IEC 61156-6:2007

INTERNATIONAL IEC
STANDARD 61156-6
Second edition
2007-06
Multicore and symmetrical pair/quad
cables for digital communications –
Part 6:
Symmetrical pair/quad cables with
transmission characteristics up to 1 000 MHz –
Work area wiring – Sectional specification

Reference number
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form

or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from
either IEC or IEC's member National Committee in the country of the requester.
If you have any questions about IEC copyright or have an enquiry about obtaining additional rights to this publication,
please contact the address below or your local IEC member National Committee for further information.

IEC Central Office
3, rue de Varembé
CH-1211 Geneva 20
Switzerland
Email: inmail@iec.ch
Web: www.iec.ch
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigenda or an amendment might have been published.
ƒ Catalogue of IEC publications: www.iec.ch/searchpub
The IEC on-line Catalogue enables you to search by a variety of criteria (reference number, text, technical committee,…).
It also gives information on projects, withdrawn and replaced publications.
ƒ IEC Just Published: www.iec.ch/online_news/justpub
Stay up to date on all new IEC publications. Just Published details twice a month all new publications released. Available
on-line and also by email.
ƒ Customer Service Centre: www.iec.ch/webstore/custserv
If you wish to give us your feedback on this publication or need further assistance, please visit the Customer Service
Centre FAQ or contact us:
Email: csc@iec.ch
Tel.: +41 22 919 02 11
Fax: +41 22 919 03 00
INTERNATIONAL IEC
STANDARD 61156-6
Second edition
2007-06
Multicore and symmetrical pair/quad
cables for digital communications –
Part 6:
Symmetrical pair/quad cables with
transmission characteristics up to 1 000 MHz –
Work area wiring – Sectional specification

PRICE CODE
Commission Electrotechnique Internationale R
International Electrotechnical Commission
МеждународнаяЭлектротехническаяКомиссия
For price, see current catalogue

– 2 – 61156-6 © IEC:2007(E)
CONTENTS
FOREWORD.4

1 Scope.6

2 Normative references .6

3 Terms and definitions .7

4 Installation considerations .7

4.1 General .7

4.2 Climatic conditions .7
5 Materials and cable construction .7
5.1 General remarks.7
5.2 Cable construction .7
5.2.1 Conductor.7
5.2.2 Insulation.7
5.2.3 Cable element .7
5.2.4 Cable make-up .8
5.2.5 Screening of the cable core .8
5.2.6 Sheath.8
5.2.7 Identification.8
5.2.8 Finished cable .8
6 Characteristics and requirements .8
6.1 General remarks.8
6.2 Electrical characteristics and tests .9
6.2.1 Conductor resistance.9
6.2.2 Resistance unbalance .9
6.2.3 Dielectric strength .9
6.2.4 Insulation resistance.9
6.2.5 Mutual capacitance.9
6.2.6 Capacitance unbalance .9
6.2.7 Transfer impedance.9
6.2.8 Coupling attenuation.10
6.2.9 Ampacity .10
6.3 Transmission characteristics .10
6.3.1 Velocity of propagation (phase velocity) .10

6.3.2 Phase delay and differential delay (delay skew) .10
6.3.3 Attenuation .11
6.3.4 Unbalance attenuation.11
6.3.5 Near-end crosstalk (NEXT).12
6.3.6 Far-end crosstalk (FEXT) .12
6.3.7 Alien (exogenous) near-end crosstalk.13
6.3.8 Alien (exogenous) far-end crosstalk.13
6.3.9 Alien (exogenous) crosstalk of bundled cables .14
6.3.10 Mean characteristic impedance .14
6.3.11 Return loss (RL) .14
6.4 Mechanical and dimensional characteristics and requirements .14
6.4.1 Dimensional requirements .14
6.4.2 Elongation at break of the conductors.14
6.4.3 Tensile strength of the insulation .14

61156-6 © IEC:2007(E) – 3 –
6.4.4 Elongation at break of the insulation.15

6.4.5 Adhesion of the insulation to the conductor .15

6.4.6 Elongation at break of the sheath .15

6.4.7 Tensile strength of the sheath .15

6.4.8 Crush test of the cable .15

6.4.9 Impact test of the cable .15

6.4.10 Bending under tension.15

6.4.11 Repeated bending of the cable .15

6.4.12 Tensile performance of the cable.15

6.4.13 Shock-test requirements of the cable.15

6.4.14 Bump-test requirements of the cable .15
6.4.15 Vibration-test requirements of a cable .15
6.5 Environmental characteristics.15
6.5.1 Shrinkage of insulation .15
6.5.2 Wrapping test of insulation after thermal ageing .16
6.5.3 Bending test of insulation at low temperature .16
6.5.4 Elongation at break of the sheath after ageing.16
6.5.5 Tensile strength of the sheath after ageing .16
6.5.6 Sheath pressure test at high temperature .16
6.5.7 Cold bend test of the cable .16
6.5.8 Heat shock test.16
6.5.9 Damp heat steady state.16
6.5.10 Solar radiation .16
6.5.11 Solvents and contaminating fluids.16
6.5.12 Salt mist and sulphur dioxide.16
6.5.13 Water immersion .16
6.5.14 Hygroscopicity.16
6.5.15 Wicking .16
6.5.16 Flame propagation characteristics of a single cable.17
6.5.17 Flame propagation characteristics of bunched cables .17
6.5.18 Halogen gas evolution .17
6.5.19 Smoke generation .17
6.5.20 Toxic gas emission .17
6.5.21 Integrated fire test .17
7 Introduction to the blank detail specification .17

Bibliography.18

Table 1 – Cable categories .6
Table 2 – Transfer impedance .10
Table 3 – Coupling attenuation .10
Table 4 – Attenuation, constant values .11
Table 5 – Near-end unbalance attenuation.12
Table 6 – Worst-pair PS NEXT values .12
Table 7 – Worst-pair PS EL FEXT .13
Table 8 – PS ANEXT .13
Table 9 – PS AELFEXT .14
Table 10 – Return loss.14

– 4 – 61156-6 © IEC:2007(E)
INTERNATIONAL ELECTROTECHNICAL COMMISSION

____________
MULTICORE AND SYMMETRICAL PAIR/QUAD CABLES

FOR DIGITAL COMMUNICATIONS –
Part 6: Symmetrical pair/quad cables

with transmission characteristics

up to 1 000 MHz – Work area wiring –

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 d
...