EN IEC 63248:2022

SLOVENSKI STANDARD
01-april-2023
Nadomešča:
SIST EN 61232:1996
SIST EN 61232:1996/A11:2002
Vodniki za nadzemne vode - Prevlečena ali prekrita kovinska žica za koncentrično
pletene vodnike (IEC 63248:2022)
Conductors for overhead lines - Coated or cladded metallic wire for concentric lay
stranded conductors (IEC 63248:2022)
Leiter für Freileitungen - Beschichtete oder ummantelte Metalldrähte für Leiter aus
konzentrisch verseilten Drähten (IEC 63248:2022)
Conductors for overhead lines - Coated or cladded metallic wire for concentric lay
stranded conductors (IEC 63248:2022)
Ta slovenski standard je istoveten z: EN IEC 63248:2022
ICS:
29.240.20 Daljnovodi Power transmission and
distribution lines
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN IEC 63248

NORME EUROPÉENNE
EUROPÄISCHE NORM May 2022
ICS 29.060.01; 29.240.20 Supersedes EN 61232:1995/corrigendum Feb. 1996,
EN 50189:2000, EN 61232:1995 + A11:2000
English Version
Conductors for overhead lines - Coated or cladded metallic wire
for concentric lay stranded conductors
(IEC 63248:2022)
Conducteurs pour lignes aériennes - Fil métallique revêtu Leiter für Freileitungen - Beschichtete oder ummantelte
ou recouvert pour conducteurs toronnés à couches Metalldrähte für Leiter aus konzentrisch verseilten Drähten
concentriques (IEC 63248:2022)
(IEC 63248:2022)
This European Standard was approved by CENELEC on 2022-04-08. CENELEC members are bound to comply with the CEN/CENELEC
Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.
Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC
Management Centre or to any CENELEC member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the
same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the
Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.

European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2022 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN IEC 63248:2022 E
European foreword
The text of document 7/715/FDIS, future edition 1 of IEC 63248, prepared by IEC/TC 7 "Overhead
electrical conductors" was submitted to the IEC-CENELEC parallel vote and approved by CENELEC
as EN IEC 63248:2022.
The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2023-04-11
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2025-04-11
document have to be withdrawn
This document supersedes EN 61232:1995 and EN 50189:2000, and all of their amendments and
corrigenda (if any).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights.
Any feedback and questions on this document should be directed to the users’ national committee. A
complete listing of these bodies can be found on the CENELEC website.
Endorsement notice
The text of the International Standard IEC 63248:2022 was approved by CENELEC as a European
Standard without any modification.

IEC 63248 ®
Edition 1.0 2022-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Conductors for overhead lines – Coated or cladded metallic wire for concentric

lay stranded conductors
Conducteurs pour lignes aériennes – Fil métallique revêtu ou recouvert pour

conducteurs toronnés à couches concentriques

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.060.01; 29.240.20 ISBN 978-2-8322-1080-7

– 2 – IEC 63248:2022 © IEC 2022
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 7
4 Material . 9
4.1 Steel . 9
4.2 Aluminium . 9
4.3 Zinc . 9
4.4 Zinc-aluminium alloy . 9
4.5 Advanced zinc-aluminium alloy . 9
5 Freedom from defects . 9
6 Joints . 10
7 Tests . 10
7.1 General . 10
7.2 Place of testing . 10
7.3 Sampling rate . 10
7.4 Test methods . 10
7.4.1 Visual test . 10
7.4.2 Diameter . 10
7.4.3 Stress at 1 % extension, tensile strength and elongation . 11
7.4.4 Ductility tests . 12
7.4.5 Coating or cladding tests . 13
7.4.6 Coefficient of linear expansion . 14
7.4.7 Resistivity . 14
7.4.8 Coating adherence heat resistance test . 15
8 Acceptance and rejection . 15
9 Certificate of compliance . 15
10 Packaging . 15
10.1 Type of packaging. 15
10.2 Length and tolerance on length . 15
Annex A (normative) Tables of properties for recommended IEC wire materials . 16
Annex B (informative) Properties of wire for calculation purposes . 31
Annex C (informative) Method to measure the equivalent diameter by volume . 33
Annex D (informative) Ratio of aluminium and steel or FeNi36 cross-sectional areas . 35
D.1 Standard ratio in cross-section . 35
D.2 Average aluminium thickness . 35
Bibliography . 37

Figure C.1 – Optical ground wire (OPGW) composed of formed aluminium-clad steel
wires . 33
Figure C.2 – Example of density measurement apparatus . 33

Table A.1 – Wire designation . 16
Table A.2 – Schedule of tests . 17

IEC 63248:2022 © IEC 2022 – 3 –
Table A.3 – Zinc-aluminium alloy ingot composition (group 4 and group 5) . 18
Table A.4 – Requirements for zinc and zinc-aluminium alloy coated steel wires
(group 1, group 4 and group 5) . 19
Table A.5 – Requirements for aluminium-clad FeNi36 wires (group 2) . 23
Table A.6 – Requirements for aluminium-clad steel wires (group 3) . 24
Table A.7 – Initial setting for determining stress at 1 % extension . 27
Table A.8 – Coating requirements for zinc and zinc-aluminium alloy coated wires . 28
Table A.9 – Cladding requirements for group 2 and group 3 wire . 29
Table A.10 – Coating heat resistance test for group 4 and group 5 wire . 29
Table A.11 – Temperatures for linear expansion test for group 2 wire . 29
Table A.12 – Minimum number of dips for zinc and zinc alloy coatings (group 1,

group 4, group 5) . 30
Table B.1 – Properties of wire for calculation purposes . 31
Table D.1 – Standard aluminium and steel or FeNi36 ratio in the cross section for
group 2 and group 3 wires . 35
Table D.2 – Average aluminium thickness . 36

– 4 – IEC 63248:2022 © IEC 2022
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
CONDUCTORS FOR OVERHEAD LINES – COATED OR CLADDED
METALLIC WIRE 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
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
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
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
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.
IEC 63248 has been prepared by IEC technical committee 7: Overhead electrical conductors.
It is an International Standard.
This first edition cancels and replaces the first edition of IEC 61232 published in 1993 and the
first edition of IEC 60888 published in 1987. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
editions of IEC 61232 and IEC 60888:
a) wire designations have been modified and grouped;
b) wires with zinc coating class 2 were removed;
c) new wire designations have been added;
d) aluminium-clad FeNi36 wires have been added;
e) advanced zinc-aluminium alloy coated steel wires have been added.

IEC 63248:2022 © IEC 2022 – 5 –
The text of this International Standard is based on the following documents:
Draft Report on voting
7/715/FDIS 7/720/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.
IMPORTANT – The "colour inside" logo on the cover page of this document 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.

– 6 – IEC 63248:2022 © IEC 2022
INTRODUCTION
The purpose of this document is to group together similar wire materials that share the same
general characteristics and therefore the same test procedures and requirements. Included in
this document are existing wire types from IEC 60888 and IEC 61232 as well as new wire
materials that are already in use around the world in new types of conductors.
Zinc coating class 2 according to IEC 60888 has not been included in this document, as the
demand for this class of zinc coating is extremely rare. Extra corrosion protection can be
provided by other means, including the use of zinc-aluminium alloy coatings.

IEC 63248:2022 © IEC 2022 – 7 –
CONDUCTORS FOR OVERHEAD LINES – COATED OR CLADDED
METALLIC WIRE FOR CONCENTRIC LAY STRANDED CONDUCTORS

1 Scope
This document specifies the properties of wires in the diameter range of, but not limited to,
1,25 mm to 5,50 mm. This document is applicable to coated or cladded metallic wires before
stranding used either as concentric lay overhead stranded conductors, or in the manufacture of
cores for concentric lay overhead stranded conductors, for power transmission purposes.
The various wire types and their designations are listed in Table A.1. For calculation purposes
the values listed in Annex B 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 Electro-technical Vocabulary (IEV) (available at
www.electropedia.org)
IEC 60468, Method of measurement of resistivity of metallic materials
ISO 752, Zinc ingots
ISO 6892-1, Metallic materials – Tensile testing – Part 1: Method of test at room temperature
ISO 7500-1, Metallic materials – Calibration and verification of static uniaxial testing machines
– Part 1: Tension/compression testing machines – Calibration and verification of the force-
measuring system
ISO 7800, Metallic materials – Wire – Simple torsion test
ISO 7801, Metallic materials – Wire – Reverse bend test
ISO 7802, Metallic materials – Wire – Wrapping test
ISO 7989-2, Steel wire and wire products – Non-ferrous metallic coatings on steel wire – Part 2:
Zinc or zinc-alloy coating
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60050 (all parts) and
the following apply.
– 8 – IEC 63248:2022 © IEC 2022
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at https://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1
cladded metallic wire
result of a process by which a metal is bonded under high pressure by co-rolling, co-extrusion,
or other, onto a wire creating a metallic bond between them
3.2
class
number attributed to aluminium-clad wires for the purpose of providing an approximate
conductivity value
3.3
coated metallic wire
result of a process by which a metal is deposited onto a wire by hot-dip or electrolytic process,
creating a chemical or metallic bond between them
3.4
equivalent diameter
diameter of a round wire, which would have the same cross sectional area as a given formed
wire
3.5
formed wire
drawn or rolled metal wire having a constant non-circular cross-section
3.6
group
designation given to wire types that share a common coating or cladding, or property, for a
similar purpose
3.7
FeNi36
grade of steel-nickel alloy designed to have a very low coefficient of thermal expansion
3.8
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.
3.9
nominal
value of a measurable property to which tolerance is applied
Note 1 to entry: Nominal values are target values.
3.10
production unit
coil, reel, spool, or other package of wire that represents a single usable length

IEC 63248:2022 © IEC 2022 – 9 –
3.11
sample
specimen or specimens removed from a production unit or units and considered to have
properties representative of a lot
3.12
specimen
length of wire removed for test purposes
3.13
zinc-aluminium alloy
mixture of zinc and aluminium coating applied onto the wire for the purpose of protecting it
against corrosion
Note 1 to entry: Some of these alloys with particular mixture are called mischmetal.
3.14
advanced zinc-aluminium alloy
zinc-aluminium alloy reaching specific requirements as specified in ISO7989-2
Note 1 to entry: Examples of advanced zinc-aluminium alloys are Zn90 % + 10 % aluminium and Zn95 % + 5 %
aluminium with 0,2 % to 0,5 % magnesium.
4 Material
4.1 Steel
The base metal shall be steel produced by the open hearth, electric furnace, or basic oxygen
process and shall be of such composition that the finished wire shall have the properties and
characteristics given in this document.
4.2 Aluminium
The aluminium used for coating or cladding shall have a minimum purity of 99,5 % and be of
sufficient quality to meet the thickness and electrical resistance requirements of this document.
4.3 Zinc
The ingot of zinc used for coating shall meet the requirements of ZN-3 in accordance with
ISO 752.
The zinc coating shall be applied by either the hot-dip or electroplating method. Unless agreed
between the purchaser and the manufacturer, the method of coating shall be at the discretion
of the manufacturer.
4.4 Zinc-aluminium alloy
The ingot of zinc-aluminium alloy used for coating shall be in accordance with Table A.3.
4.5 Advanced zinc-aluminium alloy
The ingot of advanced zinc-aluminium alloy used for coating shall be in accordance with
Table A.3.
5 Freedom from defects
The wires shall be smooth and free from all imperfections such as cracks, roughness, grooves,
inclusions and other defects which can compromise the performance of the final product.

– 10 – IEC 63248:2022 © IEC 2022
6 Joints
No joints shall be made in the finished coated or cladded wire.
Joints may be made at any stage of processing prior to final cold drawing by the electric butt-
weld or flash-welding process.
Welding equipment and procedure shall be such that it can be demonstrated that the ultimate
tensile strength of a finished wire specimen containing the welded section shall be not less than
96 % of the specified minimum stress at 1 % extension.
A welded section shall not be required to meet the stress at 1 % extension, elongation, torsion,
bend, and wrap tests. All other requirements need to be met.
No joints are allowed after heat treatment on wires, which will be used in single-wire conductors.
7 Tests
7.1 General
Tests shall be made by the manufacturer on the wires to demonstrate their conformity to this
document. Tests shall be made in accordance with Table A.2.
Tests shall be performed between 10 °C and 30 °C.
7.2 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.
7.3 Sampling rate
The specimen for tests specified in 7.4 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.
7.4 Test methods
7.4.1 Visual test
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, holes and inclusion of impurities.
7.4.2 Diameter
7.4.2.1 Unit for diameter
The nominal diameter of a wire shall be expressed in millimetres to two decimal places.
7.4.2.2 Diameter from direct measurements
The diameter of a round wire shall be the mean of two measurements at right angle taken at
the same cross-section. The measurement apparatus shall have an accuracy of at least
0,001 mm.
IEC 63248:2022 © IEC 2022 – 11 –
When tested in accordance with 7.4.2.2, the diameter shall not vary from its nominal value by
more than the appropriate value indicated in Table A.4, Table A.5, or Table A.6.
7.4.2.3 Diameter from weight measurements
The equivalent diameter of a formed wire shall be obtained from weight measurements made
on a sample not less than 1,0 m in length, and with its density as defined in Table B.1.
The equivalent diameter, D, of the formed wire shall be calculated by Formula (1).
4A
D= (1)
πρL
where:
D is the equivalent diameter of the sample in mm;
A is the weight of the sample with length L in g;
L is the length of the sample in m;
ρ
is the density of the sample in g/cm .
When tested in accordance with 7.4.2.3 the equivalent diameter shall not vary from its nominal
value by more than the tolerance value indicated in Table A.4, Table A.5, or Table A.6.
7.4.2.4 Diameter from volume measurement
Alternatively the equivalent diameter of a formed wire shall be obtained from the volume and
weight measurements as described in Annex C.
When tested in accordance with 7.4.2.4 the equivalent diameter shall not vary from its nominal
value by more than the tolerance value indicated in Table A.4, Table A.5, or Table A.6.
7.4.3 Stress at 1 % extension, tensile strength and elongation
7.4.3.1 Sample preparation
The wire samples shall be free from bends or kinks other than the curvature resulting from the
usual coiling operation. They shall be straightened before being inserted in the grips of the
tensile testing equipment with a roller type wire straightening arrangement or by any other
means designed to exert the minimum effect upon the mechanical properties of the sample.
Samples for tests shall not be less than 450 mm long and shall be fitted in the testing machine
so as to leave a free length of minimum 300 mm between the grips.
7.4.3.2 Stress at 1 % extension and tensile strength
The test shall be performed in accordance with ISO 6892-1.
The force-measuring system of the testing machine shall be calibrated in accordance with
ISO 7500-1, class 1, or better.
The rate of separation of the jaws of the testing machine shall be between 25 mm/min and
100 mm/min.
In order to obtain a straight test piece and ensure the alignment of the test piece and grip
arrangement, a preliminary load corresponding with the initial stress in accordance with
Table A.7 shall be applied.
– 12 – IEC 63248:2022 © IEC 2022
This load shall be maintained while a 250 mm gauge is marked on the sample and a suitable
extensometer applied on a 250 mm gauge length (not necessarily corresponding with the
marked gauge length).
A correction of the extension, in accordance with Table A.7, should be carried out to take into
account the effect of the preliminary load.
This load shall then be increased uniformly until the extensometer indicates an extension of
2,5 mm in 250 mm (1 % extension).
At this point the tensile testing equipment may be stopped if necessary, and the load read. The
value of stress at 1 % extension is calculated by dividing this load by the area of the wire based
on wire diameter measurements according to 7.4.2. Following this operation, the extensometer
may be removed. The specimen shall then be loaded to rupture and its tensile strength
determined.
When tested in accordance with 7.4.3.2 the wire shall conform to the requirements specified in
Table A.4, Table A.5, or Table A.6.
7.4.3.3 Elongation after break
The test shall be performed in accordance with ISO 6892-1.
The gauge length to be applied is 250 mm.
When tested in accordance with 7.4.3.3 the wire shall conform to the requirements specified in
Table A.4, Table A.5, or Table A.6.
7.4.3.4 Elongation at break
The test shall be performed in accordance with ISO 6892-1.
The gauge length to be applied is 250 mm.
When tested in accordance with 7.4.3.4 the wire shall conform to the requirements specified in
Table A.5, or Table A.6.
7.4.4 Ductility tests
7.4.4.1 Torsion test
The test shall be performed in accordance with ISO 7800.
The free length between the grips will be 100 times the nominal diameter.
The number of torsions obtained shall not be less than the value given in Table A.4, Table A.5
or Table A.6.
7.4.4.2 Wrapping test
The test shall be performed in accordance with ISO 7802.
The specimen shall be wrapped 8 turns in a close spiral around a mandrel, at a rate not
exceeding 15 turns per minute.
The mandrel diameter shall be in accordance with the value given in Table A.4, Table A.5, or
Table A.6.
IEC 63248:2022 © IEC 2022 – 13 –
When tested in accordance with 7.4.4.2, the sample shall not completely break.
7.4.4.3 Reverse bend test
The test shall be performed in accordance with ISO 7801.
The minimum number of reverse bends to be achieved shall be agreed between purchaser and
manufacturer.
NOTE In order to have a reference on the minimum achievable reverse bends one can refer
...