IEC 61156-4:2009

IEC 61156-4 ®
Edition 3.0 2009-05
INTERNATIONAL
STANDARD
Multicore and symmetrical pair/quad cables for digital communications –
Part 4: Riser cables – Sectional specification

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IEC 61156-4 ®
Edition 3.0 2009-05
INTERNATIONAL
STANDARD
Multicore and symmetrical pair/quad cables for digital communications –
Part 4: Riser cables – Sectional specification

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
P
ICS 33.120.20 ISBN 978-2-88910-422-2
– 2 – 61156-4 © IEC:2009(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.7
2.1 Definitions .7
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.9
3.1 General remarks.9
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.10
3.3.1 Velocity of propagation (phase velocity) .10
3.3.2 Attenuation .10
3.3.3 Unbalance attenuation .11
3.3.4 Near-end crosstalk (NEXT) .11
3.3.5 Far-end crosstalk (FEXT).11
3.3.6 Characteristic impedance.12
3.3.7 Structural Return Loss (SRL) .13
3.4 Mechanical and dimensional characteristics and requirements .13
3.4.1 Dimensional requirements.13
3.4.2 Elongation at break of the conductors .13
3.4.3 Elongation at break of the insulation.13
3.4.4 Elongation at break of the sheath.13
3.4.5 Tensile strength of the sheath .13

61156-4 © IEC:2009(E) –3 –
3.4.6 Crush test of the cable.13
3.4.7 Impact test of the cable.13
3.4.8 Repeated bending of the cable.13
3.4.9 Tensile performance of the cable .13
3.5 Environmental characteristics .14
3.5.1 Shrinkage of insulation.14
3.5.2 Wrapping test of insulation after thermal ageing .14
3.5.3 Bending test of insulation at low temperature .14
3.5.4 Elongation at break of the sheath after ageing.14
3.5.5 Tensile strength of the sheath after ageing.14
3.5.6 Sheath pressure test at high temperature.14
3.5.7 Cold bend test of the cable .14
3.5.8 Heat shock test.14
3.5.9 Flame propagation characteristics of a single cable.14
3.5.10 Flame propagation characteristics of bunched cables.14
3.5.11 Acid gas evolution.14
3.5.12 Smoke generation.14
3.5.13 Toxic gas emission .15
3.5.14 Combined flame and smoke test for cables in environmental air
handling space .15
4 Introduction to the blank detail specification .15

Table 1 – constants.11
Table 2 – NEXT, PSNEXT constants .11
Table 3 – EL FEXT, IO FEXT values .12
Table 4 – Input impedance values .12
Table 5 – Function fitted impedance .12
Table 6 – Structural return loss (dB min) .13

– 4 – 61156-4 © IEC:2009(E)
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
MULTICORE AND SYMMETRICAL PAIR/QUAD CABLES
FOR DIGITAL COMMUNICATIONS –
Part 4: Riser cables –
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
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patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 61156-4 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 standard is to be read in conjunction with IEC 61156-1: 2002.
This third edition cancels and replaces the second edition published in 2003. This edition
constitutes a technical revision. This sectional specification relates to IEC 61156-1:2002. The
cables are specifically intended for riser wiring up to category 5 (class D) as defined and
specified in ISO/IEC 11801: 1995. The main changes can be found in subclauses 3.3.1.2,
3.3.2, 3.3.4, 3.3.5, 3.3.5.1, 3.3.5.2, 3.3.6 and 3.4.

61156-4 © IEC:2009(E) –5 –
The text of this standard is based on the first edition and on the following documents:
FDIS Report on voting
46C/884/FDIS 46C/892/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.
A list of all 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 – 61156-4 © IEC:2009(E)
MULTICORE AND SYMMETRICAL PAIR/QUAD CABLES
FOR DIGITAL COMMUNICATIONS –
Part 4: Riser cables –
Sectional specification
1 General
1.1 Scope
This part of IEC 61156 which is a sectional specification relates to IEC 61156-1:2002. The
cables are specifically intended for riser wiring up to category 5 (class D) as defined and
specified in ISO/IEC 11801:1995.
This specification defines individually screened or unscreened pairs/quads cables, with or
without overall common screen. When installed vertically extra length requirements may be
applicable and are defined in the relevant specifications. These cables are suitable for the
various communication systems for which the reference is given in the relevant detail
specification.
The cables covered by this sectional specification are intended to operate with voltages and
currents normally adopted for communication systems. These cables should not be connected
...