SIST EN 60243-1:2013

Electrical strength of insulating materials - Test methods - Part 1: Tests at power frequencies

This part of IEC 60243 provides test methods for the determination of short-time electric strength of solid insulating materials at power frequencies between 48 Hz and 62 Hz. This standard does not cover the testing of liquids and gases, although these are specified and used as impregnates or surrounding media for the solid insulating materials being tested. NOTE Methods for the determination of breakdown voltages along the surfaces of solid insulating materials are included.

/

Rigidité diélectrique des matériaux isolants - Méthodes d'essai - Partie 1: Essais aux fréquences industrielles

La CEI 60243-1:2013 fournit les méthodes d'essai pour la détermination de la rigidité diélectrique de courte durée des matériaux isolants solides, aux fréquences industrielles comprises entre 48 Hz et 62 Hz. La présente norme ne couvre pas la manière d'effectuer l'essai des liquides ou des gaz bien que ceux-ci soient spécifiés et utilisés comme imprégnants ou comme milieu ambiant pour l'essai des matériaux isolants solides. NOTE: Les méthodes pour déterminer les tensions de claquage en surface des matériaux isolants solides sont indiquées.

Električna prebojna trdnost izolacijskih materialov - 1. del: Preskušanje pri omrežnih frekvencah

Ta del standarda IEC 60243 podaja preskusne metode za določitev kratkoročne električne moči trdnih izolacijskih materialov pri obratovalnih frekvencah med 48 Hz in 62 Hz. Ta standard ne zajema preskušanja tekočin in plinov, čeprav so ti določeni in se uporabljajo kot sredstva za impregnacijo ali sredstva okrog trdnih izolacijskih materialov, ki se preskušajo. OPOMBA Metode za določitev prebojnih napetosti na površinah trdnih izolacijskih materialov so vključene.

General Information

• Status: Published
• Publication Date: 22-Jul-2013
• ICS: 17.220.99 - Other standards related to electricity and magnetism
• ICS: 29.035.01 - Insulating materials in general
• Technical Committee: IIZS - Insulating materials and systems
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 22-Jul-2013
• Due Date: 26-Sep-2013
• Completion Date: 23-Jul-2013
• Ref Project: EN 60243-1:2013 - Electric strength of insulating materials - Test methods - Part 1: Tests at power frequencies

Relations

• Replaces: SIST EN 60243-1:2001 - Electrical strength of insulating materials - Test methods -- Part 1: Tests at power frequencies
• Effective Date: 20-Dec-2011
• Revised: SIST EN 60243-1:2001 - Electrical strength of insulating materials - Test methods -- Part 1: Tests at power frequencies
• Effective Date: 06-May-2014
• Replaces: SIST EN 60243-1:2001 - Electrical strength of insulating materials - Test methods -- Part 1: Tests at power frequencies
• Effective Date: 29-Jan-2023
• Replaces: SIST EN 60243-1:2001 - Electrical strength of insulating materials - Test methods -- Part 1: Tests at power frequencies
• Effective Date: 07-Jun-2022

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN 60243-1:2013
01-september-2013
1DGRPHãþD
SIST EN 60243-1:2001
(OHNWULþQDSUHERMQDWUGQRVWL]RODFLMVNLKPDWHULDORYGHO3UHVNXãDQMHSUL
RPUHåQLKIUHNYHQFDK
Electrical strength of insulating materials - Test methods - Part 1: Tests at power
frequencies
/
Rigidité diélectrique des matériaux isolants - Méthodes d'essai - Partie 1: Essais aux
fréquences industrielles
Ta slovenski standard je istoveten z: EN 60243-1:2013
ICS:
17.220.99 Drugi standardi v zvezi z Other standards related to
elektriko in magnetizmom electricity and magnetism
29.035.01 Izolacijski materiali na Insulating materials in
splošno general
SIST EN 60243-1:2013 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN 60243-1:2013

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SIST EN 60243-1:2013

EUROPEAN STANDARD
EN 60243-1

NORME EUROPÉENNE
July 2013
EUROPÄISCHE NORM

ICS 17.220.99; 29.035.01 Supersedes EN 60243-1:1998


English version


Electric strength of insulating materials -
Test methods -
Part 1: Tests at power frequencies
(IEC 60243-1:2013)


Rigidité diélectrique des matériaux Elektrische Durchschlagfestigkeit von
isolants - Méthodes d'essai - isolierenden Werkstoffen -
Partie 1: Essais aux fréquences Prüfverfahren -
industrielles Teil 1: Prüfungen bei technischen
(CEI 60243-1:2013) Frequenzen
(IEC 60243-1:2013)




This European Standard was approved by CENELEC on 2013-04-30. 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, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom.

CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung

Management Centre: Avenue Marnix 17, B - 1000 Brussels


© 2013 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 60243-1:2013 E

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SIST EN 60243-1:2013
EN 60243-1:2013 - 2 -
Foreword
The text of document 112/237/FDIS, future edition 3 of IEC 60243-1, prepared by IEC/TC 112
"Evaluation and qualification of electrical insulating materials and systems" was submitted to the
IEC-CENELEC parallel vote and approved by CENELEC as EN 60243-1:2013.

The following dates are fixed:
(dop) 2014-01-30
• latest date by which the document has
to be implemented at national level by
publication of an identical national
standard or by endorsement
• latest date by which the national (dow) 2016-04-30
standards conflicting with the
document have to be withdrawn

This document supersedes EN 60243-1:1998.
EN 60243-1:2013 includes the following significant technical changes with respect to
EN 60243-1:1998:

The significant technical change with respect to the previous edition is that the current version now
includes an option for testing elastomeric materials.

Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC [and/or CEN] shall not be held responsible for identifying any or all such
patent rights.

Endorsement notice
The text of the International Standard IEC 60243-1:2013 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following note has to be added for the standard indicated :

IEC 60674-2 NOTE Harmonised as EN 60674-2.

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SIST EN 60243-1:2013
- 3 - EN 60243-1:2013
Annex ZA
(normative)

Normative references to international publications
with their corresponding European publications

The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.

NOTE  When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD
applies.

Publication Year Title EN/HD Year

IEC 60212 - Standard conditions for use prior to and EN 60212 -
during the testing of solid electrical insulating
materials


IEC 60296 - Fluids for electrotechnical applications - EN 60296 -
Unused mineral insulating oils for
transformers and switchgear


IEC 60455-2 - Resin based reactive compounds used for EN 60455-2 -
electrical insulation -
Part 2: Methods of test


IEC 60464-2 - Varnishes used for electrical insulation - EN 60464-2 -
Part 2: Methods of test


IEC 60684-2 - Flexible insulating sleeving - EN 60684-2 -
Part 2: Methods of test


IEC 60836 - Specifications for unused silicone insulating EN 60836 -
liquids for electrotechnical purposes


IEC 61099 - Insulating liquids - Specifications for unused EN 61099 -
synthetic organic esters for electrical
purposes


ISO 293 - Plastics - Compression moulding of test EN ISO 293 -
specimens of thermoplastic materials


ISO 294-1 - Plastics - Injection moulding of test EN ISO 294-1 -
specimens of thermoplastic materials -
Part 1: General principles, and moulding of
multipurpose and bar test specimens


ISO 294-3 - Plastics - Injection moulding of test EN ISO 294-3 -
specimens of thermoplastic materials -
Part 3: Small plates

ISO 295 - Plastics - Compression moulding of test EN ISO 295 -
specimens of thermosetting materials


ISO 10724 Series Plastics - Injection moulding of test EN ISO 10724 Series
specimens of thermosetting powder
moulding compounds (PMCs)

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SIST EN 60243-1:2013

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SIST EN 60243-1:2013



IEC 60243-1

®


Edition 3.0 2013-03




INTERNATIONAL



STANDARD




NORME



INTERNATIONALE











Electric strength of insulating materials – Test methods –

Part 1: Tests at power frequencies




Rigidité diélectrique des matériaux isolants – Méthodes d'essai –

Partie 1: Essais aux fréquences industrielles
















INTERNATIONAL

ELECTROTECHNICAL

COMMISSION


COMMISSION

ELECTROTECHNIQUE

PRICE CODE
INTERNATIONALE

CODE PRIX U


ICS 17.220.99; 29.035.01 ISBN 978-2-83220-696-6



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 60243-1:2013
– 2 – 60243-1 © IEC:2013
CONTENTS
FOREWORD . 4
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 7
4 Significance of the test . 7
5 Electrodes and specimens . 8
5.1 General . 8
5.2 Tests perpendicular to the surface of non-laminated materials and normal to
laminate of laminated materials . 8
5.2.1 Boards and sheet materials, including pressboards, papers, fabrics
and films . 8
5.2.2 Tapes, films and narrow strips . 9
5.2.3 Flexible tubing and sleeving . 9
5.2.4 Rigid tubes (having an internal diameter up to and including 100 mm) . 9
5.2.5 Tubes and hollow cylinders (having an internal diameter greater than
100 mm) . 10
5.2.6 Cast and moulded materials . 10
5.2.7 Shaped solid pieces . 11
5.2.8 Varnishes . 11
5.2.9 Filling compounds . 11
5.3 Tests parallel to the surface of non-laminated materials and parallel to the
laminate of laminated materials . 11
5.3.1 General . 11
5.3.2 Parallel plate electrodes . 11
5.3.3 Taper pin electrodes . 12
5.3.4 Parallel cylindrical electrodes . 12
5.4 Test specimens . 12
5.5 Distance between electrodes . 12
6 Conditioning before tests . 13
7 Surrounding medium . 13
7.1 General . 13
7.2 Tests in air at elevated temperature . 13
7.3 Tests in liquids . 13
7.4 Tests in solid materials . 14
8 Electrical apparatus . 14
8.1 Voltage source . 14
8.2 Voltage measurement . 14
9 Procedure. 15
10 Mode of increase of voltage . 15
10.1 Short-time (rapid-rise) test . 15
10.2 20 s step-by-step test . 16
10.3 Slow rate-of-rise test (120 s. 240 s) . 16
10.4 60 s step-by-step test . 17
10.5 Very slow rate-of-rise test (300 s. 600 s) . 17
10.6 Proof tests . 17
11 Criterion of breakdown . 17
12 Number of tests . 18

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SIST EN 60243-1:2013
60243-1 © IEC:2013 – 3 –
13 Report . 18
Annex A (informative) Treatment of experimental data . 25
Bibliography . 26

Figure 1 – Electrode arrangements for tests on boards and sheets perpendicular to the
surface . 19
Figure 2 – Typical example of electrode arrangement for tests on tapes perpendicular
to the surface (see 5.2.2) . 20
Figure 3 – Electrode arrangement for tests perpendicular to the surface on tubes and
cylinders with internal diameter greater than 100 mm. 20
Figure 4 – Electrode arrangement for tests on casting and moulding materials
(diameter of the spherical electrodes: d = (20 ± 0,1) mm) . 21
Figure 5 – Electrode arrangement for test on shaped insulating parts (see 5.2.7) . 21
Figure 6 – Electrode arrangement for tests parallel to the surface (and along the
laminae, if present) . 22
Figure 7 – Electrode arrangement for tests parallel to the surface (and along the
laminae if present) . 23
Figure 8 – Arrangement for tests parallel to the laminae for boards more than 15 mm
thick with parallel cylindrical electrodes (see 5.3.4) . 24

Table 1 – Increments of voltage increase (kilovolts, peak / ) . 16
2

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SIST EN 60243-1:2013
– 4 – 60243-1 © IEC:2013
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________

ELECTRIC STRENGTH OF INSULATING MATERIALS –
TEST METHODS –

Part 1: Tests at power frequencies

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 60243-1 has been prepared by technical committee 112:
Evaluation and qualification of electrical insulating materials and systems.
This third edition cancels and replaces the second edition, published in 1998, and constitutes
a technical revision.
The significant technical change with respect to the previous edition is that the current version
now includes an option for testing elastomeric materials.
The text of this standard is based on the following documents:
FDIS Report on voting
112/237/FDIS 112/248/RVD

Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.

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SIST EN 60243-1:2013
60243-1 © IEC:2013 – 5 –
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all the parts in the IEC 60243 series, published under the general title Electric
strength of insulating materials – Test methods, can be found on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.

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SIST EN 60243-1:2013
– 6 – 60243-1 © IEC:2013
ELECTRIC STRENGTH OF INSULATING MATERIALS –
TEST METHODS –

Part 1: Tests at power frequencies



1 Scope
This part of IEC 60243 provides test methods for the determination of short-time electric
strength of solid insulating materials at power frequencies between 48 Hz and 62 Hz.
This standard does not cover the testing of liquids and gases, although these are specified
and used as impregnates or surrounding media for the solid insulating materials being tested.
NOTE Methods for the determination of breakdown voltages along the surfaces of solid insulating materials are
included.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and
are indispensable for its application. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 60212, Standard conditions for use prior to and during the testing of solid electical
insulating materials
IEC 60296, Fluids for electrotechnical applications – Unused mineral insulating oils for
transformers and switchgear
IEC 60455-2, Specification for solventless polymerizable resinous compounds used for
electrical insulation – Part 2: Methods of test
IEC 60464-2, Varnishes used for electrical insulation – Part 2: Methods of test
IEC 60684-2, Flexible insulating sleeving – Part 2: Methods of test
IEC 60836, Specifications for unused silicone insulating liquids for electrotechnical purposes
IEC 61099, Insulating liquids – Specifications for unused synthetic organic esters for electrical
purposes
ISO 293, Plastics – Compression moulding of test specimens of thermoplastic materials
ISO 294-1, Plastics – Injection moulding of test specimens of thermoplastic materials – Part 1:
General principles, and moulding of multipurpose and bar test specimens
ISO 294-3, Plastics – Injection moulding of test specimens of thermoplastic materials – Part 3:
Small plates
ISO 295, Plastics – Compression moulding of test specimens of thermosetting materials

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SIST EN 60243-1:2013
60243-1 © IEC:2013 – 7 –
ISO 10724 (all parts), Plastics – Injection moulding of test specimens of thermosetting powder
moulding compounds (PMCs)
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
electric breakdown
severe loss of the insulating properties of test specimens while exposed to electric stress,
which causes the current in the test circuit to operate an appropriate circuit-breaker
Note 1 to entry: Breakdown is often caused by partial discharges in the gas or liquid medium surrounding the test
specimen and the electrodes which puncture the specimen beyond the periphery of the smaller electrode (or of
both electrodes, if of equal diameter).
3.2
flashover
loss of the insulating properties of the gas or liquid medium surrounding a test specimen and
electrodes while exposed to electric stress, which causes the current in the test circuit to
operate an appropriate circuit-breaker
Note 1 to entry: The presence of carbonized channels or punctures through the specimen distinguishes tests
where breakdown occurred, from others where flashover occurred.
3.3
breakdown voltage
3.3.1
< tests with continuously rising voltage > voltage at which a specimen suffers breakdown
under the prescribed test conditions
3.3.2
< step-by-step tests > highest voltage which a specimen withstands without breakdown for the
duration of the time at that voltage level
3.4
electric strength
quotient of the breakdown voltage and the distance between the electrodes between which
the voltage is applied under the prescribed test conditions
Note 1 to entry: The distance between the test electrodes is determined as specified in 5.5, unless otherwise
specified.
4 Significance of the test
Electric strength test results obtained in accordance with this standard are useful for detecting
changes or deviations from normal characteristics resulting from processing variables, ageing
conditions or other manufacturing or environmental situations. However, they are not intended for
use in evaluating the behaviour of insulating materials in an actual application.
Measured values of the electric strength of a material may be affected by many factors,
including:
a) Condition of test specimens
1) the thickness and homogeneity of the specimen and the presence of mechanical strain;
2) previous conditioning of the specimens, in particular drying and impregnation
procedures;

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SIST EN 60243-1:2013
– 8 – 60243-1 © IEC:2013
3) the presence of gaseous inclusions, moisture or other contamination.
b) Test conditions
1) the frequency, waveform and rate of rise or time of application of the voltage;
2) the ambient temperature, pressure and humidity;
3) the configuration, the dimensions, and thermal conductivity of the test electrodes;
4) the electrical and thermal characteristics of the surrounding medium.
The effects of all these factors shall be considered when investigating materials for which no
experience exists. This standard defines particular conditions which give rapid discrimination
between materials and which can be used for quality control and similar purposes.
The results given by different methods are not directly comparable but each may provide
information on relative electric strengths of materials. The electric strength of most materials
decreases as the thickness of the specimen between the electrodes increases and as the time
of voltage application increases.
The measured electric strength of most materials is significantly affected by the intensity and
the duration of surface discharges prior to breakdown. For designs which are free from partial
discharges up to the test voltage, it is very important to know the electric strength without
discharges prior to breakdown. However, the methods in this standard are generally not
suitable for providing this information.
Materials with high electric strength will not necessarily resist long-term degradation
processes such as heat, erosion or chemical deterioration by partial discharges, or
electrochemical deterioration in the presence of moisture, all of which may cause failure in
service at much lower stress.
5 Electrodes and specimens
5.1 General
The metal electrodes shall be maintained smooth, clean and free from defects at all times.
Electrode arrangements for tests on boards and sheets perpendicular to the surface are
shown in Figure 1.
NOTE This maintenance becomes more important when thin specimens are being tested. Stainless steel
electrodes e.g. minimize electrode damage at breakdown.
The leads to the electrodes shall not tilt or otherwise move the electrodes, nor affect the
pressure on the specimen, nor appreciably affect the electric field configuration in the
neighbourhood of the specimen.
When very thin films (for example <5 μm thick) are to be tested, the standards for those
materials shall specify the electrodes and special procedures for handling and specimen
preparation.
5.2 Tests perpendicular to the surface of non-laminated materials and normal to
laminate of laminated materials
5.2.1 Boards and sheet materials, including pressboards, papers, fabrics and films
5.2.1.1 Unequal electrodes
The electrodes shall consist of two metal cylinders with the edges rounded to give a radius of
(3 ± 0,2) mm. One electrode shall be (25 ± 1) mm in diameter and approximately 25 mm high.
The other electrode shall be (75 ± 1) mm in diameter and approximately 15 mm high. These
two electrodes shall be arranged coaxially within 2 mm as in Figure 1a.

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SIST EN 60243-1:2013
60243-1 © IEC:2013 – 9 –
NOTE Radii for surface not in contact with the electrode are not critical with respect to test results but should
avoid partial discharges in the surrounding medium.
5.2.1.2 Equal diameter electrodes
If a fixture is employed, which accurately aligns upper and lower electrodes within 1,0 mm,
the diameter of the lower electrode may be reduced to (25 ± 1) mm, the diameters of the two
electrodes differing by no more than 0,2 mm. The results obtained will not necessarily be the
same as those obtained with the unequal electrodes of 5.2.1.1.
5.2.1.3 Sphere and plate electrodes
The electrodes shall consist of a metal sphere and a metal plate (see Figure 1c). The upper
electrode shall be a sphere of (20 ± 1) mm in diameter and the lower one is a metal plate of
(25 ± 1) mm in diameter with the edge rounded to give a radius of 2.5 mm. The discrepancy of
the central axes between upper and lower electrodes shall be within 1 mm.
5.2.1.4 Tests on thick sample
When specified, boards and sheets over 3 mm thick shall be reduced by machining on one
side to (3 ± 0,2) mm and then tested with the high-potential electrode on the non-machined
surface.
When it is necessary in order to avoid flashover or because of limitations of
...