EN 60626-2:1995
(Main)Combined flexible materials for electrical insulation - Part 2: Methods of test
Combined flexible materials for electrical insulation - Part 2: Methods of test
Deals with the tests applicable to combined materials constituted by plastic films and/or fibrous materials such as papers, woven or non-woven fabrics, impregnated or not impregnated
Flexible Mehrschichtisolierstoffe zur elektrischen Isolation - Teil 2: Prüfverfahren
Matériaux combinés souples destinés à l'isolement électrique - Partie 2: Méthodes d'essai
Traite des essais applicables aux matériaux combinés constitués par des films de matière plastique et pour des matériaux fibreux tels que les papiers, les lissés et les non-lissés, imprégnés ou non.
Combined flexible materials for electrical insulation - Part 2: Methods of test (IEC 60626-2:1995
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
01-junij-1998
Combined flexible materials for electrical insulation - Part 2: Methods of test (IEC
60626-2:1995
Combined flexible materials for electrical insulation -- Part 2: Methods of test
Flexible Mehrschichtisolierstoffe zur elektrischen Isolation -- Teil 2: Prüfverfahren
Matériaux combinés souples destinés à l'isolement électrique -- Partie 2: Méthodes
d'essai
Ta slovenski standard je istoveten z: EN 60626-2:1995
ICS:
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.
NORME
CEI
INTERNATIONALE IEC
626-2
INTERNATIONAL
Deuxième édition
STANDARD
Second edition
1995-09
Matériaux combinés souples destinés
à l'isolement électrique —
Partie 2:
Méthodes d'essai
Combined flexible materials for electrical
insulation —
Part 2:
Methods of test
Copyright — all rights reserved
© CEI 1995 Droits de reproduction réservés —
of this publication may be reproduced or utilized in
Aucune partie de cette publication ne peut être reproduite ni No part
any form or by any means, electronic or mechanical,
utilisée sous quelque forme que ce soit et par aucun pro-
including photocopying and microfilm, without permission
cédé, électronique ou mécanique, y compris la photocopie et
in writing from the publisher.
les microfilms, sans l'accord écrit de l'éditeur.
Genève, Suisse
Bureau Central de la Commission Electrotechnique Internationale 3, rue de Varembé
Commission Electrotechnique Internationale CODE PRIX
International Electrotechnical Commission
PRICE CODE
IEC MetttuyHapoaHaa 3netsrporexHHgecKaa lioMKccIR
vigueur
Pour prix, voir catalogue en •
•
For price, see current catalogue
626-2 © IEC:1995 - 3 -
INTERNATIONAL ELECTROTECHNICAL COMMISSION
COMBINED FLEXIBLE MATERIALS
FOR ELECTRICAL INSULATION —
Part 2: Methods of test
FOREWORD
1) The IEC (International Electrotechnical Commission) is a worldwide organization for standardization
comprising all national electrotechnical committees (IEC National Committees). The object of the IEC is to
promote international cooperation on all questions concerning standardization in the electrical and
electronic fields. To this end and in addition to other activities, the IEC publishes International Standards.
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. The 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 the IEC on technical matters, prepared by technical committees on
which all the National Committees having a special interest therein are represented, express, as nearly as
possible, an international consensus of opinion on the subjects dealt with.
3) They have the form of recommendations for international use published in the form of standards, technical
reports or guides and they are accepted by the National Committees in that sense.
4) In order to promote international unification, IEC National Committees undertake to apply IEC International
Standards transparently to the maximum extent possible in their national and regional standards. Any
divergence between the IEC Standard and the corresponding national or regional standard shall be clearly
indicated in the latter.
International Standard IEC 626-2 has been prepared by sub-committee 15C: Specifications,
of IEC technical committee 15: Insulating materials.
This second edition cancels and replaces the first edition published in 1978 and consti-
tutes a technical revision.
The text of this standard is based on the following documents:
DIS Report on voting
15C/478/DIS 15C/566/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.
626-2 © IEC:1995 - 5 -
INTRODUCTION
This International standard is one of a series which deals with combined flexible materials
consisting of two or more different insulating materials laminated together. The
components of flexible combined materials are polymer film and fibrous sheet material.
Typical fibrous sheet materials include, but are not limited to: dry-laid non-woven, wet-laid
non-woven (e.g., paper), and woven fabric. The non-woven may or may not be treated by
mechanical, chemical, hydraulic or thermal processing to alter characteristics. The fibrous
material may or may not be impregnated with a resin. This standard does not include
materials based on mica paper, neither does it deal with combined materials in which one
of the components is deliberately left in the B-stage. The series has three parts
describing:
Part 1: Definitions and general requirements (IEC 626-1)
Part 2: Methods of test (IEC 626-2)
Part 3: Specifications for individual materials (IEC 626-3)
626-2 © IEC:1995 – 7 –
COMBINED FLEXIBLE MATERIALS
FOR ELECTRICAL INSULATION —
Part 2: Methods of test
1 General
1.1 Scope
This International Standard states the requirement relating to the test methods for
combined flexible materials for electrical insulation.
1.2 Normative references
The following normative documents contain provisions which, through reference in this
text, constitute provisions of this part of IEC 626. At the time of publication, the editions
indicated were valid. All normative documents are subject to revision, and pa rties to
rt of IEC 626 are encouraged to investigate the possibility of
agreements based on this pa
applying the most recent editions of the normative documents indicated below. Members
of IEC and ISO maintain registers of currently valid International Standards. In the event
of dispute, the referenced editions shall be used.
Guide for the determination of thermal endurance properties of
IEC 216-4-1:1990,
electrical insulating materials - Part 4: Ageing ovens – Section 1: Single chamber
IEC 243-1:1988, Methods of test for electric strength of solid insulating materials – Part 1:
Tests at power frequencies
Specification for combined flexible materials for electrical insulation –
IEC 626-3:1988,
Part 3: Specifications for individual materials
Paper and board – Determination of grammage
ISO 536:1986,
General requirements on tests
1.3
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.
2 Thickness
2.1
Test apparatus
2.1.1 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.
- 9 -
626-2 © IEC:1995
The pressure exerted on the specimens shall be 100 kPa as described in 2.1.2.
2.1.2 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.
2.1.3 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.
2.2
Test specimens
In the "as received" condition.
2.2.1 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.
2.2.2 Slit material (tape)
One specimen 1 m long shall be cut from the roll.
2.3 Procedure
Measure the thickness of the material, when not constrained in any way, at nine points
spaced not less than 75 mm apart along the length of the test specimens. All joins (or
splices) shall be excluded from the area of the test.
2.4
Results
The values of the nine measurements shall be recorded. The central value is taken as the
thickness of the material.
3 Substance (weight per unit area or grammage)
Because of the electrical engineering practice of using the word substance, this has been
used here. The substance of combined materials shall be measured in accordance with
the method described in ISO 536, with the following exceptions:
- clauses 5 and 6 of ISO 536 are ignored;
– 11 –
626-2 ©IEC:1995
the test shall be carried out on three specimens in the "as received" condition;
–
determine the mass with an accuracy of 0,5 % on specimens of not less than
–
100 cm2;
the central value is taken as the result, the two others are reported.
–
4 Tensile strength and elongation
4.1 Test apparatus
Either a constant rate-of-loading machine or a constant rate-of-traverse machine may be
used. The machine preferably shall be power driven and graduated so that a reading of
1 % of the value required by the specification sheet is possible.
4.2 Test specimens
Five specimens are used. The length of the test specimens shall be such that it allows
a length of 200 mm between the jaws of the testing machine. When testing full width
material, the width shall be 15 mm, five test specimens shall be cut in the machine
direction, and five test specimens perpendicular to that direction. When testing specimens
containing woven fabric, the test specimens shall be cut so that no two test specimens cut
in the same direction contain the same longitudinal threads.
Slit material (tape) is tested in the "as-delivered" width up to a maximum 30 mm.
Procedure for unfolded specimens
4.3
Fix a test specimen in the testing machine and apply the load in such a way that the time
from the commencement of the application of the load to the moment at which the load
corresponding to the specified minimum tensile strength is reached is (60 ± 10) s;
continue until one of the components of the specimen breaks. Record the breaking force
and, if required, the elongation.
If the test specimen breaks in or at the clamps of the testing machine, discard the result
and make a further test using another test specimen.
When the tensile strength of a join is to be determined, the position of the join shall be
approximately midway between the clamps.
NOTE — With certain materials, extra precautions may be required to prevent slipping.
Procedure for folded specimens
4.4
The specimens are bent over by hand in the middle of their lengths and at right angles to
the longitudinal edges of the specimens. They are then fed through the rollers of the
folding apparatus illustrated in figure 1 in the longitudinal direction of the specimen, the
longitudinal edge of the specimen lying against the guide. After unfolding, the specimen is
tested according to 4.3.
626-2 © IEC:1995 - 13 -
4.5 Results
Tensile strength
Take the central value of the five loads at break and calculate the tensile strength of the
material expressed in newtons per 10 mm of width.
Elongation at break
Take the central value of the five values as the elongation at break of the first component
which breaks, expressed in per cent of the specimen length between the clamps.
5 Delamination
Before being subjected to the tensile test, the specimen produced according to 4.4 shall
be examined visually for delamination and other effects.
6 Edge tearing resistance
6.1 Apparatus
An edge tear stirrup (see figure 2) shall be used, attached to the tensile testing apparatus
as described in clause 4. The edge tear stirrup consists of a thin steel plate (A) which
forms a horizontal beam supported on edge by the ends of a stirrup-shaped frame.
The thin metal tang of the stirrup frame is fastened in the lower clamp of the tensile testing
machine so that the ve rtical center line of the stirrup coincides with the line connecting the
mid-points of the upper and lower clamps. The horizontal beam is removable from the stir-
rup frame and two beams are provided for use with materials of different thickness ranges.
One beam has thickness of (1,25 ± 0,05) mm and the other a thickness of
(2,50 ± 0,05) mm. The edge of the beam forms a shallow V-notch, the sides of which
subtend a (150 ± 1)° angle. The sides of the V-notch are semi-circular in cross-section
and shall be smooth and straight.
6.2 Test specimens
Prepare nine test specimens having dimensions 250 mm length and 15 mm to 25 mm
width such that the 250 mm dimension is parallel to the machine direction of the material.
rt the results on these specimens as
Label these specimens as MD specimens. Repo
MD edge tear resistance. Prepare nine additional specimens with the machine direction
parallel to the 15 mm to 25 mm dimension. Label these specimens as CD specimens.
Report the results on these specimens as CD tear resistance. Condition all specimens in
accordance with clause 1.3.
626-2 © IEC:1995 -15 -
6.3 Procedure
Attach a beam of the proper thickness to the stirrup frame. The bar with the
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.