of that Directive, and associated EFTA regulations.
Table ZZA.1 – Correspondence between this European standard and Annex I of Directive
2014/30/EU [2014 OJ L96]
Clause(s) / sub-clause(s)
Essential requirements of
Remarks / Notes
Directive 2014/30/EU
of this EN
Annex I. 1(a) (electromagnetic 8.3, 9.3.2.2
disturbances)
Annex I. 1(b) (electromagnetic 8.3, 9.3.2.1
immunity)
WARNING 1: Presumption of conformity stays valid only as long as a reference to this European
standard is maintained in the list published in the Official Journal of the European Union. Users of this
standard should consult frequently the latest list published in the Official Journal of the European
Union.
WARNING 2: Other Union legislation may be applicable to the product(s) falling within the scope of
this standard.
COMMISSION IMPLEMENTING DECISION C(2016) 7641 final of 30.11.2016 on a standardisation request to the European
Committee for Standardisation, to the European Committee for Electrotechnical Standardisation and to the European
Telecommunications Standards Institute as regards harmonised standards in support of Directive 2014/30/EU of the European
Parliament and of the Council of 26 February 2014 on the harmonisation of the laws of the Member States relating to
electromagnetic compatibility.
Annex ZZB
(informative)
Relationship between this European standard and the safety objectives of
Directive 2014/35/EU [2014 OJ L96] aimed to be covered
This European standard has been prepared under a Commission’s standardisation request relating to
harmonised standards in the field of the Low Voltage Directive, M/511, to provide one voluntary means
of conforming to safety objectives of Directive 2014/35/EU of the European Parliament and of the
Council of 26 February 2014 on the harmonisation of the laws of the Member States relating to the
making available on the market of electrical equipment designed for use within certain voltage limits
[2014 OJ L96].
Once this standard is cited in the Official Journal of the European Union under that Directive,
compliance with the normative clauses of this standard given in Table ZZB.1 confers, within the limits
of the scope of this standard, a presumption of conformity with the corresponding safety objectives of
that Directive, and associated EFTA regulations.
Table ZZB.1 – Correspondence between this European standard and Annex I of Directive
2014/35/EU [2014 OJ L96]
Safety objectives of Clause(s) / sub-clause(s) of this EN Remarks/Notes
Directive 2014/35/EU
1 a) 6
1 b) 6
1 c) 1, 3, 4, 5, and 6.3
2 a) 8.1, 8.2, 9.3
2 b) 8.1, 9.3
2 c) 6.2, 6.3, 8.1, 9.3, 9.4
2 d) 8.1, 8.2, 9.3
3 a) 6.3, 8.1, 9.3, 9.4
3 b) 8.1, 9.3
3 c) - No hazard identified for products
falling under the scope of this
standard.
WARNING 1: Presumption of conformity stays valid only as long as a reference to this European
standard is maintained in the list published in the Official Journal of the European Union. Users of this
standard should consult frequently the latest list published in the Official Journal of the European
Union.
WARNING 2: Other Union legislation may be applicable to the product(s) falling within the scope of
this standard.
IEC 60947-9-1 ®
Edition 1.0 2019-01
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Low-voltage switchgear and controlgear –

Part 9-1: Active arc-fault mitigation systems – Arc quenching devices

Appareillage à basse tension –

Partie 9-1: Systèmes actifs de limitation des défauts d'arc – Dispositifs

d'extinction d'arc
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.120.40; 29.130.20 ISBN 978-2-8322-6404-1

– 2 – IEC 60947-9-1:2019 © IEC 2019
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 8
4 Classification . 8
4.1 According to the number of operations . 8
4.1.1 Single shot AQD . 8
4.1.2 Resettable AQD . 9
4.2 According to the mounting characteristics . 9
4.2.1 Fixed AQD . 9
4.2.2 Withdrawable or plug-in AQD . 9
5 Characteristics . 9
5.1 Rated operational voltage (U ) . 9
e
5.2 Rated insulation voltage (U ) . 9
i
5.3 Rated impulse withstand voltage (U ) . 9
imp
5.4 Rated short-time withstand current (I ) . 9
cw
5.5 Maximum voltage drop in low-impedance state . 9
5.6 Maximum operating time . 10
5.7 Number of operating cycles (of a resettable AQD) . 10
5.8 Maximum permissible temperature of the AQD main circuit terminals . 10
6 Product information . 10
6.1 Nature of information . 10
6.2 Marking . 10
6.3 Instructions for installation, operation, maintenance, decommissioning and
dismantling . 11
7 Normal service, mounting and transport conditions . 11
8 Constructional and performance requirements . 11
8.1 Constructional requirements . 11
8.2 Performance requirements . 12
8.3 Electromagnetic compatibility (EMC) . 12
9 Tests . 13
9.1 Kind of tests . 13
9.2 Compliance with constructional requirements . 13
9.3 Type tests . 13
9.3.1 Performance tests . 13
9.3.2 Electromagnetic compatibility tests . 15
9.4 Routine tests. 16
9.4.1 Closing operation. 16
9.4.2 Dielectric test . 16

IEC 60947-9-1:2019 © IEC 2019 – 3 –
Annex A (informative) Rationale for defining the maximum voltage drop value in low-
impedance state . 17
A.1 Condition for arc extinction . 17
A.2 Determination of minimum distance and corresponding voltage drop . 18
Bibliography . 19

Table 1 – Product information . 11

– 4 – IEC 60947-9-1:2019 © IEC 2019
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
LOW-VOLTAGE SWITCHGEAR AND CONTROLGEAR –

Part 9-1: Active arc-fault mitigation systems –
Arc quenching devices
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
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2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
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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.
International Standard IEC 60947-9-1 has been prepared by subcommittee SC121A: Low-
voltage switchgear and controlgear, of IEC technical committee 121: Switchgear and
controlgear and their assemblies for low voltage.
The text of this International Standard is based on the following documents:
FDIS Report on voting
121A/254/FDIS 121A/266/RVD
Full information on the voting for the approval of this International Standard can be found in
the report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.

IEC 60947-9-1:2019 © IEC 2019 – 5 –
A list of all parts in the IEC 60947 series, published under the general title Low-voltage
switchgear and controlgear, can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://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.
– 6 – IEC 60947-9-1:2019 © IEC 2019
INTRODUCTION
The effects of arc-faults inside an enclosure are more and more taken into consideration, both
from user safety and time-to-repair points of view. Protection against the effects of internal
arc-faults can be achieved through passive components (containment) or through active
components, also known as "active arc-fault mitigation systems".
Active arc-fault mitigation systems generally use internal arc-fault control devices (IACDs),
based on the effects of the arc (light, pressure, current or voltage harmonics, etc.), and an
actuator to eliminate the arc-fault.
This actuator can be an upstream circuit-breaker, which is tripped to interrupt the fault current,
or an arc quenching device that will transfer the fault to a dedicated low-impedance circuit,
before the short-circuit current is interrupted by the upstream short-circuit protective device
(SCPD).
The purpose of this document is to set the requirements for arc quenching devices, so that
the necessary safety is ensured and their performance can be fairly assessed.
Special requirements for environmental withstand (e.g. ambient temperature, damp heat,
shock, vibrations) are included, considering the high impact of a malfunction, either unwanted
operation (creation of a short-circuit) or failure to operate.
Requirements for internal arc-fault control devices are under development and will be
published as IEC 60947-9-2 .
Requirements for integration of internal arc-fault mitigation systems in power switchgear and
controlgear assemblies are under development and will be published as IEC TS 63107 .

___________
Under preparation. Stage at the time of publication: IEC/ACD 60947-9-2:2018.
Under preparation. Stage at the time of publication: IEC/PCC 63107:2018.

IEC 60947-9-1:2019 © IEC 2019 – 7 –
LOW-VOLTAGE SWITCHGEAR AND CONTROLGEAR –

Part 9-1: Active arc-fault mitigation systems –
Arc quenching devices
1 Scope
This part of IEC 60947 covers low-voltage arc quenching devices, hereinafter referred to as
AQDs, which are intended to eliminate arc-faults in low-voltage assemblies (typically low-
voltage switchgear and controlgear assemblies in accordance with the IEC 61439 series), by
creating a lower impedance current path, to cause the arcing current to transfer to the new
current path. This new current path is maintained until a short-circ
...