EN 60426:2007

SLOVENSKI STANDARD
01-december-2007
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Electrical insulating materials - Determination of electrolytic corrosion caused by
insulating materials - Test methods (IEC 60426:2007)
Elektroisolierstoffe - Prüfungen zur Bestimmung der elektrolytischen Korrosionswirkung
von Isoliermaterialien (IEC 60426:2007)
Matériaux isolants électriques - Détermination de la corrosion électrolytique en présence
de matériaux isolants - Méthodes d'essais (IEC 60426:2007)
Ta slovenski standard je istoveten z: EN 60426:2007
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
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN 60426
NORME EUROPÉENNE
February 2007
EUROPÄISCHE NORM
ICS 17.220.99; 29.035.01
English version
Electrical insulating materials -
Determination of electrolytic corrosion caused by insulating materials -
Test methods
(IEC 60426:2007)
Matériaux isolants électriques -  Elektroisolierstoffe -
Détermination de la corrosion Prüfungen zur Bestimmung
électrolytique en présence der elektrolytischen Korrosionswirkung
de matériaux isolants - von Isoliermaterialien
Méthodes d'essais (IEC 60426:2007)
(CEI 60426:2007)
This European Standard was approved by CENELEC on 2007-02-01. 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 Central Secretariat 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 Central Secretariat has the same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Cyprus, the
Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland and the United Kingdom.

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

Central Secretariat: rue de Stassart 35, B - 1050 Brussels

© 2007 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 60426:2007 E
Foreword
The text of document 112/45/FDIS, future edition 2 of IEC 60426, prepared by IEC TC 112, Evaluation
and qualification of electrical insulating materials and systems, was submitted to the IEC-CENELEC
parallel vote and was approved by CENELEC as EN 60426 on 2007-02-01.
The following dates were fixed:
– latest date by which the EN has to be implemented
at national level by publication of an identical
national standard or by endorsement (dop) 2007-11-01
– latest date by which the national standards conflicting
with the EN have to be withdrawn (dow) 2010-02-01
Annex ZA has been added by CENELEC.
__________
Endorsement notice
The text of the International Standard IEC 60426:2007 was approved by CENELEC as a European
Standard without any modification.
__________
- 3 - EN 60426:2007
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications

The following referenced documents are indispensable for the application 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  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 60068-3-4 2001 Environmental testing – EN 60068-3-4 2002
Part 3-4: Supporting documentation and
guidance - Damp heat tests
1)
IEC 60454-2 - Specifications for pressure-sensitive adhesive - -
tapes for electrical purposes –
Part 2: Methods of test
1)
At draft stage.
INTERNATIONAL IEC
STANDARD 60426
Second edition
2007-01
Electrical insulating materials –
Determination of electrolytic corrosion
caused by insulating materials –
Test methods
© IEC 2007 ⎯ Copyright - all rights reserved
No part of this publication may be reproduced or utilized in any form or by any means, electronic or
mechanical, including photocopying and microfilm, without permission in writing from the publisher.
International Electrotechnical Commission, 3, rue de Varembé, PO Box 131, CH-1211 Geneva 20, Switzerland
Telephone: +41 22 919 02 11 Telefax: +41 22 919 03 00 E-mail: inmail@iec.ch Web: www.iec.ch
PRICE CODE
Commission Electrotechnique Internationale U
International Electrotechnical Commission
МеждународнаяЭлектротехническаяКомиссия
For price, see current catalogue

– 2 – 60426 © IEC:2007(E)
CONTENTS
FOREWORD.4
INTRODUCTION.6

1 Scope.7
2 Normative references .7
3 Terms and definitions .7
4 General description of the test method .8
5 Test specimens .8
5.1 General .8
5.2 Cut surfaces of rigid materials (blocks, plates, sheets or semi-finished
materials) .9
5.3 Cast, moulding, injection and pressed materials .9
5.4 Cut surfaces of flexible films, foils and thin sheets.9
5.5 Adhesive tapes.10
5.6 Flexible sleeving and tubing .10
5.7 Lacquers and insulating varnishes.10
5.8 Cleanliness of contact surfaces .10
5.9 Number of test specimens .11
6 Test strips .11
6.1 General .11
6.2 Preparation of the test strips .11
6.3 Cleanliness of test strips .12
7 Test device.12
8 Test conditions .14
9 Test procedure .14
10 Evaluation .14
10.1 General evaluation .14
10.2 Visual inspection of the test strips .15
10.3 Tensile strength of test strips .15
11 Evaluation of corrosion on copper strips .16
12 Test report.17

Annex A (normative)  Tables for the evaluation of corrosion on brass and aluminium
strips .18
Annex B (informative) Notes on visual evaluation .20
Annex C (informative) Copper wire tensile strength method .21

Figure 1 – Test specimen of rigid material, for example textile laminate.8
Figure 2 – Test specimen of flexible material, for example flexible films, foils etc.10
Figure 3 – Test strip.12
Figure 4 – Test device for determining electrolytic corrosion.13
Figure C.1 – Apparatus for determining electrolytic corrosion of rigid insulating material .23
Figure C.2 – Apparatus for determining electrolytic corrosion of flexible insulating material .23

60426 © IEC:2007(E) – 3 –
Table 1 – Degrees of corrosion of copper strips .16
Table A.1 – Degrees of corrosion of brass strips.18
Table A.2 – Degrees of corrosion of aluminium strips .19

– 4 – 60426 © IEC:2007(E)
INTERNATIONAL ELECTROTECHNICAL COMMISSION
___________
ELECTRICAL INSULATING MATERIALS −

DETERMINATION OF ELECTROLYTIC CORROSION CAUSED BY
INSULATING MATERIALS −
TEST METHODS
FOREWORD
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International Standard IEC 60426 has been prepared by IEC technical committee 112:
Evaluation and qualification of electrical insulating materials and systems.
This second edition cancels and replaces the first edition, published in 1973, and constitutes
a technical revision.
The main changes with respect to the previous edition are listed below:
...