SIST EN IEC 60974-3:2020

Arc welding equipment - Part 3: Arc striking and stabilizing devices (IEC 60974-3:2019)

This document  specifies safety requirements for industrial and professional ARC STRIKING and ARC STABILIZING DEVICES used in arc welding and allied processes. This document is applicable to ARC STRIKING and STABILIZING DEVICES which are stand-alone (separate from the welding equipment) or built in (housed in a single enclosure with other arc welding equipment).

Lichtbogenschweißeinrichtungen - Teil 3: Lichtbogenzünd- und -stabilisierungseinrichtungen (IEC 60974-3:2019)

Matériel de soudage à l'arc - Partie 3: Dispositifs d'amorçage et de stabilisation de l'arc (IEC 60974-3:2019)

La présente partie de l'IEC 60974 spécifie les exigences de sécurité pour les dispositifs d'amorçage et de stabilisation industriels et professionnels utilisés en soudage à l'arc et les procédés connexes.
Ce document s'applique aux DISPOSITIFS D'AMORÇAGE ET DE STABILISATION DE L'ARC qui sont indépendants (séparés du matériel de soudage) ou incorporés (intégrés dans une seule enveloppe avec d'autres matériels de soudage à l'arc).
NOTE 1 Le coupage à l'arc plasma et la projection au plasma sont des exemples de procédés connexes typiques.
NOTE 2 Le présent document ne contient pas les exigences de compatibilité électromagnétique (CEM).

Oprema za obločno varjenje - 3. del: Obločni udari in stabilizatorji (IEC 60974-3:2019)

Ta dokument določa varnostne zahteve za industrijske in strokovne OBLOČNE UDARE in OBLOČNE STABILIZATORJE, ki se uporabljajo pri obločnem varjenju in povezanih postopkih Ta dokument se uporablja za samostojne OBLOČNE UDARE in STABILIZATORJE (ločene od opreme za varjenje) ali za vgrajene (v skupnem ohišju z drugo opremo za obločno varjenje).

General Information

• Status: Published
• Publication Date: 16-Dec-2019
• ICS: 25.160.30 - Welding equipment
• Technical Committee: I09 - Imaginarni 09
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 12-Dec-2019
• Due Date: 16-Feb-2020
• Completion Date: 17-Dec-2019
• 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
• Directive: 2014/53/EU - Directive 2014/53/EU of The European Parliament and of the Council of 16 April 2014 on the harmonisation of the laws of the Member States relating to the making available on the market of radio equipment and repealing Directive 1999/5/EC
• Ref Project: EN IEC 60974-3:2019 - Arc welding equipment - Part 3: Arc striking and stabilizing devices

Relations

• Replaces: SIST EN 60974-3:2014 - Arc welding equipment - Part 3: Arc striking and stabilizing devices
• Effective Date: 12-Nov-2019

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN IEC 60974-3:2020
01-februar-2020
Nadomešča:
SIST EN 60974-3:2014
Oprema za obločno varjenje - 3. del: Obločni udari in stabilizatorji (IEC 60974-
3:2019)
Arc welding equipment - Part 3: Arc striking and stabilizing devices (IEC 60974-3:2019)
Lichtbogenschweißeinrichtungen - Teil 3: Lichtbogenzünd- und -
stabilisierungseinrichtungen (IEC 60974-3:2019)
Matériel de soudage à l'arc - Partie 3: Dispositifs d'amorçage et de stabilisation de l'arc
(IEC 60974-3:2019)
Ta slovenski standard je istoveten z: EN IEC 60974-3:2019
ICS:
25.160.30 Varilna oprema Welding equipment
SIST EN IEC 60974-3:2020 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN IEC 60974-3:2020

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SIST EN IEC 60974-3:2020


EUROPEAN STANDARD EN IEC 60974-3

NORME EUROPÉENNE

EUROPÄISCHE NORM
November 2019
ICS 25.160.30 Supersedes EN 60974-3:2014 and all of its amendments
and corrigenda (if any).
English Version
Arc welding equipment - Part 3: Arc striking and stabilizing
devices
(IEC 60974-3:2019)
Matériel de soudage à l'arc - Partie 3: Dispositifs Lichtbogenschweißeinrichtungen - Teil 3: Lichtbogenzünd-
d'amorçage et de stabilisation de l'arc und -stabilisierungseinrichtungen
(IEC 60974-3:2019) (IEC 60974-3:2019)
This European Standard was approved by CENELEC on 2019-03-06. 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 60974-3:2019 E

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SIST EN IEC 60974-3:2020
EN IEC 60974-3:2019 (E)
European foreword
The text of document 26/671/FDIS, future edition 4 of IEC 60974-3, prepared by IEC/TC 26 "Electric
welding" was submitted to the IEC-CENELEC parallel vote and approved by CENELEC as
EN IEC 60974-3:2019.
The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2020-05-08
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2022-11-08
document have to be withdrawn

This document supersedes EN 60974-3:2014 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.

Endorsement notice
The text of the International Standard IEC 60974-3:2019 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 standards
indicated:
IEC 60974 (series) NOTE Harmonized as EN IEC 60974 (series)
IEC 60384-14 NOTE Harmonized as EN 60384-14

2

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SIST EN IEC 60974-3:2020
EN IEC 60974-3:2019 (E)
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 60974-1 2017 Arc welding equipment - Part 1: Welding power EN IEC 60974-1 2018
sources
+ A1 2019  + A1 2019
IEC 60974-7 2013 Arc welding equipment - Part 7: Torches EN 60974-7 2013
IEC 61140 -  Protection against electric shock - Common EN 61140 2016
aspects for installation and equipment
3

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SIST EN IEC 60974-3:2020
EN IEC 60974-3:2019 (E)
Annex ZZ
(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 standardization request relating to
harmonized 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 harmonization 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 ZZ.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 ZZ.1 – Correspondence between this European standard and Annex I of Directive
2014/35/EU [2014 OJ L96]
Clause(s) / sub-clause(s)
Safety objectives of
Remarks / Notes
Directive 2014/35/EU
of this EN
1(a) Clauses 15, 17
1(b) Clause 17.1
Testing during periodic maintenance
1(c) or after repair is covered in separate
standards
Clauses 6.1, 6.2, 6.3, 10, 11,
2(a)
12, 17.1
Hazards arising from electric,
magnetic, and electromagnetic fields,
Clauses 6.1, 6.2, 6.3, 7, 11,
2(b) other ionizing and non-ionizing
12
radiation are covered in separate
standards
Acoustic noise is covered in separate
2(c) Clauses 6.2, 9, 10,14
standards
2(d) Clause 6.1
3(a) Clause 14
Functional safety is covered in
separate standards
3(b) Clauses 4, 6.2, 10, 14
Safety-related security is covered in
separate standards
3(c) Clause 9
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.
4

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SIST EN IEC 60974-3:2020



IEC 60974-3

®


Edition 4.0 2019-01




INTERNATIONAL



STANDARD




NORME



INTERNATIONALE











Arc welding equipment –

Part 3: Arc striking and stabilizing devices




Matériel de soudage à l’arc –

Partie 3: Dispositifs d'amorçage et de stabilisation de l'arc
















INTERNATIONAL

ELECTROTECHNICAL

COMMISSION


COMMISSION

ELECTROTECHNIQUE


INTERNATIONALE




ICS 25.160.30 ISBN 978-2-8322-6498-0



Warning! Make sure that you obtained this publication from an authorized distributor.

Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.

® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale

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SIST EN IEC 60974-3:2020
– 2 – IEC 60974-3:2019 © IEC 2019
CONTENTS
FOREWORD . 4
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 Environmental conditions . 7
5 Tests . 7
5.1 Test conditions . 7
5.2 Measuring instruments . 7
5.3 Conformity of components . 7
5.4 Type tests . 7
5.5 Routine tests. 8
5.5.1 Stand-alone unit . 8
5.5.2 Built-in unit . 8
6 Protection against electric shock . 8
6.1 Insulation . 8
6.1.1 General . 8
6.1.2 Clearances . 8
6.1.3 Creepage distances . 8
6.1.4 Insulation resistance . 9
6.1.5 Dielectric strength . 9
6.2 Protection against electric shock in normal service (direct contact) . 10
6.3 Protection against electric shock in case of a fault condition (indirect
contact) . 10
6.4 Protective provision . 10
7 Thermal requirements . 10
8 Thermal protection. 10
9 Abnormal operation . 10
10 Connection to the supply network . 11
11 Output . 11
11.1 Rated peak voltage . 11
11.2 Impulse current . 12
11.2.1 Risk of electric shock . 12
11.2.2 Electric charge. 12
11.2.3 Direct contact . 12
11.2.4 Series contact. 13
11.3 Mean energy . 14
11.4 Output circuit capacitance discharging . 15
11.5 Additional requirements . 15
12 Control circuits . 16
13 Hazard reducing device . 16
14 Mechanical provisions . 16
15 Rating plate . 16
15.1 General requirements . 16
15.2 Description . 17
15.3 Contents . 17

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IEC 60974-3:2019 © IEC 2019 – 3 –
16 Adjustment of the output . 18
17 Instructions and markings . 18
17.1 Instructions . 18
17.2 Markings . 18
Annex A (informative) Examples of coupling systems for arc striking and stabilizing
devices . 19
Annex B (informative) Example of a rating plate . 20
Bibliography . 21

Figure 1 – Rated peak voltage . 11
Figure 2 – Measurement of electric charge of impulse current. 12
Figure 3 – Measuring circuit for direct contact . 13
Figure 4 – Measuring circuit for serial contact . 14
Figure 5 – Measurement of mean energy . 15
Figure 6 – Measuring circuit for capacitance discharging . 15
Figure 7 – Rating plate . 17
Figure A.1 – Examples of coupling systems for arc striking and stabilizing devices . 19
Figure B.1 – Stand-alone unit . 20

Table 1 – Minimum clearances and creepage distances for arc striking and stabilizing
circuits . 9
Table 2 – Maximum peak voltages . 11

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INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________

ARC WELDING EQUIPMENT –

Part 3: Arc striking and stabilizing 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
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.
International Standard IEC 60974-3 has been prepared by IEC technical committee 26:
Electric welding.
This fourth edition cancels and replaces the third edition published in 2013 and constitutes a
technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
• changes induced by the publication of IEC 60974-1:2017;
• reference to IEC 60974-1:2017/AMD1:2019in Clause 2;
• Figure 2 is updated where a subtraction of the proportion of the no-load voltage is shown;
• requirement for safe operation of the arc striking and stabilising devices in the event of
failure, in 11.5;
• requirements for the rating plate as in IEC 60974-1:2017, Clause 15.

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SIST EN IEC 60974-3:2020
IEC 60974-3:2019 © IEC 2019 – 5 –
The text of this International Standard is based on the following documents:
FDIS Report on voting
26/671/FDIS 26/676/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.
In this document, the following print types are used:
– conformity statements: in italic type.
– terms used throughout this document which have been defined in Clause 3: SMALL CAPITALS.
This International Standard is to be read in conjunction with IEC 60974-1:2017.
A list of all the parts in the IEC 60974 series, published under the general title Arc welding
equipment, 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.

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ARC WELDING EQUIPMENT –

Part 3: Arc striking and stabilizing devices



1 Scope
This part of IEC 60974 specifies safety requirements for industrial and professional ARC
STRIKING and ARC STABILIZING DEVICES used in arc welding and allied processes.
This document is applicable to ARC STRIKING and STABILIZING DEVICES which are stand-alone
(separate from the welding equipment) or built in (housed in a single enclosure with other arc
welding equipment).
NOTE 1 Typical allied processes are, for example, plasma arc cutting and arc spraying.
NOTE 2 This document does not include electromagnetic compatibility (EMC) requirements.
2 Normative references
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.
IEC 60974-1:2017, Arc welding equipment – Part 1: Welding power sources
IEC 60974-1:2017/AMD1:2019
IEC 60974-7:2013, Arc welding equipment – Part 7: Torches
IEC 61140, Protection against electric shock – Common aspects for installation and
equipment
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60974-1 and
IEC 60974-7 and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1
arc striking device
device which superimposes a voltage on the welding circuit to ignite an arc
3.2
arc stabilizing device
device which superimposes a voltage on the welding circuit to maintain an arc

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SIST EN IEC 60974-3:2020
IEC 60974-3:2019 © IEC 2019 – 7 –
3.3
arc striking voltage
voltage superimposed on the no-load voltage to ignite an arc
3.4
arc stabilizing voltage
voltage superimposed on the arc voltage to maintain the arc
4 Environmental conditions
As specified in IEC 60974-1:2017, Clause 4.
5 Tests
5.1 Test conditions
As specified in 5.1 of IEC 60974-1:2017.
5.2 Measuring instruments
The accuracy of measuring instruments shall be as follows:
a) electrical measuring instruments: class 1 (±1 % of full-scale reading), except for the
measurement of insulation resistance and dielectric strength where the accuracy of the
measuring instruments is not specified, but shall be taken into account for the
measurement;
b) thermometer: ±2 K;
c) high-voltage probe: ±5 %.
5.3 Conformity of components
As specified in 5.3 of IEC 60974-1:2017/AMD1:2019.
5.4 Type tests
As a condition of conformity, the type tests given below shall be carried out on stand-alone
units in the following sequence with no drying time between f), g) and h):
a) visual inspection, as defined in 3.1.7 of IEC 60974-1:2017;
b) insulation resistance, as specified in 6.1.4 of IEC 60974-1:2017 (preliminary check);
c) enclosure, as specified in 14.2 of IEC 60974-1:2017;
d) handling means, as specified in 14.3 of IEC 60974-1:2017;
e) drop withstand, as specified in 14.4 of IEC 60974-1:2017;
f) protection provided by the enclosure, as specified in 6.2.1 of IEC 60974-1:2017;
g) insulation resistance, as specified in 6.1.4 of IEC 60974-1:2017;
h) dielectric strength, as specified in 6.1.5 of IEC 60974-1:2017;
i) visual inspection, as defined in 3.1.7 of IEC 60974-1:2017.
Rated arc striking and stabilizing peak voltage shall be measured in accordance with 11.1 in
any convenient sequence of type tests but before verifying mechanical provisions.
The other type tests included in this document and not listed here shall be carried out in any
convenient sequence.

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5.5 Routine tests
5.5.1 Stand-alone unit
All routine tests shall be carried out on each stand-alone unit in the following sequence:
a) visual inspection (as defined in 3.1.7 of IEC 60974-1:2017);
b) continuity of the protective circuit (as specified in Clause 10 and, if applicable, 10.5.1 of
IEC 60974-1:2017);
c) dielectric strength (as specified in 6.1.5 of IEC 60974-1:2017);
d) high-voltage circuit test: working voltage shall be applied to high-voltage circuits to
establish insulation integrity as specified by the manufacturer;
NOTE No-load voltage and connection of the return cable, either to the ground circuit or isolated, affects
working voltage.
e) visual inspection (as defined in 3.1.7 of IEC 60974-1:2017).
5.5.2 Built-in unit
The following routine test shall be carried out on each built-in unit in any convenient sequence
for the power source (as specified in 5.5 of IEC 60974-1:2017):
High-voltage circuit test: working voltage shall be applied to high-voltage circuits to
establish insulation integrity as specified by the manufacturer.
NOTE No-load voltage and connection of the return cable, either to the ground circuit or isolated, affects
working voltage.
6 Protection against electric shock
6.1 Insulation
6.1.1 General
Subclause 6.1.1 of IEC 60974-1:2017 applies.
6.1.2 Clearances
The minimum clearances for high-voltage components shall be in accordance with Table 1.
The minimum clearance for other components shall be in accordance with 6.1.2 of
IEC 60974-1:2017.
Conformity shall be checked by measurement and visual inspection.
6.1.3 Creepage distances
The minimum creepage distances for arc striking and stabilizing circuits shall be in
accordance with Table 1. The minimum creepage distances for other components shall be in
accordance with 6.1.3 of IEC 60974-1:2017.
Conformity shall be checked by measurement and visual inspection.

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Table 1 – Minimum clearances and creepage distances
for arc striking and stabilizing circuits
a b b
Rated peak voltage Clearance Creepage distance
kV mm mm
3 3 6,3
6 5,5 10
8 8 12,5
10 11 16
12 14 20
15 18 25
18 25 30
20 30 35

NOTE These values apply to circuits which are designed in accordance with 11.3.
a
Rated peak voltage shall be measured in accordance with 11.1.
b
Interpolation is allowed.

6.1.4 Insulation resistance
Subclause 6.1.4 of IEC 60974-1:2017 applies.
6.1.5 Dielectric strength
The output circuit of ARC STRIKING AND STABILIZING DEVICES and the insulation of coupling
components (for example, coupling transformers or coupling capacitors) shall withstand an
arc striking test voltage 20 % higher than the rated peak ARC STRIKING VOLTAGE at the
maximum pulse repetition rate of the device.
Alternatively, an AC test voltage with the same peak value of approximately sine waveform at
50 Hz or 60 Hz may be used for coupling components only. The maximum permissible setting
of the tripping current shall be 100 mA. The high voltage transformer shall deliver the
prescribed voltage up to the tripping current. Tripping is regarded as a flashover or a
breakdown.
NOTE 1 For the operator's safety, the lowest setting of the tripping curr
...