IEC 61156-3:2008

IEC 61156-3
Edition 3.0 2008-11
INTERNATIONAL
STANDARD
Multicore and symmetrical pair/quad cables for digital communications –
Part 3: Work area cable – Sectional specification

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IEC 61156-3
Edition 3.0 2008-11
INTERNATIONAL
STANDARD
Multicore and symmetrical pair/quad cables for digital communications –
Part 3: Work area cable – Sectional specification

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
N
ICS 33.120.20 ISBN 978-2-88910-420-8
– 2 – 61156-3 © IEC:2008(E)
CONTENTS
FOREWORD.4
1 General .6
1.1 Scope.6
1.2 Normative references .6
1.3 Installation considerations.6
2 Definitions, materials and cable construction.6
2.1 Definitions .6
2.2 Materials and cable construction.7
2.2.1 General remarks.7
2.2.2 Cable construction .7
2.2.3 Conductor.7
2.2.4 Insulation.7
2.2.5 Colour code of insulation.7
2.2.6 Cable element .7
2.2.7 Screening of the cable element .7
2.2.8 Cable make-up .8
2.2.9 Screening of the cable core.8
2.2.10 Sheath.8
2.2.11 Colour of sheath .8
2.2.12 Identification .8
2.2.13 Finished cable .8
3 Characteristics and requirements.8
3.1 General remarks.8
3.2 Electrical characteristics .9
3.2.1 Conductor resistance .9
3.2.2 Resistance unbalance.9
3.2.3 Dielectric strength.9
3.2.4 Insulation resistance .9
3.2.5 Mutual capacitance .9
3.2.6 Capacitance unbalance.9
3.2.7 Transfer impedance.9
3.3 Transmission characteristics.9
3.3.1 Velocity of propagation (phase velocity) .9
3.3.2 Attenuation .10
3.3.3 Unbalance attenuation .10
3.3.4 Near-end crosstalk (NEXT) .10
3.3.5 Characteristic impedance.11
3.3.6 Structural Return Loss (SRL) .11
3.4 Mechanical and dimensional characteristics and requirements .12
3.4.1 Dimensional requirements.12
3.4.2 Elongation at break of the conductors .12
3.4.3 Elongation at break of the insulation.12
3.4.4 Elongation at break of the sheath.12
3.4.5 Tensile strength of the sheath .12
3.4.6 Crush test of the cable.12
3.4.7 Impact test of the cable.12
3.4.8 Repeated bending of the cable.12

61156-3 © IEC:2008(E) – 3 –
3.4.9 Tensile performance of the cable .13
3.5 Environmental characteristics .13
3.5.1 Shrinkage of insulation.13
3.5.2 Wrapping test of insulation after thermal ageing .13
3.5.3 Bending test of insulation at low temperature .13
3.5.4 Elongation at break of the sheath after ageing.13
3.5.5 Tensile strength of the sheath after ageing.13
3.5.6 Sheath pressure test at high temperature.13
3.5.7 Cold bend test of the cable .13
3.5.8 Heat shock test.13
3.5.9 Flame propagation characteristics of a single cable.13
3.5.10 Flame propagation characteristics of bunched cables.13
3.5.11 Acid gas evolution.13
3.5.12 Smoke generation.14
3.5.13 Toxic gas emission .14
3.5.14 Combined flame and smoke test for cables in environmental air
handling space .14
4 Introduction to the blank detail specification .14

Table 1 – Constants .
Table 2 – NEXT, PSNEXT constants .11
Table 3 – Input impedance values .11
Table 4 – Function fitted impedance .11
Table 5 – Structural return loss (dB min) .12

– 4 – 61156-3 © IEC:2008(E)
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
MULTICORE AND SYMMETRICAL PAIR/QUAD CABLES
FOR DIGITAL COMMUNICATIONS –
Part 3: Work area cable –
Sectional specification
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
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5) IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
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6) All users should ensure that they have the latest edition of this publication.
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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.
International Standard IEC 61156-6 has been prepared by subcommittee 46C: Wires and
symmetric cables, of IEC technical committee 46: Cables, wires, waveguides, R.F. connectors,
R.F. and microwave passive components and accessories.
This third edition cancels and replaces the second edition published in 2003. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) new requirements for new cables Cat3, and Cat5 applications;
b) a better numbering in order to take into account the generic specification.

61156-3 © IEC:2008(E) – 5 –
The text of this standard is based on the first edition and on the following documents:
FDIS Report on voting
46C/864/FDIS 46C/869/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
This standard shall be read in conjunction with IEC 61156-1:2002.
The list of all the parts of the IEC 61156 series, under the general title Multicore and
symmetrical pair/quad cables for digital communications, can be found on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until the
maintenance result date indicated on the IEC web site under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed;
• withdrawn;
• replaced by a revised edition, or
• amended.
A bilingual version of this publication may be issued at a later date.

– 6 – 61156-3 © IEC:2008(E)
MULTICORE AND SYMMETRICAL PAIR/QUAD CABLES
FOR DIGITAL COMMUNICATIONS –
Part 3: Work area cable –
Sectional specification
1 General
1.1 Scope
This sectional specification relates to IEC 61156-1:2002. The cables are specifically intended
for work area wiring as defined in ISO/IEC 11801.
This
...