IEC 60811-401:2012

IEC 60811-401 ®
Edition 1.1 2017-07
CONSOLIDATED VERSION
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Electric and optical fibre cables – Test methods for non-metallic materials –
Part 401: Miscellaneous tests – Thermal ageing methods – Ageing in an air oven

Câbles électriques et à fibres optiques – Méthodes d’essai pour les matériaux
non-métalliques –
Partie 401: Essais divers – Méthodes de vieillissement thermique –
Vieillissement en étuve à air
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IEC 60811-401 ®
Edition 1.1 2017-07
CONSOLIDATED VERSION
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Electric and optical fibre cables – Test methods for non-metallic materials –

Part 401: Miscellaneous tests – Thermal ageing methods – Ageing in an air oven

Câbles électriques et à fibres optiques – Méthodes d’essai pour les matériaux

non-métalliques –
Partie 401: Essais divers – Méthodes de vieillissement thermique –

Vieillissement en étuve à air
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.035.01; 29.060.20 ISBN 978-2-8322-4652-8

IEC 60811-401 ®
Edition 1.1 2017-07
CONSOLIDATED VERSION
REDLINE VERSION
VERSION REDLINE
colour
inside
Electric and optical fibre cables – Test methods for non-metallic materials –
Part 401: Miscellaneous tests – Thermal ageing methods – Ageing in an air oven

Câbles électriques et à fibres optiques – Méthodes d’essai pour les matériaux
non-métalliques –
Partie 401: Essais divers – Méthodes de vieillissement thermique –
Vieillissement en étuve à air
– 2 – IEC 60811-401:2012+AMD1:2017 CSV
 IEC 2017
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 Test method . 6
4.1 General . 6
4.2 Influence of the ageing treatment on the mechanical characteristics . 7
4.2.1 Apparatus . 7
4.2.2 Sample and test pieces preparation . 7
4.2.3 Ageing procedure . 7
4.2.4 Measurements . 8
4.2.5 Expression of results . 8
4.2.6 Requirements . 9
4.2.7 Test report . 9
4.3 Bending test on test pieces of core . 9
4.3.1 Apparatus . 9
4.3.2 Sample and test pieces preparation . 9
4.3.3 Procedure . 9
4.3.4 Requirement . 10
4.3.5 Test report . 10
Annex A (normative) Methods of measuring air flow in ovens . 11
Annex B (normative) Test pieces preparation in presence of copper or metal coated
copper conductor . 15
Annex C (normative) Sample and test pieces preparation for ageing of complete cable . 18
Bibliography . 19

Figure A.1 – Flowmeter for air-flow control in air ovens for method 2 . 13
Figure A.2 – Calibration diagram of the capillary tube of the flowmeter for air-flow
control in air ovens for method 2 . 14
Figure B.1 – Specially prepared test pieces . 17
Figure B.2 – Dumb-bell test pieces preparation after ageing . 17

Table 1 – Number of turns for bending test . 10
Table B.1 – Summary of ageing tests for insulated conductors in case of difficulties in
preparing test pieces due to conductor insulation or separator adhesion during ageing . 15

 IEC 2017
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ELECTRIC AND OPTICAL FIBRE CABLES –
TEST METHODS FOR NON-METALLIC MATERIALS –
Part 401: Miscellaneous tests –
Thermal ageing methods – Ageing in an air oven
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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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.
This consolidated version of the official IEC Standard and its amendment has been prepared
for user convenience.
IEC 60811-401 edition 1.1 contains the first edition (2012-03) [documents 20/1285/FDIS and
20/1334/RVD] and its amendment 1 (2017-07) [documents 20/1733/FDIS and 20/1738/RVD].
In this Redline version, a vertical line in the margin shows where the technical content is
modified by amendment 1. Additions are in green text, deletions are in strikethrough red text. A
separate Final version with all changes accepted is available in this publication.

– 4 – IEC 60811-401:2012+AMD1:2017 CSV
 IEC 2017
International Standard IEC 60811-401 has been prepared by IEC technical committee 20:
Electric cables.
There are no specific technical changes with respect to the previous edition, but see
the Foreword to IEC 60811-100:2012.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
This part of IEC 60811 shall be used in conjunction with IEC 60811-100.
A list of all the parts in the IEC 60811 series, published under the general title Electric and
optical fibre cables – Test methods for non-metallic materials, can be found on the IEC
website.
The committee has decided that the contents of the base publication and its amendment 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.
IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct
understanding of its contents. Users should therefore print this document using a
colour printer.
 IEC 2017
INTRODUCTION
The IEC 60811 series specifies the test methods to be used for testing non-metallic materials
of all types of cables. These test methods are intended to be referenced in standards for
cable construction and for cable materials.
NOTE 1 Non-metallic materials are typically used for insulating, sheathing, bedding, filling or taping within cables.
NOTE 2 These test methods are accepted as basic and fundamental and have been developed and used over
many years principally for the materials in all energy cables. They have also been widely accepted and used for
other cables, in particular optical fibre cables, communication and control cables and cables for ships and offshore
applications.
– 6 – IEC 60811-401:2012+AMD1:2017 CSV
 IEC 2017
ELECTRIC AND OPTICAL FIBRE CABLES –
TEST METHODS FOR NON-METALLIC MATERIALS –

Part 401: Miscellaneous tests –
Thermal ageing methods – Ageing in an air oven

1 Scope
This Part 401 of IEC 60811 specifies the procedure for ageing in an air oven, which typically
applies to crosslinked and thermoplastic compounds used for insulating and sheathing
materials.
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 60228, Conductors of insulated cables
IEC 60811-100:2012, Electric and optical fibre cables – Test methods for non-metallic

materials – Part 100: General
IEC 60811-409, Electric and optical fibre cables – Test methods for non-metallic materials –
Part 409: Miscellaneous tests – Loss of mass test for thermoplastic insulations and sheaths
IEC 60811-501, Electric and optical fibre cables – Test methods for non-metallic materials –
Part 501: Mechanical tests – Tests for determining the mechanical properties of insulating and
sheathing compounds
IEC 60811-504, Electric and optical fibre cables – Test methods for non-metallic materials –
Part 504: Mechanical tests – Bending tests at low temperature for insulation and sheaths
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60811-100 apply.
4 Test method
4.1 General
This part of IEC 60811 shall be used in conjunction with IEC 60811-100.
Unless otherwise specified, tests shall be carried out at room temperature.
An ageing treatment in an air oven may be required by the relevant cable standard:
a) for prepared test pieces of insulating or sheathing material only (see 4.2.3.2);
b) for prepared test pieces of cores (conductor and insulation) (see 4.2.3.2 and 4.2.3.3 if
necessary);
 IEC 2017
c) for test pieces of completed cable (see 4.2.3.4);
d) for the loss of mass test (see IEC 60811-409).
The ageing test a) or b) and the loss of mass test d) may be combined and carried out on the
same test pieces when the aging time and aging temperature are the same.
In general, mechanical characteristics are measured after treatment, but in some cases, the
conductor and the separator, if any, cannot be removed without damaging the insulation and a
bending test is realized on the circular conductor up to and including 16 mm . Ageing followed
by the bending test is considered the acceptance procedure in case of dispute.
4.2 Influence of the ageing treatment on the mechanical characteristics
4.2.1 Apparatus
The ageing treatment is realized in an oven with natural air flow or air flow by pressure. The
air shall enter the oven in such a way that it flows over the surface of the test pieces and
leaves near the top of the oven. The oven shall have not less than 8 and not more than 20
complete air changes per hour at the specified ageing temperature. Two test methods for
measuring air flow through an oven are given in Annex A.
Unless otherwise specified in the relevant cable specification, a rotating fan inside the oven is
allowed when testing rubber compounds. For all other compounds a fan shall not be used
inside the oven, and in cases of dispute, rubber compounds shall also be tested in an oven
which is designed to operate without a fan rotating inside it.
4.2.2 Sample and test pieces preparation
The sample of the cable, or sheath removed from the cable, or samples of core, cut into
pieces which are sufficiently long, shall be taken, preferably from positions close to that from
which the samples for the tensile tests without ageing are taken in accordance with
IEC 60811-501.
Test pieces, dumb-bell or tubular, are prepared according to IEC 60811-501.
Test pieces can consist of samples of core, cut into pieces which are sufficiently long. If, after
ageing, the conductor and the separator, if any, cannot be removed without damaging the
insulation, preparation of test pieces shall be carried out according to Annex B (Clause B.2).
For circular conductors up to and including 16 mm and having plain or metal coated wires
and also when a separator around the conductor is included, a bending test is carried out on
the aged test pieces.
4.2.3 Ageing procedure
4.2.3.1 General
This test shall be carried out not less than 16 h after the extrusion or cross-linking, if any, of
the insulating or sheathing compounds. It can be done on tubular or dumb-bell test pieces
prepared according to IEC 60811-501 or insulated cores as described in the present standard.
4.2.3.2 Ageing procedure for test pieces prepared according to IEC 60811-501 and
Clause B.1 and B.2.2 and Annex C of this standard
This procedure shall be used for
– test pieces of insulating material without conductor and of sheathing material, according to
IEC 60811-501,
– test pieces of cores with the original conductor (see Clause B.1),
– tubular test pieces with a reduced conductor (see B.2.2),

– 8 – IEC 60811-401:2012+AMD1:2017 CSV
 IEC 2017
– complete cable (see Annex C).
Compounds of obviously different compositions shall not be tested at the same time in the
same oven.
Five test pieces, as specified in IEC 60811-501 shall be suspended vertically and
substantially in the middle of the oven so that each test piece is at least 20 mm from any
other test pieces.
The test pieces shall not occupy more than 2 % of the volume of the oven.
The test pieces shall be kept in the oven at the temperature and for the time specified for the
material in the relevant standard for the type of cable.
As soon as the ageing period is completed, the test pieces shall be removed from the oven
and left at ambient room temperature, avoiding direct sunlight, for at least 16 h.
4.2.3.3 Ageing procedure for test pieces prepared from conductors above 16 mm
The following procedure shall be used when the conductor and the separator, if any, cannot
be removed without damaging the insulation after ageing.
The test pieces prepared as described in B.2.3.1 shall be placed substantially in the middle of
the oven so that each test piece is at least 20 mm from any other test pieces. They shall be
supported at both ends and the insulation shall not contact any object other than the binding
wire. The test pieces shall not occupy more than 2 % of the volume of the oven, and they
shall be kept in the oven at the temperature and for the time specified in the relevant standard
for the type of cable.
As soon as the ageing period is completed, the test pieces shall be removed from the oven,
left at ambient room temperature avoiding direct sunlight, for at least 16 h, dumb-bell are
prepared as described in B.2.3.2.
4.2.3.4 Ageing procedure for pieces of complete cable
The three test pieces of cable as described in Clause C.1 shall be suspended vertically and
substantially in the middle of the oven at least 20 mm away from any other piece and shall not
occupy more than 2 % of the volume of the oven.
The test pieces of cable shall be kept in the oven at the temperature and for the time
specified in the relevant standard for the type of cable.
As soon as the specified heating period is completed, the test pieces of cable shall be
removed from the oven and left at ambient room temperature, avoiding direct sunlight, for at
least 16 h.
4.2.4 Measurements
Determination of the mechanical properties on aged dumb-bell and/or tubular test pieces
obtained directly after ageing or prepared after ageing, according to the case (see B.2.3 or
Clause C.2) shall then be carried out in accordance of IEC 60811-501.
4.2.5 Expression of results
Calculate the tensile strength and the elongation at break, according to the definitions given
in IEC 60811-501.
 IEC 2017
If required by the standard for the material in the relevant standard for the type of cable, the
values found for the aged test pieces shall be calculated, in terms of variation compared to
the untreated test pieces according to the following formulae:
T − T
E U
V = × 100 (1)
T
T
U
E − E
E U
V = × 100 (2)
E
E
U
where
V variation of the tensile strength in per cent;
T
T tensile strength of aged test piece;
E
T tensile strength of untreated test piece;
U
V variation of the elongation at break in per cent;
E
E elongation at break of aged test piece in per cent;
E
E elongation at break of untreated test piece in per cent.
U
NOTE The untreated specimen is kept at room temperature.
4.2.6 Requirements
The value and the variation between the median value obtained of the test pieces aged and
the median value of the values obtained for the untreated test pieces (see IEC 60811-501)
expressed as a percentage of the latter shall not exceed the percentage specified in the
standard for the material in the relevant standard for the type of cable.
4.2.7 Test report
The test report shall be in accordance with that given in IEC 60811-100.
4.3 Bending test on test pieces of core
4.3.1 Apparatus
Ageing is carried out in an oven as described in 4.2.1.
The bending test apparatus is described in IEC 60811-504.
4.3.2 Sample and test pieces preparation
Two samples of suitable length shall be taken from each core to be tested preferably from
positions close to that from which the samples for the tensile tests without ageing are taken
(see IEC 60811-504).
4.3.3 Procedure
Test pieces are aged according to the procedure described in 4.2.3.3.
As soon as the ageing period is completed, the test pieces shall be removed from the oven
and left at room temperature, avoiding direct sunlight, for at least 16 h.
Each test piece shall then be bent at ambient room temperature around a mandrel so as to
form a close helix.
– 10 – IEC 60811-401:2012+AMD1:2017 CSV
 IEC 2017
The bending procedure shall be carried out uniformly at a rate of one turn in about 5 s.
The bending tests may be carried out with the apparatus described in IEC 60811-504.
The diameter of the mandrel shall be f times the diameter of the core. The values of f and also
the number of turns are specified as follows.
Table 1 – Number of turns for bending test
Cross-sectional area
Factor
of conductor Number of turns
f
mm
Up to and including 2,5 7
1 ±0,1
4 and 6 6
2 ±0,1
10 and 16 5
4 ±0,1
4.3.4 Requirement
At the end of the bending procedure the test pieces shall be examined while still on the
mandrel. The insulation of both test pieces shall not show any crack when examined with
normal or corrected vision without magnification. Any cracks in the first or the last turn on the
mandrel shall be disregarded.
4.3.5 Test report
The test report shall be in accordance with that given in IEC 60811-100.

 IEC 2017
Annex A
(normative)
Methods of measuring air flow in ovens

A.1 Method 1 – Indirect or power consumption method
A.1.1 In this method, the additional power required to maintain the oven at a given
temperature with its ports open, over that required to maintain the oven at the same
temperature with its ports closed, is used as a measure of the quantity of air passing through
the oven when the ports are open. The average power (P1 watts) required to maintain the
oven temperature at the specified ageing temperature when the ports are open is determined
over a period of 30 min or longer. The ventilation ports (and, if necessary, the thermometer
aperture) are then closed and the average power (P2 watts) to maintain the same temperature
over a similar period is determined. It is essential that the difference between the oven
temperature and the room temperature should be the same for the two tests to within 0,2 °C.
The room temperature should be measured at a point about 2 m from the oven, approximately
level with its base, and at least 0,6 m from any solid objects.
A.1.2 The amount of air passing through the oven, when the ports are open, is given by the
formulae:
P1− P2
m= (A.1)
C (t − t )
p 2 1
3 600 m
V= (A.2)
d
where
–1 –1
C is the specific heat of air constant pressure (J×g ×K );
p
t  is the room temperature, in degrees Celsius;
t  is the oven temperature, in degrees Celsius;
P1 – P2 is the difference in power consumption, as defined in A.1.1;
m  is the mass of air, in grams per second;
V  is the volume of air, in litres per hour;
d  is the density of air in the laboratory at the time of test, in grams per litre.
NOTE The density of air at 101,3 kPa (760 mm Hg) and 20 °C is 1,205 g/l.
3 600(P1− P2) 3 590(P1− P2)
Hence: or
V= V=
1,003 d (t − t ) d (t − t)
2 1 2 1
This formula assumes that, when the ports are closed, no air passes through the oven. Therefore, there should
be no leakages; the air-tight door joint should be sealed with adhesive tape and all apertures, including the inlet
port, should be effectively closed.
A.1.3 If the power consumption is measured with a wattmeter, the total length of time, in
seconds, for which the oven heaters are “on” shall be measured with a stop-watch and the
reading of the wattmeter shall be taken once during each "on" period.
The average of the wattage readings multiplied by the total time registered by the stop-watch
and divided by the duration of the test, in seconds, is taken as the power, in watts, required to
maintain a constant temperature.

– 12 – IEC 60811-401:2012+AMD1:2017 CSV
 IEC 2017
A.1.4 If a watt-hour or kilowatt-hour meter is used, the reading of the total energy
consumption registered by the meter shall be divided by the duration of the test, measured as
a fraction of an hour. If a household kilowatt-hour meter is used, the dial units are too large to
enable a sufficient accuracy to be obtained over a reasonably short test, and the rotating disc
with which these meters are provided shall be used therefore as the power consumption
indicator. The meter shall be put into operation until the index mark on the disc is opposite the
centre of the window; it shall then be disconnected until the start of the test.
To reduce the possible error, the period of test shall be long enough to permit 100 revolutions
of the disc and the test shall preferably be ended when the mark on the disc is visible. If,
however, the mark is out of sight at the end of the test, an estimated fraction of a revolution
shall be added. The test shall be started and stopped at corresponding points on the "on-off"
heating cycle (e.g., at the moment when the heaters are switched on by the thermostat).
A.2 Method 2 – Direct and continuous method
A.2.1 Description of the equipment
Starting from the high-pressure air source, i.e. from a pipe system or air cylinders:
A.2.1.1 Air pressure regulator
A device to reduce the air pressure from the many atmospheres of the supply mains to the
quite low-pressure values needed for supplying the oven. It is equipped with an adjustable
valve which permits a constant pressure downstream.
A.2.1.2 Flowmeter
An instrument with which the rate of air flow can be measured. It is illustrated by Figure A.1,
and operates on a manometric principle, with:
a) A calibrated capillary tube, with an internal calibrated diameter of about 2 mm and a
calibrated length of about 70 mm. Figure A.2 shows a typical calibration diagram which
permits the control of air flow up to 500 l/h or 600 l/h.
b) A manometric tube with a double graduation of pressure difference ranging between
0 mm and ±300 mm of water. Distilled water is the manometric liquid.
A.2.1.3 Air oven
An air oven to be operated when carefully sealed, including sealing round the inlet tube,
which should preferably enter the oven through the bottom. The outflow hole, which should be
at the top of the oven, is the only port to be open.
NOTE The following two features facilitate the reliability of the method and the equipment:
– the flowmeter described above can be considered as fully reliable, easy to manufacture and to calibrate, as
well as suitable for the range of air rates involved here;
– as shown by tests the adoption of a slightly “forced” ventilation does not alter, in practice, the uniformity of the
temperature at the various points in the ovens.

 IEC 2017
IEC  256/12
Figure A.1 – Flowmeter for air-flow control in air ovens for method 2

– 14 – IEC 60811-401:2012+AMD1:2017 CSV
 IEC 2017
IEC  257/12
Key
P pressure differences, millimetres of water
A air flow in litres per hour
NOTE Capillary tube, diameter: d = 2 mm; length: l = 70 mm.
Figure A.2 – Calibration diagram of the capillary tube of the flowmeter
for air-flow control in air ovens for method 2

 IEC 2017
Annex B
(normative)
Test pieces preparation in presence of copper
or metal coated copper conductor

B.1 Test pieces preparation of cores with the original conductor
When the conductor and the separator, if any, can be removed without damaging the
insulation after ageing, the procedure shall be as follows: samples of core, cut into pieces
which are sufficiently long, shall be taken, preferably from positions close to that from which
the samples for the tensile tests without ageing are taken in accordance with IEC 60811-501.
They shall then be aged as described in 4.2.3.2, after which the conductor shall be removed
and the cross-sectional area of the test pieces shall be determined according to
IEC 60811-501.
B.2 Test pieces preparation in case of adhesion of conductor insulation or
separator after ageing
B.2.1 General
When it is not possible to remove the conductor or the separator, if any, after the ageing
procedure without damaging the insulation, the appropriate preparation and test method shall
be applied as given in Table B.1.
Table B.1 – Summary of ageing tests for insulated conductors in case of
difficulties in preparing test pieces due to conductor insulation or
separator adhesion during ageing
Class of copper conductor
Test method
and conductor form acc. to IEC 60228
Class 1: plain copper See B.2.2.1 or, if this method also gives rise to adhesion
problems, see 4.3.
Ageing followed by the bending test is considered the acceptance
procedure in case of dispute
Class 1: metal coated or with a separator See 4.3
around the conductor
Class 2: circular conductors up to and See 4.3
including 16 mm and having plain or metal
coated wires and with or without separator
as appropriate
Class 2: conductors above 16 mm , circular See 4.2.3.3
or shaped, and having plain or metal-coated
wires
Classes 5 and 6: conductors up to and See B.2.2.2 or if this method also gives rise to adhesion problems
including 16 mm having plain or metal- see 4.3.
coated wires and with or without separator
Ageing followed by the bending test is considered the acceptance
as appropriate
procedure in case of dispute
Classes 5 and 6: conductors above 16mm See 4.2.3.3
having plain or metal-coated wires
NOTE In the case of the bending test (4.3), ageing conditions may be different from those requiring the
determination of tensile properties (Clause B.1 and B.2.2); see the relevant cable standard.

– 16 – IEC 60811-401:2012+AMD1:2017 CSV
 IEC 2017
B.2.2 Tubular test pieces preparation with a reduced conductor
B.2.2.1 Solid plain conductor with reduced diameter
After preparation of five tubular test pieces in accordance with IEC 60811-501 a piece of solid
plain conductor, having a diameter reduced by up to 10 % shall be reinserted. This shall be
achieved by stretching the original conductor or by using a conductor having the required
smaller diameter.
These tubular test pieces shall then be aged as described in 4.2.3.2 after which the reduced
conductor shall be removed and the cross-sectional area of the tubular test pieces shall be
determined according to IEC 60811-501.
B.2.2.2 Class 5 and class 6 conductor with a reduced number of wires
The preparation of five tubular test pieces shall be carried out in accordance with IEC 60811-
501. For this purpose, either approximately 30 % of the wires forming the conductor may be
removed from the insulation or approximately 70 % of the wires may be reinserted into the
tubular test piece.
These tubular test pieces shall then be aged as described in 4.2.3.2 after which the reduced
conductor shall be removed and the cross-sectional area of the tubular test pieces shall be
determined according to IEC 60811-501.
B.2.3 Test pieces preparation for conductors above 16 mm
B.2.3.1 Sampling and preparation of test pieces for ageing
Three test pieces each about 200 mm long shall be taken from each core to be tested,
preferably from positions close to that from which the samples for the tensile tests without
ageing are taken (see IEC 60811-501).
In the case of sector-shaped cores, a strip of not less than 10 mm width shall be cut out of the
insulation at the sector back along the conductor axis and separated from the conductor.
Subsequently, this strip shall be applied again in the same place and fastened with suitable
wire in the middle of the test piece and at about 20 mm from each end in such a way that the
strip is again well in contact with the conductor; see Figure B.1 below.

 IEC 2017
IEC  258/12
Key
1 binding wire (aluminium or zinc-coated steel)
Figure B.1 – Specially prepared test pieces
For cores with circular conductors, a similar procedure shall be applied, where, for smaller
), up to half the insulation can be separated.
sizes (for example, 25 mm
B.2.3.2 Dumb-bell tests pieces preparation after ageing
Aged test pieces are dismantled and dumb-bell test pieces, two from each test pieces, shall
then be prepared in accordance with IEC 60811-501, the cross-sectional area being
determined in accordance with IEC 60811-501, as shown in the Figure B.2 below.

IEC  259/12
Figure B.2 – Dumb-bell test pieces preparation after ageing

– 18 – IEC 60811-401:2012+AMD1:2017 CSV
 IEC 2017
Annex C
(normative)
Sample and test pieces preparation for ageing of complete cable

C.1 Sampling and preparation of test pieces for ageing
Three test pieces of complete cable about 200 mm long shall be taken, preferably from
positions close to that from which the samples for the tensile tests without ageing (see
IEC 60811-501) are taken.
C.2 Dumb-bell or tubular tests pieces preparation after ageing
The aged three test pieces of cable shall be dismantled at least 16 h but not more than 24 h
after the end of the ageing period. Two dumb-bell or tubular test pieces shall be prepared
from the insulation of each core (up to a maximum of three cores) and from the sheath of
each piece of cable, as specified in IEC 60811-501 so that there are six test pieces from each
core and from the sheath.
If the test pieces need to be cut or ground to reduce their thickness to not more than 2 mm,
this operation shall be effected, so far as possible, on the side which was not facing a
material of different type in the complete cable. If ridges need to be cut or ground on the side
which was facing the different type of material, the material removed on that side shall be the
minimum compatible with adequate smoothing.

 IEC 2017
Bibliography
IEC 60811-1-2:1985, Common test methods for insulating and sheathing materials of electric
cables – Part 1: Methods for general application – Section Two – Thermal ageing methods
(withdrawn)
______________
– 20 – IEC 60811-401:2012+AMD1:2017 CSV
 IEC 2017
SOMMAIRE
AVANT-PROPOS . 21
INTRODUCTION . 23
1 Domaine d’application . 24
2 Références normatives . 24
3 Termes et définitions . 24
4 Méthode d’essai . 24
4.1 Généralités. 24
4.2 Influence du traitement de vieillissement sur les caractéristiques mécaniques . 25
4.2.1 Appareillage . 25
4.2.2 Echantillons et préparation des éprouvettes . 25
4.2.3 Méthode de vieillissement . 25
4.2.4 Mesures . 27
4.2.5 Expression du résultat . 27
4.2.6 Exigences . 27
4.2.7 Rapport d’essai . 27
4.3 Essai d’enroulement sur des éprouvettes de conducteur . 27
4.3.1 Appareillage . 27
4.3.2 Echantillons et préparation des éprouvettes .
...