IEC 62677-2:2017

IEC 62677-2 ®
Edition 1.0 2017-10
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Heat shrinkable low and medium voltage moulded shapes –
Part 2: Methods of test
Profilés thermorétractables basse et moyenne tensions –
Partie 2: Méthodes d’essai
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IEC 62677-2 ®
Edition 1.0 2017-10
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Heat shrinkable low and medium voltage moulded shapes –

Part 2: Methods of test
Profilés thermorétractables basse et moyenne tensions –

Partie 2: Méthodes d’essai
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.035.20; 29.035.01 ISBN 978-2-8322-4869-0

– 2 – IEC 62677-2:2017 © IEC 2017
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 8
2 Normative references . 8
3 Terms and definitions . 9
4 Test conditions . 9
5 Standard test specimens . 9
6 Dimensions. 9
6.1 Number of test specimens . 9
6.2 Procedure . 9
6.3 Result . 10
7 Heat shock . 10
7.1 Number of test specimens . 10
7.2 Form of test specimens . 10
7.3 Procedure . 10
7.4 Report. 10
7.5 Result . 10
8 Bending at low temperature . 10
8.1 Number and form of test specimens . 10
8.2 Procedure . 10
8.3 Result . 10
9 Dimensional stability on storage . 10
9.1 Number of test specimens . 10
9.2 Procedure . 11
9.3 Result . 11
10 Tensile strength and elongation at break . 11
10.1 Number and form of test specimens . 11
10.2 Conditioning . 12
10.3 Test temperature . 12
10.4 Procedure . 12
10.5 Calculations . 12
10.6 Report. 12
10.7 Result . 12
11 Secant modulus at 2 % elongation . 13
11.1 Number and form of test specimens . 13
11.2 Procedure . 13
11.3 Calculation . 13
11.4 Report. 13
11.5 Result . 13
12 Electric strength . 13
12.1 Number and form of test specimens . 13
12.2 Conditioning . 13
12.3 Electrodes . 13
12.4 Procedure . 14
12.5 Report. 14

12.6 Result . 14
13 Volume resistivity . 14
13.1 Number and form of test specimens . 14
13.2 Electrodes . 14
13.3 Procedure . 14
13.4 Report. 14
13.5 Result . 14
14 Permittivity and dissipation factor . 14
14.1 Number and form of test specimens . 14
14.2 Electrodes . 14
14.3 Procedure . 14
14.4 Calculation . 14
14.5 Result . 15
15 Resistance to tracking . 15
15.1 Procedure . 15
15.2 Report. 15
15.3 Result . 15
16 Flammability . 15
16.1 Method A . 15
16.1.1 Number and form of test specimens . 15
16.1.2 Procedure . 15
16.1.3 Result . 15
16.2 Method B . 15
16.2.1 Number and form of test specimens . 15
16.2.2 Apparatus . 15
16.2.3 Procedure . 15
16.2.4 Result . 16
17 Carbon black content . 16
17.1 Number and form of test specimens . 16
17.2 Procedure . 16
17.3 Report. 16
17.4 Result . 17
18 Resistance to selected fluids . 17
18.1 Principle . 17
18.2 Choice of fluid . 17
18.3 Methods of assessment . 17
18.4 Number and form of test specimens . 17
18.5 Procedure . 17
18.6 Result . 18
19 Long term heat ageing (3 000 h) . 18
19.1 Number and form of test specimens . 18
19.2 Procedure . 18
19.3 Report. 18
19.4 Result . 18
20 Heat ageing . 18
20.1 Number and form of test specimens . 18
20.2 Procedure . 18
21 Water absorption . 18

– 4 – IEC 62677-2:2017 © IEC 2017
21.1 Procedure . 18
21.2 Report. 18
21.3 Result . 18
22 Resistance to mould growth . 19
22.1 Test in accordance with ISO 846 . 19
22.2 Report. 19
22.3 Result . 19
23 Peel adhesion . 19
23.1 Principle . 19
23.2 Apparatus . 19
23.3 Form and number of test specimens . 19
23.4 Procedure . 19
23.5 Calculation . 20
23.6 Report. 20
23.7 Result . 20
24 Copper corrosion (presence of corrosive volatiles) . 20
24.1 Principle . 20
24.2 Apparatus . 20
24.3 Number and form of test specimens . 21
24.4 Procedure . 21
24.5 Report. 21
24.6 Result . 21
25 Halogen content . 21
25.1 Method for the determination of low levels of chlorine and/or bromine and/or
iodine . 21
25.1.1 Principle . 21
25.1.2 Apparatus . 22
25.1.3 Procedure . 22
25.2 Determination of low levels of fluorine . 22
25.2.1 Principle . 22
25.2.2 Apparatus . 22
25.2.3 Reagents . 23
25.2.4 Procedure . 23
25.3 Result . 23
26 Adhesive temperature resistance . 23
26.1 Number and form of test specimens . 23
26.2 Procedure . 23
26.3 Report. 23
26.4 Result . 24
27 Resistance to weathering . 24
27.1 Number and form of test specimens . 24
27.2 Procedure . 24
27.3 Report. 24
Bibliography . 25

Figure 1 – Dumb-bell specimen for tensile strength test . 11
Figure 2 – Test arrangement for flammability to Clause 16 method B . 16
Figure 3 – Test arrangement for heat shrink moulded shape on metal tube or cable . 20

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
HEAT SHRINKABLE LOW AND MEDIUM
VOLTAGE MOULDED SHAPES –
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
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
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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
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3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
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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
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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 62677-2 has been prepared by committee TC15: Solid electrical
insulating materials.
The text of this standard is based on the following documents:
FDIS Report on voting
15/807/FDIS 15/811/RVD
Full information on the voting for the approval of this International Standard can be found in
the report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts in the IEC 62677 series, published under the general title Heat shrinkable
low and medium voltage moulded shapes, can be found on the IEC website.

– 6 – IEC 62677-2:2017 © IEC 2017
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
INTRODUCTION
This part of IEC 62677 is one of a series which deals with heat shrinkable low and medium
voltage moulded shapes. The series consists of three parts:
Part 1: General requirements (IEC 62677-1 )
Part 2: Methods of test (IEC 62677-2)
2 3 4
Part 3: Material requirements (IEC 62677-3-101 , IEC 62677-3-102 and IEC 62677-3-103 )

____________
Under preparation. Stage at the time of publication: IEC RFDIS IEC 62677-1:2017.
Under preparation. Stage at the time of publication: IEC AFDIS IEC 62677-3-101:2017.
Under preparation. Stage at the time of publication: IEC AFDIS IEC 62677-3-102:2017.
Under preparation. Stage at the time of publication: IEC ACDV IEC 62677-3-103:2017.

– 8 – IEC 62677-2:2017 © IEC 2017
HEAT SHRINKABLE LOW AND MEDIUM
VOLTAGE MOULDED SHAPES –
Part 2: Methods of test
1 Scope
This part of IEC 62677 gives methods of test for heat shrinkable low and medium voltage
moulded shapes in a range of configurations and materials suitable for insulation,
environmental sealing, mechanical protection and strain relief for connector/cable
terminations and multi-way transitions.
The tests specified are designed to control the quality of the moulded shapes but it is
recognized that they are designed to be used in low and medium voltage cable accessories
and as such electrical performance will be proven as part of the assembly. Examples of this
are described in EN 50393, HD 629.1 and IEC 60502-4.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their
content constitutes requirements 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 60212:2010, Standard conditions for use prior to and during the testing of solid electrical
insulating materials
IEC 60216-4-1:2006, Electrical insulating materials – Thermal endurance properties – Part 4-
1: Ageing ovens – Single-chamber ovens
IEC 60216-4-2:2000, Electrical insulating materials – Thermal endurance properties – Part 4-
2: Ageing ovens – Precision ovens for use up to 300 °C
IEC 60243-1:2013, Electric strength of insulating materials – Test methods – Part 1: Tests at
power frequencies
IEC 60250:1969, Recommended methods for the determination of the permittivity and
dielectric dissipation factor of electrical insulating materials at power, audio and radio
frequencies including metre wavelengths
IEC 60587:2007, Electrical insulating materials used under severe ambient conditions – Test
methods for evaluating resistance to tracking and erosion
IEC 62631-3-1:2016, Dielectric and resistive properties of solid insulating materials – Part
3-1: Determination of resistive properties (DC methods) – Volume resistance and volume
resistivity  General method
IEC 60695-11-2:2013, Fire hazard testing – Part 11-2: Test flames – 1 kW pre-mixed flame –
Apparatus, confirmatory test arrangement and guidance
IEC 60695-11-10:2013, Fire hazard testing – Part 11-10: Test flames – 50 W horizontal and
vertical flame test methods
IEC 62677-3 (all parts), Heat shrinkable low and medium voltage moulded shapes
ISO 62:2008, Plastics – Determination of water absorption
ISO 846:1997, Plastics – Evaluation of the action of microorganisms

ISO 4892-3:2016, Plastics – Methods of exposure to laboratory light sources – Part 3:
Fluorescent UV lamps
ISO 11357-3:2011, Plastics – Differential scanning calorimetry (DSC) – Part 3: Determination
of temperature and enthalpy of melting and crystallization
ISO 11358-1:2014, Plastics – Thermogravimetry (TG) of polymers - Part1: General principles
ISO 11358-2:2014, Plastics – Thermogravimetry (TG) of polymers - Part 2: Determination of
activation energy
3 Terms and definitions
No terms and definitions are listed in this document.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
4 Test conditions
4.1 Unless otherwise specified, all tests shall be made under standard ambient conditions
according to IEC 60212, that is at a temperature between 15 °C and 35 °C and at ambient
relative humidity.
In cases of dispute, the tests shall be carried out at a temperature of 23 °C ± 2 K and at
(50 ± 5) % relative humidity.
4.2 When heating at elevated temperature is specified for a test procedure, the specimen
shall be maintained for the prescribed period in a uniformly heated oven complying with either
IEC 60216-4-1 or IEC 60216-4-2.
4.3 Where a test at low temperature is specified, the specification sheets of
IEC 62677-3 (all parts) may require it to be carried out at t °C or lower, where t is the
requested temperature. In such cases, the operator may carry out the test at the specified
temperature or any lower temperature which is convenient. If, however, at a temperature
below that specified, the specimen fails to meet the requirements, the test shall be repeated
at the specified temperature, subject to a tolerance of ±3 K as specified in IEC 60212. If the
specimen then passes, it shall be considered to have met the requirements.
5 Standard test specimens
Moulded shape material specimens shall be prepared from (2 ± 0,15) mm thick sheets, unless
otherwise specified, and shall be prepared from the same heat shrinkable material and
conditions (including cross-linking) that is to be used to manufacture the heat shrinkable
moulded shapes. The dimensions of the sheet shall be sufficient to enable any of the relevant
tests to be performed.
NOTE A suitable size has been found to be 150 mm × 150 mm.
6 Dimensions
6.1 Number of test specimens
Three specimens of each size and style shall be tested.
6.2 Procedure
Measure the moulded shapes in the as supplied condition and after unrestricted shrinkage as
specified in IEC 62677-3 (all parts). Carry out unrestricted shrinkage by conditioning in an
oven for the time and temperature specified in IEC 62677-3 (all parts). Remove the shapes
from the oven and allow to cool naturally to the ambient temperature specified in Clause 4.

– 10 – IEC 62677-2:2017 © IEC 2017
The method of measurement can be mechanical or optical. Wall thickness shall be measured
to an accuracy of ±0,05 mm and internal diameter to an accuracy of ±0,1 mm. In the case of
dispute an optical method shall be used.
6.3 Result
Report all measured values as the result.
7 Heat shock
7.1 Number of test specimens
Three specimens shall be tested.
7.2 Form of test specimens
Cut three specimens in accordance with Clause 10, from a test sheet in accordance with
Clause 5.
7.3 Procedure
The specimens shall be suspended vertically in an oven for 4 h ± 10 min at the temperature
specified in IEC 62677-3 (all parts).
The specimens shall be removed and allowed to cool to room temperature. They shall then be
visually examined for any signs of dripping, cracking or flowing. In addition, when so specified
in IEC 62677-3 (all parts) the specimens shall be tested for tensile strength and elongation at
break.
7.4 Report
Report all results from the visual examination. Report all values from the tensile strength and
elongation test.
7.5 Result
The result for each property is the central value unless otherwise specified in the specification
sheets of IEC 62677-3 (all parts).
8 Bending at low temperature
8.1 Number and form of test specimens
Cut three specimens from a test sheet in accordance with Clause 5 approximately
150 mm × 6 mm.
8.2 Procedure
The specimens shall be suspended for 4 h ± 10 min in a chamber maintained at the
temperature specified in IEC 62677-3 (all parts). While still at that temperature, they shall be
wound without jerking for one complete turn in a close helix round a mandrel also at the same
temperature and having a diameter specified in IEC 62677-3 (all parts). The time to achieve
one complete turn shall not be greater than 5 s. The specimens shall then be allowed to
return to room temperature.
The specimens shall then be visually examined without magnification while still on the
mandrel for signs of cracking.
8.3 Result
Report whether there is any cracking.
9 Dimensional stability on storage
9.1 Number of test specimens
Three shapes shall be tested.
9.2 Procedure
The internal diameter of each outlet shall be measured in the expanded state as delivered.
The shapes shall then be stored in a ventilated oven as detailed in 4.2 for (336 ± 2) h at a
temperature of 40 °C ± 3 K unless otherwise specified in the relevant sheet of
IEC 62677-3 (all parts). They shall then be removed from the oven, allowed to cool to ambient
temperature and the same dimensions re-measured. The accuracy of measurement shall be
in accordance with Clause 6.
Following this measurement, the shapes shall be allowed to fully recover, using the time and
temperature specified in IEC 62677-3 (all parts) for the shapes being evaluated. The shapes
shall then be cooled to ambient temperature and the recovered dimensions measured.
9.3 Result
Report, as the result, all measured values for each of the three sets of measurements: the
expanded dimensions before and after storage at elevated temperature, and the fully
recovered dimensions after storage at elevated temperature.
10 Tensile strength and elongation at break
10.1 Number and form of test specimens
Cut five dumb-bell specimens from a test sheet in accordance with Clause 5 to the
dimensions and tolerances given in Figure 1. The specimens shall be stamped from the sheet
using a single stroke of a press and a knife edge punch of appropriate form and dimensions.
NOTE The profile given in Figure 1 is that of type 2 of ISO 37.
Dimensions in millimetres
A
C
G
F
E
Position of
reference lines
IEC
A = overall length, minimum 75 mm
B = width at ends (12,5 ± 1,0) mm
C = length of narrow parallel portions (25 ± 1) mm
D = width of narrow parallel portion (4,0 ± 0,1) mm
E = small radius (8,0 ± 0,5) mm
F = large radius (12,5 ± 1,0) mm
G = distance between reference lines 20 mm maximum
In any one specimen, the thickness of the narrow portion shall nowhere deviate by more than 2% from the mean.
Figure 1 – Dumb-bell specimen for tensile strength test
B
D
– 12 – IEC 62677-2:2017 © IEC 2017
10.2 Conditioning
Unless otherwise specified in IEC 62677-3 (all parts), the test specimens shall be kept at an
ambient temperature of 23 °C ± 2 K for at least 1 h before testing, or for a longer time to
enable the specimens to reach a temperature of 23 °C ± 2 K.
10.3 Test temperature
The test shall be made at a temperature of 23 °C± 2 K.
10.4 Procedure
The width and thickness of the central parallel portion of the specimen shall be measured
between the gauge marks to the nearest 0,01 mm at a minimum of three points. The average
cross-sectional area is then determined.
The specimen shall be mounted in the tensile test machine in axial alignment with the
direction of pull. The jaws shall be separated at the uniform rate specified in
IEC 62677-3 (all parts) for a particular material. The range of the testing machine shall be
such that the maximum load is between 15 % and 85 % of the maximum scale reading.
The distance between the reference lines at break may conveniently be measured by means
of a rule, callipers or an extensometer.
The maximum load shall be measured to an accuracy of 2 %. The distance between the
reference lines at break shall be measured to within 2 mm.
If the test specimen breaks outside the reference lines the result shall be discarded and a
further test made using another specimen.
10.5 Calculations
The tensile strength S shall be calculated from the maximum load and the original area of
cross-section, and the result expressed in megapascals (MPa):
F
max.
S = (MPa)
A
where
F is the maximum load (N);
max.
A is the original cross-sectional area (mm ).
The elongation at break E shall be expressed as a percentage of the original distance
between the reference lines, i.e.:
L − L
E = × 100 (%)
L
where
L is the measured distance between the two reference lines on the stretched specimen
at break;
L is the original distance between the two reference lines.

10.6 Report
Report all calculated values.
10.7 Result
The result for each property is the central value unless otherwise specified in the specification
sheets of IEC 62677-3 (all parts).

11 Secant modulus at 2 % elongation
11.1 Number and form of test specimens
Perform three tests on strips cut from a test sheet in accordance with Clause 5. The width of
the strips shall be approximately 20 mm.
11.2 Procedure
The procedure is as follows.
a) The secant modulus shall be calculated from the determination of the tensile stress
necessary to produce in the specimen an extension of 2 % of the length between jaws or
between reference lines.
b) Depending on the method of measurement chosen, the length of the specimen between
the jaws or reference lines shall be not less than 100 mm.
c) The extension may be measured by means of an extensometer or by jaw separation; the
extension shall be measured to an accuracy of 2 %.
d) The strain rate shall be (0,1 ± 0,03) mm/min for each millimetre length between jaws (e.g.
12 mm/min for a 120 mm length between jaws).
e) An initial tensile force (F) may need to be applied to the specimen for the purpose of
straightening it. This force shall not exceed 3 % of the final value.
f) The force shall be increased until the extension between the jaws or reference lines
reaches 2 %. The force (F ) required to produce this extension shall be recorded.
11.3 Calculation
The 2 % secant modulus of the specimen (M) shall be calculated as follows:
F − F
M = (MPa)
0,02A
where
A is the initial average cross-sectional area of the specimen (mm ) (determined as specified
in 10.4);
F is the force required to produce a 2 % extension (N);
F is the force applied to produce the initial (straightening) stress (N).
11.4 Report
Report all measured values for the secant modulus at 2 % elongation.
11.5 Result
The result is the central value unless specified otherwise in the specification sheets of
IEC 62677-3 (all parts).
12 Electric strength
12.1 Number and form of test specimens
Three specimens shall be tested using standard test sheets in accordance with Clause 5.
12.2 Conditioning
In case of doubt or dispute, these tests shall be made on specimens which have been
conditioned by exposure for not less than 24 h to an ambient atmosphere of temperature
23 °C ± 2 K and (50 ± 5) % relative humidity.
12.3 Electrodes
The electrodes shall be in accordance with IEC 60243-1, that is, unequal diameter electrodes
for sheet materials.
– 14 – IEC 62677-2:2017 © IEC 2017
12.4 Procedure
The electrodes shall be placed in the centre of the test sheet as described in IEC 60243-1 and
the assembly placed in transformer oil.
The voltage used shall be in accordance with IEC 60243-1 and applied between the two
electrodes at a uniform rate from zero, such that bre
...