IEC 60626-2:2009

IEC 60626-2 ®
Edition 3.0 2009-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Combined flexible materials for electrical insulation –
Part 2: Methods of test
Matériaux combinés souples destinés à l'isolement électrique –
Partie 2: Méthodes d'essai
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IEC 60626-2 ®
Edition 3.0 2009-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Combined flexible materials for electrical insulation –
Part 2: Methods of test
Matériaux combinés souples destinés à l'isolement électrique –
Partie 2: Méthodes d'essai
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
K
CODE PRIX
ICS 17.220.99; 29.035.01 ISBN 978-2-88910-237-2
– 2 – 60626-2 © IEC:2009
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
COMBINED FLEXIBLE MATERIALS
FOR ELECTRICAL INSULATION –
Part 2: Methods of test
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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with the International Organization for Standardization (ISO) in accordance with conditions determined by
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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 60626-2 has been prepared by IEC technical committee 15: Solid
electrical insulating materials.
This third edition cancels and replaces the second edition published in 1995 and constitutes a
major technical revision. The main changes from the previous edition are as follows: some
tests such as for edge tearing and stiffness, actually not used and not listed in the
requirements of Part 3, were deleted.

60626-2 © IEC:2009 – 3 –
The text of this standard is based on the following documents:
CDV Report on voting
15/470/CDV 15/512/RVC
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all the parts in the IEC 60626 series, under the general title Combined flexible
materials for electrical insulation, can be found on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until
the maintenance result 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.
– 4 – 60626-2 © IEC:2009
INTRODUCTION
This International standard deals with test methods of combined flexible materials consisting
of two or more different insulating materials laminated together as described in IEC 60626-1.
The components of flexible combined materials are polymer film and fibrous sheet material.
This standard does not include materials based on mica paper, as primary component,
covered by IEC 60371, but mica paper may be used as complementary material.
The series has three parts describing:
Part 1: Definitions and general requirements (IEC 60626-1)
Part 2: Methods of test (IEC 60626-2)
Part 3: Specifications for individual materials (IEC 60626-3)

60626-2 © IEC:2009 – 5 –
COMBINED FLEXIBLE MATERIALS
FOR ELECTRICAL INSULATION –
Part 2: Methods of test
1 Scope
This International Standard provides the test methods for combined flexible materials for
electrical insulation. Some properties and relevant test methods, according to the perfomance
requirements of IEC 60626-3, were confirmed. Other test methods are described as a
supplement of guidance for further specification that could be agreed between customer and
supplier to meet specific needs of the end use.
Materials which conform to this specification meet established levels of performance.
However, the selection of material by a user for a specific application should be based on the
actual requirements necessary for adequate performance in that application and not based on
this specification alone.
SAFETY WARNING
It is the responsibility of the user of the methods contained or referred to in this document to
ensure that they are used in a safe manner.
2 Normative references
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.
IEC 60216-4-1:2006, Electrical insulating materials – Thermal endurance properties – Part 4:
Ageing ovens – Section 1: Single-chamber ovens
IEC 60243-1:1998, Electrical strength of insulating materials – Test methods – Part 1: Tests
at power frequencies
IEC 60626-3:2008, Combined flexible materials for electrical insulation –
Part 3: Specifications for individual materials
ISO 536: 1995, Paper and board – Determination of grammage
3 General requirements on tests
Unless otherwise specified, the test specimens, after being cut, shall be conditioned for 24 h
at (23 ± 2) °C and (50 ± 5) % relative humidity. If the test is not conducted in this standard
atmosphere, the test shall be made within 5 min after removal from the standard atmosphere.

– 6 – 60626-2 © IEC:2009
4 Thickness
4.1 Test apparatus
4.1.1 An external screw type micrometer having measuring faces of 6 mm to 8 mm diameter.
The measuring faces shall be flat to within 0,001 mm and parallel to within 0,003 mm. The
pitch of the screw shall be 0,5 mm and the graduations shall be 50 divisions of 0,01 mm,
enabling readings to be estimated to 0,002 mm.
The pressure exerted on the specimens shall be 100 kPa as described in 4.1.2.
4.1.2 A dead-weight dial type micrometer having two ground and lapped concentric circular
surfaces flat to within 0,001 mm and parallel to within 0,003 mm. The upper surface shall be 6
mm to 8 mm in diameter. The lower surface shall be larger than the upper one. The upper
surface shall move on the axis perpendicular to the surfaces. The dial shall be graduated to
read directly to 0,002 mm. The frame of the micrometer shall be of such rigidity that a force of
15 N applied to dial housing, out of contact with either the weight or the presser foot spindle,
will produce a deflection of the frame not greater than 0,002 mm as indicated on the
micrometer dial. The pressure exerted on the specimen shall be 100 kPa.
4.1.3 The setting gauge used to check the instruments shall be accurate to within
±0,001 mm of the nominal size. The indicated thickness by the instruments shall not differ
by more than 0,005 mm from the gauge block.
NOTE For materials with high compressibility and special structure, other values for the area and the pressure of
the measuring faces may be specified.
4.2 Test specimens
4.2.1 General
In the "as received" condition.
4.2.2 Full width and sheet material
Full width material delivered on rolls or sheet material cut to length. One specimen 25 mm
wide and whose length is equal to the width of the roll or sheet shall be cut across the entire
width of the material.
4.2.3 Slit material (tape)
One specimen 1 m long shall be cut from the roll.
4.3 Procedure
Measu
...