EN IEC 60794-4-20:2018

SLOVENSKI STANDARD
01-januar-2019
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Optical fibre cables - Part 4-20: Sectional specification - Aerial optical cables along
electrical power lines - Family specification for ADSS (all dielectric self-supported) optical
cables (IEC 60794-4-20:2018)
Lichtwellenleiterkabel - Teil 4-20: Lichtwellenleiter-Luftkabel auf Starkstrom-Freileitungen
- Familienspezifikation für ADSS-LWL-Kabel (dielektrische, selbsttragende LWL-Kabel)
(IEC 60794-4-20:2018)
Câbles à fibres optiques - Partie 4-20: Spécification intermédiaire - Câbles optiques
aériens le long des lignes électriques de puissance - Spécification de famille pour les
câbles optiques autoporteurs entièrement diélectriques (ADSS) (IEC 60794-4-20:2018)
Ta slovenski standard je istoveten z: EN IEC 60794-4-20:2018
ICS:
33.180.10 2SWLþQDYODNQDLQNDEOL Fibres and cables
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN IEC 60794-4-20

NORME EUROPÉENNE
EUROPÄISCHE NORM
November 2018
ICS 33.180.10 Supersedes EN 60794-4-20:2012
English Version
Optical fibre cables - Part 4-20: Sectional specification - Aerial
optical cables along electrical power lines - Family specification
for ADSS (all dielectric self-supported) optical cables
(IEC 60794-4-20:2018)
Câbles à fibres optiques - Partie 4-20: Spécification Lichtwellenleiterkabel - Teil 4-20: Lichtwellenleiter-Luftkabel
intermédiaire - Câbles optiques aériens le long des lignes auf Starkstrom-Freileitungen - Familienspezifikation für
électriques de puissance - Spécification de famille pour les ADSS-LWL-Kabel (dielektrische, selbsttragende LWL-
câbles optiques autoporteurs entièrement diélectriques Kabel)
(ADSS) (IEC 60794-4-20:2018)
(IEC 60794-4-20:2018)
This European Standard was approved by CENELEC on 2018-10-02. 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, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, 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
© 2018 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN IEC 60794-4-20:2018 E

European foreword
The text of document 86A/1867/FDIS, future edition 2 of IEC 60794-4-20, prepared by SC 86A "Fibres
and cables" of IEC/TC 86 "Fibre optics" was submitted to the IEC-CENELEC parallel vote and
approved by CENELEC as EN IEC 60794-4-20:2018.
The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2019-07-02
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2021-10-02
document have to be withdrawn
This document supersedes EN 60794-4-20:2012.
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.
Endorsement notice
The text of the International Standard IEC 60794-4-20:2018 was approved by CENELEC as a
European Standard without any modification.
In the official version, for Bibliography, the following notes have to be added for the standards
indicated:
IEC 60060-1:2010 NOTE Harmonized as EN 60060-1:2010 (not modified)
IEC 60794-1-2 NOTE Harmonized as EN 60794-1-2
IEC 60794-3-20 NOTE Harmonized as EN 60794-3-20
IEC 60794-4 series NOTE Harmonized as EN 60794-4 series
IEC 61395 NOTE Harmonized as EN 61395
IEC 61935 series NOTE Harmonized as EN 61935 series

Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
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.
NOTE 1  Where an International Publication has been modified by common modifications, indicated by (mod), the relevant
EN/HD applies.
NOTE 2  Up-to-date information on the latest versions of the European Standards listed in this annex is available here:
www.cenelec.eu.
Publication Year Title EN/HD Year
IEC 60793-2 -  Optical fibres - Part 2: Product EN 60793-2 -
specifications - General
IEC 60793-2-50 -  Optical fibres - Part 2-50: Product EN 60793-2-50 -
specifications - Sectional specification for
class B single-mode fibres
IEC 60794-1-1 -  Optical fibre cables - Part 1-1: Generic EN 60794-1-1 -
specification - General
IEC 60794-1-21 2015 Optical fibre cables - Part 1-21: Generic EN 60794-1-21 2015
specification - Basic optical cable test
procedures - Mechanical tests methods
IEC 60794-1-22 -  Optical fibre cables - Part 1-22: Generic EN IEC 60794-1-22 -
specification - Basic optical cable test
procedures - Environmental test methods
IEC 60794-4 -  Optical fibre cables - Part 4: Sectional EN IEC 60794-4 -
specification - Aerial optical cables along
electrical power lines
ISO 9001 -  Quality management systems - EN ISO 9001 -
Requirements
IEC 60794-4-20 ®
Edition 2.0 2018-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Optical fibre cables –
Part 4-20: Sectional specification – Aerial optical cables along electrical power

lines – Family specification for ADSS (all dielectric self-supported) optical cables

Câbles à fibres optiques –
Partie 4-20: Spécification intermédiaire – Câbles optiques aériens le long des

lignes électriques de puissance – Spécification de famille pour les câbles

optiques autoporteurs entièrement diélectriques (ADSS)

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 33.180.10 ISBN 978-2-8322-5907-8

– 2 – IEC 60794-4-20:2018 © IEC 2018
CONTENTS
FOREWORD. 4
1 Scope . 6
2 Normative references . 6
3 Terms, definitions and abbreviated terms . 7
4 Optical fibres . 7
5 Cable elements . 7
6 Optical fibre cable constructions . 7
6.1 General . 7
6.2 Cable protection elements . 7
7 Main requirements for installation and operating conditions . 8
8 Cable design considerations . 8
9 Cable tests . 9
9.1 General . 9
9.2 Tensile performance . 9
9.2.1 General . 9
9.2.2 Family requirement . 9
9.2.3 Test conditions . 9
9.3 Sheave test . 9
9.3.1 General . 9
9.3.2 Family requirement . 9
9.3.3 Test conditions . 9
9.4 Repeated bending . 10
9.4.1 General . 10
9.4.2 Family requirements . 10
9.4.3 Test conditions . 10
9.5 Impact . 10
9.5.1 General . 10
9.5.2 Family requirements . 10
9.5.3 Test conditions . 10
9.6 Crush . 10
9.6.1 General . 10
9.6.2 Test requirements . 11
9.6.3 Test conditions . 11
9.7 Torsion . 11
9.7.1 General . 11
9.7.2 Test requirements . 11
9.8 Aeolian vibration test . 11
9.8.1 General . 11
9.8.2 Family requirements . 11
9.8.3 Test conditions . 11
9.8.4 Parameters to be reported . 11
9.9 Low frequency vibration test (galloping test) . 12
9.9.1 General . 12
9.9.2 Family requirements . 12
9.9.3 Test conditions . 12

IEC 60794-4-20:2018 © IEC 2018 – 3 –
9.10 Temperature cycling . 12
9.10.1 General . 12
9.10.2 Family requirements . 12
9.10.3 Test conditions . 12
9.11 Water penetration . 13
9.12 Cable UV resistance . 13
9.13 Tracking and erosion resistance test . 13
9.14 Creep . 13
9.15 Fitting compatibility . 14
10 Quality assurance . 14
Annex A (informative) Packaging and marking . 15
Annex B (informative) Installation considerations for ADSS cables . 16
Annex C (informative) Electrical test (tracking) . 18
C.1 General . 18
C.2 Option C2 – Sheath material qualification . 18
C.2.1 Overview . 18
C.2.2 Test arrangements . 18
C.2.3 Test procedure . 19
C.2.4 Requirements . 19
C.3 Option C3 – Pollution level and tracking resistance . 19
C.3.1 Overview . 19
C.3.2 Test setup . 20
C.3.3 Test method . 22
C.3.4 Overview of pollution model and electrical test . 22
Annex D (informative) All dielectric self-supported (ADSS) cables to be used in
overhead power lines (blank detail specification) . 24
Bibliography . 26

Figure B.1 – Example of different span lengths allowed for the same cable, depending
on sag variation . 17
Figure C.1 – Electric scheme for the test . 20
Figure C.2 – Foils of the electrodes . 20
Figure C.3 – Nozzle . 21
Figure C.4 – Details for the spraying . 21
Figure C.5 – Distributed element model with dry band arc gap . 23
Figure C.6 – Thevenin equivalent circuit . 23

Table 1 – Cable design characteristics . 8
Table 2 – Optional parameters (if required by customer) . 8
Table C.1 – R and C values for different pollution index values . 22
eq eq
Table D.1 – Blank detail specification . 24

– 4 – IEC 60794-4-20:2018 © IEC 2018
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
OPTICAL FIBRE CABLES –
Part 4-20: Sectional specification – Aerial optical cables along
electrical power lines – Family specification for ADSS
(all dielectric self-supported) optical cables

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.
International Standard IEC 60794-4-20 has been prepared by subcommittee 86A: Fibres and
cables, of IEC technical committee 86: Fibre optics.
This second edition cancels and replaces the first edition published in 2012 and constitutes a
technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) this document has been streamlined by cross-referencing IEC 60794-1-1,
IEC 60794-4 (all parts) and IEC 60794-1-2;
b) reference to the MICE table has been deleted;
c) the example of test method for particular environment in Annex C has been deleted;

IEC 60794-4-20:2018 © IEC 2018 – 5 –
The text of this International Standard is based on the following documents:
FDIS Report on voting
86A/1867/FDIS 86A/1876/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 the parts in the IEC 60794 series, published under the general title Optical fibre
cables, can be found on the IEC website.
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.
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.
– 6 – IEC 60794-4-20:2018 © IEC 2018
OPTICAL FIBRE CABLES –
Part 4-20: Sectional specification – Aerial optical cables along
electrical power lines – Family specification for ADSS
(all dielectric self-supported) optical cables

1 Scope
This part of IEC 60794-4, which is a family specification, covers optical telecommunication
cables, commonly with single-mode fibres used primarily in overhead power lines
applications. The cables can also be used in other overhead utility networks, such as for
telephony or TV services. Requirements of the sectional specification IEC 60794-4 for aerial
optical cables along electrical power lines are applicable to cables covered by this document.
This document covers the construction, mechanical, electrical, and optical performance,
installation guidelines, acceptance criteria, test requirements, environmental considerations,
and accessories compatibility for an all dielectric, self-supporting fibre optic (ADSS) cable.
This document provides construction and performance requirements that ensure, within the
guidelines of this document, that the required mechanical integrity of the cable components as
well as optical fibre mechanical reliability and transmission parameters are maintained.
The ADSS cable consists of single mode optical fibres contained in one or more protective
dielectric fibre optic units surrounded by or attached to suitable dielectric strength members
and sheaths. The cable does not contain metallic components. An ADSS cable is designed to
meet the optical and mechanical requirements under different installation, operating and
environmental conditions and loadings, as described in Annex B.
This document excludes any "lashed" or "wrapped" OPAC cables included in IEC 60794-4.
Figure 8 aerial cables are also excluded; they are specified in IEC 60794-3-20.
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 60793-2, Optical fibres – Part 2: Product specifications – General
IEC 60793-2-50, Optical fibres – Part 2-50: Product specifications – Sectional specification for
class B single-mode fibres
IEC 60794-1-1, Optical fibre cables – Part 1: Generic specification – General
IEC 60794-1-21:2015, Optical fibre cables – Part 1-21: Generic specification – Basic optical
cable test procedures – Mechanical test methods
IEC 60794-1-22, Optical fibre cables – Part 1-22: Generic specification – Basic optical cable
test procedures – Environmental test methods
___________
In some particular situations in the electrical industry, short overhead links can be also designed with
multimode fibres.
IEC 60794-4-20:2018 © IEC 2018 – 7 –
IEC 60794-4, Optical fibre cables – Part 4: Sectional specification – Aerial optical cables
along electrical power lines
ISO 9001, Quality management systems – Requirements
3 Terms, definitions and abbreviated terms
For the purposes of this document, the terms, definitions and abbreviated terms given in
IEC 60794-1-1 and IEC 60794-4 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
4 Optical fibres
Single-mode optical fibres shall be used that meet the requirements of IEC 60793-2-50. Other
types of fibre can be agreed upon between the customer and the supplier; such fibre shall
conform to IEC 60793-2. The cabled fibre shall conform to IEC 60794-4.
5 Cable elements
Refer to the relevant parts of the sectional specification IEC 60794-4.
6 Optical fibre cable constructions
6.1 General
The construction and characteristics of cable elements shall conform to IEC 60794-4. The
cable shall not contain any metallic material.
6.2 Cable protection elements
In addition to the optical unit, the cable construction may consist of the following.
a) The outer sheath shall be a weather-resistant type material. In certain conditions, it shall
be necessary to consider the use of a tracking-resistant sheath.
b) An ADSS cable shall contain self-supported systems that are integral to the cable. The
purpose of the support system is to ensure that the cable meets the optical requirements
under specified installation conditions, temperatures, and environmental loading for its
whole operating design life.
c) The basic annular construction may have strength yarns (e.g. aramid yarns) or other
dielectric strands or dielectric rods as a support structure. A single central dielectric shaft,
channelled to accommodate the optical elements, is also accepted.
d) The cable shall be designed such that fibre strain does not exceed the limit allowed by the
cable manufacturer under design tension limits of the cable (MAT). Maximum allowable
fibre strain under MAT condition shall be ≤ 0,2 % for 0,69 GPa proof-tested fibres.
NOTE In some countries, a special requirement of shotgun resistance can be specified for aerial cables. ADSS
cables covered by this document are not designed for such a condition. Cables with reinforced textile protection
could still meet the dielectric condition, but the increase in diameter and weight would make necessary a significant
enhancement of the tensile performance of the cable.

– 8 – IEC 60794-4-20:2018 © IEC 2018
7 Main requirements for installation and operating conditions
Operating conditions are particularly important for ADSS cables.
Installation and operating conditions shall be agreed between the customer and the supplier.
For the ADSS cable, a detailed study of the field conditions and a certain level of technical
support by the supplier or third-party expert should precede the agreement. Annex B provides
a general view of such considerations.
The type of fittings and hardware used to attach the ADSS to the structures shall be approved
between the customer and the supplier. Their compatibility shall be verified in accordance
with 9.15 and the fittings product specification.
8 Cable design considerations
Table 1 is a summary of cable characteristics which may be of importance as specifications to
both the customer and the supplier. Table 2 includes optional engineering parameters
relevant for the design and installation of the overhead line with an ADSS cable. Other
characteristics may be mutually agreed upon by both the customer and the supplier. A
complete blank specification is shown in Annex D.
Table 1 – Cable design characteristics
Ref. Characteristics Units
4 Number and type of fibres NA
- Modularity of cable core NA
6 Detailed description of cable construction NA
- Overall cable diameter mm
Cable weight kg/km
9.2 MAT (maximum allowable tension) kN
9-10 Allowable temperature for storage, installation and operation °C
9.3 Minimum bending diameter during installation mm
9.4 Minimum bending diameter installed mm

Table 2 – Optional parameters (if required by customer)
Ref. Characteristics Units
9.13 MIT, maximum installation (or sagging) load kN
- Modulus of elasticity MPa
-6
- Coefficient of thermal expansion 10 /°C
9.2 Fibre strain at MAT load %
Annex B Zero strain margin kN
Environmental loading conditions – Reference to local or regional installation NA
code
Recommended span and sag under MAT limit m/%
C.3 Maximum ADSS cable space potential exposure (generally specified for a low- kV
pollution environment unless specified otherwise by the customer)

IEC 60794-4-20:2018 © IEC 2018 – 9 –
9 Cable tests
9.1 General
In mechanical tests, the general optical criteria is no change in attenuation, as described in
IEC 60794-1-1 and IEC 60794-4.
In some environmental and installation tests, some increase is accepted. These are the
sheave test, the aeolian vibration test and the galloping test.
The number of fibres tested shall be representative of the cable design according to fibre
sampling indicated IEC 60794-1-1. Different sampling can be agreed between the customer
and the supplier.
The tests applicable for aerial cables are listed below. The minimum acceptance criteria for
the different designs of cables shall be indicated in the product specification.
9.2 Tensile performance
9.2.1 General
The cable should be tested in accordance with IEC 60794-1-21, method E1. Under this test,
the cables shall meet the specified MAT value.
9.2.2 Family requirement
Loaded with MAT, no change in attenuation at 1 550 nm shall be measured, and the strain in
the fibre shall be ≤ 0.2 % for 0,69 GPa proof-tested fibres. Other values can be agreed
between the customer and the supplier.
NOTE Strain limit values for fibres with different proof test values are under study.
9.2.3 Test conditions
• Test set in a straight path in accordance with Figure 1 of IEC 60794-1-21:2015 (no drums
or pulleys allowed).
• The cable shall be terminated with adequate dead-end fittings.
• Sample length of 25 m minimum.
• MAT is sustained for 1 h.
• The fibres shall be loop-back spliced so that a minimum of 100 m of fibre are under test.
9.3 Sheave test
9.3.1 General
The cable shall be tested in accordance with method E18B of IEC 60794-1-21.
9.3.2 Family requirement
Maximum permanent increase in attenuation: 0,10 dB at 1 550 nm.
No physical damage in cable elements.
9.3.3 Test conditions
• Method E18B of IEC 60794-1-21, procedure 1 or 2.
• Tension level applied during test: maximum stringing load (or MIT).
• Length of the cable: 9 m minimum. Length bent under tension: 2 m.

– 10 – IEC 60794-4-20:2018 © IEC 2018
• The cable should be terminated with the recommended dead-end fittings.
• The fibres shall be loop-back spliced so that a minimum of 100 m of fibre are under test.
• Diameter (D) of roller/cylinders ≥ manufacturer’s minimum bend diameter (approximately
≥ 40 times cable outside diameter is recommended).
• Bending angle: 45° ±15°.
• Moving speed: 1 m/s ≤ speed ≤ 10 m/s.
• Number of complete moving cycles: 20.
9.4 Repeated bending
9.4.1 General
The cable shall be tested in accordance with the method specified in IEC 60794-1-21,
method E6.
9.4.2 Family requirements
Under visual examination without magnification, there shall be no damage to the sheath or
cable elements. There shall be no change in attenuation at 1 550 nm after the completion of
the test.
9.4.3 Test conditions
• Bending radius: 20 d.
• Number of cycles: 25.
Particular conditions may be agreed between the customer and the supplier.
9.5 Impact
9.5.1 General
The cable construction shall be tested in accordance with the method specified in
IEC 60794-1-21, method E4.
9.5.2 Family requirements
Under visual examination without magnification, there shall be no damage to the sheath or to
the cable elements. The imprint of the striking surface on the sheath is not considered
mechanical damage.
There shall be no change in attenuation at 1 550 nm.
9.5.3 Test conditions
• Striking surface radius: 300 mm.
• Impact energy: 10 J.
• Number of impacts: three, each in a different place spaced not less than 500 mm apart.
NOTE these values are for general purpose use. Particular requirement could be included in product
specification.
9.6 Crush
9.6.1 General
The cable shall be tested in accordance with IEC 60794-1-21, method E3, without physical
damage or change in attenuation.

IEC 60794-4-20:2018 © IEC 2018 – 11 –
9.6.2 Test requirements
Under visual examination, there shall be no damage to the sheath or to the cable elements.
The imprint of the plate or mandrel on the sheath is not considered mechanical damage.
Long term ≥ 10 min. No change in attenuation (prior to release of load).
Short term ≥ 1 min. No change in attenuation (after test).
9.6.3 Test conditions
• Load (plate/plate): 2,2 kN for short-term load, 1,1 kN for long-term load.
• Duration of load: 1 min of short-term load, followed by 10 min of long-term load.
• Number of tests: 3.
• Spacing between test places: 500 mm.
NOTE These values are for general purpose use. Particular requirements can be included in a product
specification.
9.7 Torsion
9.7.1 General
The cable shall be tested in accordance with IEC 60794-1-21, method E7.
9.7.2 Test requirements
Under visual examination without magnification, there shall be no damage to the sheath or to
the cable elements.
No change on attenuation after the test at 1 550 nm.
9.8 Aeolian vibration test
9.8.1 General
The resistance of the cable to aeolian vibration shall be tested in accordance with
method E19 of IEC 60794-1-21.
9.8.2 Family requirements
Under visual examination without magnification, there shall be no damage to the sheath or to
the cable elements. The variation on attenuation after the test shall be no greater than
0,10 dB at 1 550 nm.
9.8.3 Test conditions
The cable should be terminated with the recommended dead-end and suspension fittings.
9.8.4 Parameters to be reported
• Length of spans.
• Length of cable and fibres tested.
• Vibration mode/characteristics maintained during the test.
• Characteristics of measuring equipment.
• Ambient temperature and humidity during the test.
• Mass/unit length and diameter of the cable.

– 12 – IEC 60794-4-20:2018 © IEC 2018
9.9 Low frequency vibration test (galloping test)
9.9.1 General
The resistance of the cable to low frequency vibration shall be tested in accordance with
IEC 60794-1-21, method E26. This test applies for ADSS cables to be installed in areas
where ice build-up and/or strong winds are envisaged.
9.9.2 Family requirements
Permanent or temporary increase in attenuation at 1 550 nm shall be ≤ 0,10 dB.
The sheath shall have no cracks or splits.
9.9.3 Test conditions
The final optical measurement shall be taken at least 2 h after the completion of the vibration
test. A section of cable from the location of the hardware support shall be loaded to the MAT,
and the attenuation shall comply with 9.2.1.
9.10 Temperature cycling
9.10.1 General
The cable shall be tested in accordance with the method specified in IEC 60794-1-22,
method F1, one-cycle procedure with the temperature limits, in accordance with operation
limits in the product specification, or combined test procedure if different storage limits are
specified.
9.10.2 Family requirements
For T and T (T and T in combined test), there shall be no change in attenuation from the
A B A1 B1
reference room temperature measurement when measured in the 1 550 nm region or at the
operational wavelength when specified by the user. T and T temperature levels are only
A1 B1
required during the last cycle.
For T and T , the change in attenuation coefficient shall be ≤ 0,15 dB/km during the last
A2 B2
cycle from the reference room temperature measurement.
On completion of the test, there shall be no change in attenuation. The measurement shall be
made in the 1 550 nm region.
9.10.3 Test conditions
• Sample length: finished cable length of at least 500 m.
• High temperature, T for one-cycle procedure (T for combined test): +60 °C.
B B1
• High temperature, T : +70 °C (only for combined test).
B2
• Low temperature, T for one-cycle procedure (T for combined test): −20 °C.
A A1
• Low temperature, T : −40 °C (only for combined test).
A2
• Rate of heating: sufficiently slow so that the effect of changing the temperature does not
cause temperature shock or 40 °C/h if not specified.
• t : enough time to get temperature stability in the sample.
• Number of cycles: 2. Additional cycles may be required depending on user requirements.
• Temperature values may vary depending on user requirements.

IEC 60794-4-20:2018 © IEC 2018 – 13 –
9.11 Water penetration
The cable shall be tested in accordance with IEC 60794-1-22, method F5B for jelly filled
cables or F5C for all-dry cables.
No water shall be detected at the unsealed end of the sample during and at the end of the
test.
9.12 Cable UV resistance
The outer sheath shall be made of UV-stabilized weather-resistant material in accordance
with IEC 60794-1-22, method F14.
Further requirements are under consideration.
9.13 Tracking and erosion resistance test
Dielectric cables installed on power lines are exposed to electrical fields. The magnitude of
this field space potential exposure depends on the line voltage, tower design, conductor
configuration, and installation location for the ADSS. Together with specific environmental
conditions, especially desert or highly polluted areas close to the sea, this can lead to
electrical degradation (e.g. dry-band arcing), which can cause severe damage to the outer
cable sheath and finally can cause a total cable failure. The sensitivity to electrical
degradation depends on a combination of the space potential, the cable, environment, and
sheath material used. In areas with higher space potentials or poor environmental conditions,
track resistant sheath materials may be essential to alleviate the risk to product life.
Experience has shown that the formerly used > 12 kV space potential transition point for
using track resistant sheath materials may be too high depending on the environmental
conditions. Under certain environmental conditions as mentioned above, tracking-resistant
sheaths may be needed with space potentials down to 4 kV. Even with tracking-resistant
sheath materials, special consideration about the feasibility of ADSS applications is required
for levels higher than 20 kV.
Tracking-resistant sheath materials shall be used in the following field conditions:
a) power lines with an operation voltage of 150 kV or higher;
b) power lines producing space potential of 4 kV or higher in salty or polluted areas.
If the ADSS cable is to be used in telecommunication poles or low-voltage distribution lines,
track-resistant requirements can be waived.
Two current options for evaluating the quality of track-resistant sheath materials are given in
Annex C:
1) salt fog method: evaluates cable in a wet condition (continuous salt water spray);
2) alternating wet dry cycles with different current levels to reflect different degrees of
resistivity resulting from varying degrees of regional environmental conditions.
Other test conditions may be needed to evaluate ADSS tracking resistance for specific
environments.
9.14 Creep
There is no pass/fail criterion for creep. This parameter is an engineering guidance to the
behaviour of the cable during its working life. The cable creep behaviour should be
determined using a test method agreed between the customer and the supplier. Suitable tests
are IEC 60794-1-21, method E32 or found in IEC 61395.

– 14 – IEC 60794-4-20:2018 © IEC 2018
9.15 Fitting compatibility
The type of fittings shall be approved between the customer and the supplier, and their
compatibility shall be verified as follows.
• Dead-end fittings shall be used during the MAT test (9.2), with a maximum of 3 mm of
displacement between the fitting and the cable during and after the test. There should be
no change in attenuation.
• A cable sample with dead-end fittings shall stand 24 h at a temperature of 60 °C ± 2 °C
and controlled RH of 85 % ± 5%, under MIT load, with a maximum displacement of 3 mm
between each fitting and cable. There should be no change in attenuation.
• Suspension fitting shall be used during vibration tests (9.8 and 9.9) with no damage to the
cable during the test. There should be no change in attenuation. Vibration dampers can
also be qualified during this test.
• Following the completed testing, the hardware fittings shall be removed and the cable's
outer sheath inspected. There shall b
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