IEC 62641:2022

IEC 62641 ®
Edition 1.0 2022-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Conductors for overhead lines – Aluminium and aluminium alloy wires for
concentric lay stranded conductors

Conducteurs pour lignes aériennes – Fils d’aluminium et en alliage d’aluminium
pour conducteurs toronnés à couches concentriques

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IEC 62641 ®
Edition 1.0 2022-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Conductors for overhead lines – Aluminium and aluminium alloy wires for

concentric lay stranded conductors

Conducteurs pour lignes aériennes – Fils d’aluminium et en alliage d’aluminium

pour conducteurs toronnés à couches concentriques

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.060.01; 29.240.20 ISBN 978-2-8322-1080-6

– 2 – IEC 62641:2022 © IEC 2022
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 Material . 8
5 Joints . 8
6 Tests . 8
6.1 General . 8
6.2 Place of testing . 8
6.3 Sampling rate . 9
6.4 Test methods . 9
6.4.1 Appearance . 9
6.4.2 Wire diameter . 9
6.4.3 Tensile strength . 9
6.4.4 Elongation . 9
6.4.5 Wrapping . 10
6.4.6 Bending . 10
6.4.7 Electrical resistivity . 10
6.4.8 Thermal resistance . 10
6.5 Acceptance and rejection . 11
6.6 Certificate of compliance . 11
7 Length and tolerance on length. 11
Annex A (normative) Methods of securing formed wires . 14
Annex B (informative) Thermal-resistant property . 15
B.1 Thermal-resistant properties . 15
B.2 Explanation of the Arrhenius plot . 15
B.3 Continuous operation temperature . 16
B.4 Duration and heating temperature . 16
Bibliography . 17

Figure A.1 – Methods of securing formed wires . 14
Figure B.1 – Arrhenius plot (residual strength 90 %) . 15

a b
Table 1 – Designation and properties for calculation purposes . 11
Table 2 – Tolerance on wire diameter . 12
Table 3 – Minimum mechanical properties for Ax and ALx wires . 12
Table 4 – Minimum mechanical properties for ATx wires . 13
Table 5 – Temperature and duration of heating . 13
Table 6 – Parameters for bending test of aluminium alloy wires . 13

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
CONDUCTORS FOR OVERHEAD LINES –
ALUMINIUM AND ALUMINIUM ALLOY WIRES
FOR CONCENTRIC LAY STRANDED CONDUCTORS

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 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. 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 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
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
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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
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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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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.
IEC 62641 has been prepared by IEC technical committee 7: Overhead electrical conductors.
It is an International Standard.
This first edition cancels and replaces the second edition of IEC 60104 published in 1987, the
first edition of IEC 60121 published in 1960, the first edition of IEC 60889 published in 1987,
and the first edition of IEC 62004 published in 2007. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
editions of IEC 60104, IEC 60121, IEC 60889 and IEC 62004:
a) designations of aluminium alloys are modified;
b) aluminium alloys A4, AL4 and AL5 are added;
c) wire diameter ranges for indicating mechanical properties are modified and extended;
d) test methods are merged.
– 4 – IEC 62641:2022 © IEC 2022
The text of this International Standard is based on the following documents:
Draft Report on voting
7/713/FDIS 7/721/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/standardsdev/publications.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under 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
The purpose of this document is threefold.
First, it is to group together similar wire materials that share the same general characteristics
and therefore the same test procedures and requirements. These wires are existing aluminium
and aluminium alloy wires from IEC 60104, IEC 60121, IEC 60889 and IEC 62004 as well as
from EN 50183.
Secondly, this format allows an easier standard maintenance, as multiple wire materials are
covered by a single document instead of separate documents.
Thirdly, this document indicates the most used wire materials worldwide, based on the
cooperation agreement between IEC and CENELEC, an IEC questionnaire in 2017 (7/672/Q,
Annex A) and a CENELEC questionnaire (7X/SEC0056/CC). The standardized materials form
a good basis which can be extended by others used in regions and countries.

– 6 – IEC 62641:2022 © IEC 2022
CONDUCTORS FOR OVERHEAD LINES –
ALUMINIUM AND ALUMINIUM ALLOY WIRES
FOR CONCENTRIC LAY STRANDED CONDUCTORS

1 Scope
This document specifies the mechanical and electrical properties of round and formed wires for
equivalent diameters up to the values according to Table 3 for aluminium and aluminium alloys
and according to Table 4 for thermal resistant alloys. This document is applicable to aluminium
and aluminium alloy wires for the manufacture of concentric lay overhead electrical stranded
conductors with or without gap(s) for power transmission purposes.
The various materials and their designations are listed in Table 1. For calculation purposes, the
values listed in Table 1 are used.
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 60050 (all parts), International Electrotechnical Vocabulary (IEV) (available at
www.electropedia.org)
IEC 60468, Method of measurement of resistivity of metallic materials
IEC TR 61597, Overhead electrical conductors – Calculation methods for stranded bare
conductors
ISO 6892-1, Metallic materials – Tensile testing – Part 1: Method of test at room temperature
ISO 7801, Metallic materials – Wires – Reverse bend test
ISO 7802, Metallic materials – Wires – Wrapping test
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60050 (all parts) and
the following apply.
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

3.1
aluminium
metallic element forming the base of alumina, being white with a bluish tinge and remarkable
for its resistance to oxidation and for its lightness
Note 1 to entry: See Ax and ALx in Table 1, 3.13 and Clause 4.
3.2
annealed aluminium
heat treated aluminium (A0 and AL0 in Table 1) resulting in its softest and most ductile state
and maintaining its mechanical and electrical properties at temperatures up to 250 °C
3.3
equivalent diameter
diameter of a round wire, which would have the same cross section area as a given formed wire
3.4
formed wire
drawn or rolled metal wire having a constant non-circular cross-section
3.5
lot
group of production units of one type and size of wire, which was manufactured by the same
manufacturer during the same time period under similar conditions of production
Note 1 to entry: A lot can consist of part or all of a purchased quantity.
3.6
nominal
value of a measurable property to which tolerance is applied
Note 1 to entry: Nominal values are target values.
3.7
production unit
coil, reel, spool, or other package of wire that represents a single usable length
3.8
residual strength ratio
ratio of the measured tensile strength at room temperature of a wire previously submitted to
heating, to its measured tensile strength at room temperature prior to heating
Note 1 to entry: This ratio is applied only to thermal resistant aluminium alloys.
3.9
round wire
filament of drawn metal having a constant circular cross-section
3.10
sample
specimen or specimens removed from a production unit or units which are considered to have
properties representative of a lot
3.11
specimen
length of wire removed for test purposes

– 8 – IEC 62641:2022 © IEC 2022
3.12
thermal resistance
capacity of a modified aluminium alloy to have a residual strength ratio of not les than 0,90 after
heating
3.13
thermal resistant aluminium alloy
all types of aluminium alloys (ATx in Table 1) designed to operate at temperatures continuously
higher than that of conventional aluminium alloy wires or hard-drawn aluminium wires with a
maximum allowable continuous operation temperature indicated in Table 5
Note 1 to entry: According to CIGRE TB 643, conventional conductor systems (using aluminium alloy or hard-drawn
aluminium wires) are traditionally rated at 75 °C continuous operation.
4 Material
The aluminium content of annealed and hard-drawn aluminium wires (A0, A1, AL0, AL1 in
Table 1) shall not be less than 99,5 %, aluminium alloys (A2, A3, A4, AL2, AL3, AL4, AL5 in
Table 1) shall be heat-treated aluminium-magnesium-silicon alloys, and thermal-resistant
aluminium alloys (ATx in Table 1) shall be aluminium-zirconium alloys. The wires shall be of
the required composition to achieve the mechanical, electrical and thermal-resistant (if required)
properties specified hereinafter.
If required by the purchaser, the manufacturer shall provide a copy of the analysis certificate of
the raw material.
5 Joints
Joints may be made in wires prior to final drawing. A joint may also be made in the finished wire
provided:
– the weight of the production unit with a joint is at least 500 kg;
– there shall be no more than one joint in such production units made before final drawing;
– by lot, the amount of production units with joints is less than or equal to 10 % of the total
amount of production units;
– when requested by the purchaser, the manufacturer shall provide evidence that the joints
have a tensile strength of not less than 130 MPa for all wires except A0 joints which shall
have not less than 60 MPa.
The production units containing a joint made in the finished wire shall be clearly identified.
6 Tests
6.1 General
Tests shall be made by the manufacturer on the wires to demonstrate their conformity to this
document. All described tests are sample tests except the 400 h thermal resistance test which
is a type test. The following test descriptions refer to non-stranded wires. In the case of formed
wires, use the equivalent diameter instead of the diameter and secure the wire in the jaws
according to Annex A.
6.2 Place of testing
Unless otherwise agreed between the purchaser and the manufacturer at time of ordering, all
tests shall be carried out at the manufacturer’s premises.

6.3 Sampling rate
Specimens for tests specified in Clause 6 shall be taken by the manufacturer from samples of
at least 10 % of each lot.
Alternatively, if a quality assessment procedure is in place and implemented, the sampling rate
shall be subject to agreement between the manufacturer and purchaser.
6.4 Test methods
6.4.1 Appearance
The surface of the wire shall be visually examined to ensure that it is smooth and free from all
imperfections including, but not limited to, cracks, unevenness, striation and inclusion
(particularly copper particles) which can compromise the performance of the final product.
6.4.2 Wire diameter
6.4.2.1 General
The nominal diameter of wires shall be expressed in millimetres to two decimal places.
When tested in accordance with 6.4.2.2 or 6.4.2.3 the diameter shall not vary from its nominal
value by more than the appropriate value indicated in Table 2.
6.4.2.2 Diameter for round wires
The diameter of a round wire shall be the mean of two direct measurements at right angle taken
at the same cross-section. The measurement apparatus shall have an accuracy of at least
0,001 mm.
6.4.2.3 Diameter for formed wires
The equivalent diameter of a formed wire shall be obtained from weight measurements made
on a sample not less than 1 m in length, and its density as defined in Table 1.
6.4.3 Tensile strength
One specimen cut from each of the samples taken under 6.3 shall be subjected to a tensile test
in accordance with ISO 6892-1. The rate of separation of the jaws of the testing machine shall
be not less than 25 mm/min and not greater than 100 mm/min.
When tested in accordance with 6.4.3, the tensile strength shall not be less than the appropriate
value given in Table 3 or Table 4. Tensile strength for annealed aluminium wires shall not
exceed 95 MPa. For nominal diameters outside the range given in Table 3 or Table 4, the
requirements shall be agreed upon between the purchaser and the supplier.
6.4.4 Elongation
One specimen cut from each of the samples taken under 6.3 shall be subjected to a tensile test
in accordance with ISO 6892-1. The rate of separation of the jaws of the testing machine shall
be not less than 25 mm/min and not greater than 100 mm/min. The elongation after fracture of
the wire shall be measured over a length of 250 mm between gauge marks on the wire itself,
the fracture being between the marks. Upon agreement between purchaser and manufacturer,
the elongation at break may be measured.

– 10 – IEC 62641:2022 © IEC 2022
When tested in accordance with 6.4.4, the elongation, expressed as a percentage of the original
gauge length, shall not be less than the appropriate value given in Table 3 or Table 4. For
nominal diameters outside the range given in Table 3 or Table 4, the requirements shall be
agreed upon between the purchaser and the supplier. If the fracture occurs outside the gauge
marks, or within 25 mm of either mark, and the required elongation is not obtained, another test
shall be made.
6.4.5 Wrapping
No wrapping test is required for annealed aluminium wires.
For hard drawn aluminium, aluminium alloy and thermal resistant aluminium alloy wires, one
specimen cut from each of the samples taken under 6.3 shall be subjected to a wrapping test
in accordance with ISO 7802. The diameter of the mandrel shall be equivalent to the equivalent
diameter of formed wire. Eight turns shall be wrapped around a mandrel of diameter equal to
the wire diameter at a speed not exceeding 60 rev/min. For hard drawn aluminium wires only,
six turns shall then be unwrapped and again closely wrapped.
When tested in accordance with 6.4.5, the wire shall not completely break.
6.4.6 Bending
No bending test is required for annealed aluminium wires.
For hard drawn aluminium, aluminium alloy and thermal resistant aluminium alloy wires, if
agreed between the purchaser and manufacturer at time of ordering, one specimen cut from
each of the samples taken under 6.3 shall be subjected to a bending test in accordance with
ISO 7801. For aluminium alloy wires, the radius of cylindrical support and the number of bending
cycles are given in Table 6.
When tested in accordance with 6.4.6, the sample shall show no cracks when examined with
the naked eye or normal corrective glasses.
6.4.7 Electrical resistivity
The electrical resistivity of a specimen cut from each of the samples taken under 6.3 shall be
determined by the method specified in IEC 60468.
When tested in accordance with 6.4.7, the resistivity at 20 °C shall not be greater than the value
indicated in Table 1.
6.4.8 Thermal resistance
6.4.8.1 General
This test is applicable to all thermal-resistant alloy wire types only. The sampling rate of the 1 h
test shall be in accordance with 6.3. The supplier shall submit reports of the 400 h test, made
in accordance with 6.4.8.2 to demonstrate compliance with the requirements of 6.4.8.3.
Information about thermal resistant properties is provided in Annex B.
6.4.8.2 Test method
Two specimens shall be secured from a continuous wire. One of the samples shall be kept in a
suitable heater for the designated duration and temperature as given in Table 5 and
subsequently tested at room temperature in accordance with 6.4.3. The other sample shall be
tested in accordance with 6.4.3 without prior heating.

6.4.8.3 Requirements
When tested in accordance with 6.4.8.2, the residual strength ratio shall not be less than 0,90.
6.5 Acceptance and rejection
Failure of a test specimen to comply with any one of the requirements of this document shall
constitute grounds for rejection of the lot represented by the specimen.
If any lot is so rejected, the manufacturer shall have the right to test all individual production
units in the lot once and submit those which meet requirements of acceptance.
6.6 Certificate of compliance
The manufacturer shall, if requested, provide the purchaser with a certificate giving the results
of all the tests carried out on the samples.
7 Length and tolerance on length
The nominal length of each production unit and the tolerance on length shall be subject to
agreement between the purchaser and the manufacturer.
a b
Table 1 – Designation and properties for calculation purposes
c
Maximum resistivity Mininum Constant-mass temperature
Designation
d
at 20 °C coefficient of resistance at
conductivity
IEC CENELEC
20 °C
-3
nΩ·m % IACS
10 /°C
A0 AL0 27,899 61,8 4,07
A1 AL1 28,264 61,0 4,03
A2 AL3 32,530 53,0 3,60
A3 AL2 32,840 52,5 3,60
A4 29,984 57,5 3,80
e f e f
AL4 3,60
32,900 32,600 52,4 52,9
e f e f
AL5 3,60
32,200 31,200 53,5 55,3
AT1 28,735 60,0 4,00
AT2 31,347 55,0 3,60
AT3 28,735 60,0 4,00
AT4 29,726 58,0 3,80
a
Table 1 reflects the most common used materials in the countries worldwide resulting from a market survey in
2017. Table 1 shall also be used as guideline for similar materials with similar or better properties, for example
higher conductivities for AL0 and AL1 which can be agreed between the purchaser and the supplier. Other or
new materials can be added in national or regional standards. Such materials may be proposed in the next
revision stage by NCs giving adequate justification and references.
b 3
For calculation purposes, a density of 2 703 kg/m and a coefficient of linear expansion of 0,000 023 1/K and
an E-modulus according to IEC TR 61597 shall be used for all listed materials.
c
Depending on history, regions and standardization committees, different designations for one and the same
material properties exist with the unavoidable consequence of inconsistent designations and numbering
sequence.
d
Values are for information only due to conversion according to IEC 60028 (resistance for standard annealed
copper: 17,241 nΩ·m) with potential rounding effects.
e
Of individual wires.
f
Mean of a lot
– 12 – IEC 62641:2022 © IEC 2022
Table 2 – Tolerance on wire diameter
Nominal wire diameter Tolerance
mm mm
Over Up to and including
-- 3,00 ±0,03
3,00 --- ±1 % of diameter
Table 3 – Minimum mechanical properties for Ax and ALx wires
a
Nominal wire diameter Minimum tensile Minimum
Designation
strength elongation after
--- mm
break
IEC CENELEC Over Up to and
including
MPa %
A0 AL0 -- 5,50 60 20
A1 AL1 -- 1,25 200
1,25 1,50 195
1,50 1,75 190
1,75 2,00 185
2,00 2,25 180 (No requirements)
2,25 2,50 175
2,50 3,00 170
3,00 3,50 165
3,50 5,00 160
A2 AL3 1,50 5,00 295 3,5
A3 AL2 1,50 3,50 325 3,0
3,50 5,00 315 3,0
A4 1.25 6,50 250 3,5
b c
AL4 1,50 3,50 3,0
325 342
b c
3,50 5,00 3,0
315 330
AL5 1,50 5,00 295 3,5
a
Depending on history, regions and standardization committees, different designations for one and the same
material properties exist with the unavoidable consequence of inconsistent designations and numbering
sequence.
b
Of individual wires.
c
Mean of a lot.
Table 4 – Minimum mechanical properties for ATx wires
Nominal wire diameter
AT1 AT2 AT3 AT4
Minimum
mm
elongation
b
after break
Up to and
Over Minimum tensile strength
including
MPa %
a a
--- 2,30 171 --- 171 --- 1,5
a a a a
2,30 2,60 169 248 169 169 1,5
2,60 2,90 166 245 166 165 1,6
2,90 3,50 162 241 162 162 1,7
3,50 3,80 162 241 162 162 1,8
3,80 4,00 159 238 159 159 1,9
4,00 5,00 159 225 159 159 2,0
5,00 5,50 155 218 155 155 2,1
a a a a
5,50 6,50 155 218 155 155 2,2
a
For nominal diameters below 2,30 mm and above 6,50 mm, the values shall be agreed between the purchaser
and the manufacturer.
b
As an option and upon agreement between purchaser and manufacturer, the minimum elongation may be set
to 1,0 % for all AT1 wire diameters due to the similarity of A1/AL1 and AT1 materials and provided the
manufacturer demonstrates the justification.

Table 5 – Temperature and duration of heating
-- AT1 AT2 AT3 AT4
Maximum allowable continuous operation
150 150 210 230
temperature (°C)
+5 +5 +5 +10
Heating temperature for 1 h exposure (°C) 230 230 280 400
-3 -3 -3 -6
Heating temperature for 400 h exposure +10 +10 +10 +10
180 180 240 310
(°C) -6 -6 -6 -6
Table 6 – Parameters for bending test of aluminium alloy wires
Number of bending Radius of cylindrical
Nominal wire diameter
cycles support
mm -- mm
Over Up to and including
1,5 2,0 5 5
2,0 2,5 4 5
2,5 2,8 7 10
2,8 3,6 6 10
3,6 4,5 6 15
4,5 5,0 5 15
– 14 – IEC 62641:2022 © IEC 2022
Annex A
(normative)
Methods of securing formed wires
Figure A.1 gives the methods of securing formed wires.

Figure A.1 – Methods of securing formed wires

Annex B
(informative)
Thermal-resistant property
B.1 Thermal-resistant properties
The thermal-resistant property of an aluminium alloy, called thermal resistivity in this document,
describes its ability to resist annealing at high temperature, and is measured by the amount of
reduction of its tensile strength after heating. This phenomenon can be experimentally
described by an Arrhenius plot, of which typical ones for several aluminium alloys have been
published. The thermal resistivity of aluminium alloy wires generally used in overhead
transmission lines is determined by an endurance equivalent (temperature and duration) to a
heating condition above room temperature, where the residual strength ratio can be maintained
to a minimum of 0,90.
For the purposes of this document, the thermal resistivity of the aluminium alloys is set by its
capability of sustaining a given temperature for a duration of 400 h while maintaining a residual
strength ratio of 0,90.
Figure B.1 – Arrhenius plot (residual strength 90 %)
B.2 Explanation of the Arrhenius plot
Each aluminium alloy can maintain a minimum of 90 % of its initial tensile strength when it is
heated at the temperature and duration (for either 1 h, 400 h, or 350 400 h) described in the
Arrhenius plot. In other words, the thermal resistivity can be verified after 400 h at a given
temperature, or in a shorter period of time but at a higher temperature, such as 1 h in terms of
the Arrhenius plot. Consequently, it is possible to extrapolate the lines for the different alloys
and estimate the temperature and duration at which the residual strength ratio can be
maintained, such as 40 years (350 400 h) in this case.

– 16 – IEC 62641:2022 © IEC 2022
B.3 Continuous operation temperature
Table 5 shows the continuous operation temperature for each thermal-resistant aluminium alloy
wire obtained from the Arrhenius plot. In reality, the duration of continuous operation applied
amounted to 36 years. However, for the purposes of this document, 350 400 h (about 40 years)
was adopted for simplification.
B.4 Duration and heating temperature
The combination of temperature and time in Table 5 have been chosen to:
– carry out the tests in shorter periods of time,
– avoid a processing effect, i.e. maintain the thermal resistivity of the material without
changing the metallic property at higher temperature,
– have results that do not exhibit a large scattering.
The relationship of the allowable temperatures for 1 h and 400 h to the allowable temperature
for a 40-year period have been determined from Figure B.1.

Bibliography
IEC 60028, International standard of resistance for copper
CIGRE TB 643, Guide to the Operation of Conventional Conductor Systems above 100 °C

___________
– 18 – IEC 62641:2022 © IEC 2022
SOMMAIRE
AVANT-PROPOS . 19
INTRODUCTION . 21
1 Domaine d'application . 22
2 Références normatives . 22
3 Termes et définitions . 22
4 Matériau . 24
5 Raccordements . 24
6 Essais . 24
6.1 Généralités . 24
6.2 Lieu d’exécution des essais . 25
6.3 Fréquence d’échantillonnage . 25
6.4 Méthodes d’essai . 25
6.4.1 Aspect . 25
6.4.2 Diamètre du fil . 25
6.4.3 Résistance à la traction . 25
6.4.4 Allongement . 26
6.4.5 Enroulement . 26
6.4.6 Flexion . 26
6.4.7 Résistivité électrique . 26
6.4.8 Résistance thermique . 27
6.5 Acceptation et rejet . 27
6.6 Certificat de conformité . 27
7 Longueur et tolérance sur longueur . 27
Annexe A (normative) Méthodes de fixation des fils de forme . 31
Annexe B (informative) Propriété de résistance à la chaleur . 32
B.1 Propriétés de résistance à la chaleur . 32
B.2 Explication du graphique d’Arrhenius . 33
B.3 Température de fonctionnement continu . 33
B.4 Durée et température de chauffage . 33
Bibliographie . 34

Figure A.1 – Méthodes de fixation des fils de forme . 31
Figure B.1 – Graphique d’Arrhenius (résistance résiduelle de 90 %) . 32

a b
Tableau 1 – Désignation et propriétés à des fins de calcul . 28
Tableau 2 – Tolérance sur le diamètre du fil . 28
Tableau 3 – Propriétés mécaniques minimales des fils Ax et ALx . 29
Tableau 4 – Propriétés mécaniques minimales des fils ATx . 30
Tableau 5 – Température et durée de chauffage . 30
Tableau 6 – Paramètres pour l’essai de flexion des fils en alliage d’aluminium . 30

COMMISSION ÉLECTROTECHNIQUE INTERNATIONALE
____________
CONDUCTEURS POUR LIGNES AÉRIENNES –
FILS D’ALUMINIUM ET EN ALLIAGE D’ALUMINIUM
POUR CONDUCTEURS TORONNÉS À COUCHES CONCENTRIQUES

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...