IEC 61156-5:2020

Multicore and symmetrical pair/quad cables for digital communications - Part 5: Symmetrical pair/quad cables with transmission characteristics up to 1 000 MHz - Horizontal floor wiring - Sectional specification

IEC 61156-5:2020 describes the cables intended primarily for horizontal floor wiring as defined in ISO/IEC 11801. It covers cable designs comprising individually screened, common screened and unscreened pairs or quads. The transmission characteristics and the frequency range of the cables are specified at 20 °C. The cables covered by this document are intended to operate with voltages and currents normally encountered in communication systems Those cables are intended to be used to support the delivery of low voltage remote powering applications such as IEEE 802.3af (Power over Ethernet) or further developments for example according to IEEE 802.3at or IEEE 802.3bt. This third edition cancels and replaces the second edition published in 2009 and Amendment 1:2012. This edition includes the following significant technical changes with respect to the previous edition
- additional balance levels with respect to MICE implementation by certain cabling specifications;
- reference to current standards and technical reports with respect to measurement techniques and remote powering.

General Information

• Status: Published
• Publication Date: 02-Apr-2020
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• ICS: 33.120.20 - Wires and symmetrical cables
• Technical Committee: SC 46C - Wires and symmetric cables
• Drafting Committee: WG 7 - TC 46/SC 46C/WG 7
• Current Stage: PPUB - Publication issued
• Start Date: 06-Mar-2020
• Completion Date: 03-Apr-2020

Relations

• Revises: IEC 61156-5:2009 - Multicore and symmetrical pair/quad cables for digital communications - Part 5: Symmetrical pair/quad cables with transmission characteristics up to 1 000 MHz - Horizontal floor wiring - Sectional specification
• Effective Date: 05-Sep-2023
• Revises: IEC 61156-5:2009/COR2:2010 - Corrigendum 2 - Multicore and symmetrical pair/quad cables for digital communications - Part 5: Symmetrical pair/quad cables with transmission characteristics up to 1 000 MHz - Horizontal floor wiring - Sectional specification
• Effective Date: 05-Sep-2023
• Revises: IEC 61156-5:2009/COR1:2009 - Corrigendum 1 - Multicore and symmetrical pair/quad cables for digital communications - Part 5: Symmetrical pair/quad cables with transmission characteristics up to 1 000 MHz - Horizontal floor wiring - Sectional specification
• Effective Date: 05-Sep-2023
• Revises: IEC 61156-5:2009/AMD1:2012 - Amendment 1 - Multicore and symmetrical pair/quad cables for digital communications - Part 5: Symmetrical pair/quad cables with transmission characteristics up to 1 000 MHz - Horizontal floor wiring - Sectional specification
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 61156-5 ®
Edition 3.0 2020-04
INTERNATIONAL
STANDARD
Multicore and symmetrical pair/quad cables for digital communications –
Part 5: Symmetrical pair/quad cables with transmission characteristics
up to 1 000 MHz – Horizontal floor wiring – Sectional specification

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 Tel.: [phone]
3, rue de Varembé [e-mail]
CH-1211 Geneva 20 www.iec.ch
Switzerland
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 corrigendum or an amendment might have been published.

IEC publications search - webstore.iec.ch/advsearchform Electropedia - www.electropedia.org
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variety of criteria (reference number, text, technical containing more than 22 000 terminological entries in English
committee,…). It also gives information on projects, replaced and French, with equivalent terms in 16 additional languages.
and withdrawn publications. Also known as the International Electrotechnical Vocabulary

(IEV) online.
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details all new publications released. Available online and 67 000 electrotechnical terminology entries in English and
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IEC publications issued since 2002. Some entries have been
IEC Customer Service Centre - webstore.iec.ch/csc collected from earlier publications of IEC TC 37, 77, 86 and
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need further assistance, please contact the Customer Service

Centre: [e-mail].
IEC 61156-5 ®
Edition 3.0 2020-04
INTERNATIONAL
STANDARD
Multicore and symmetrical pair/quad cables for digital communications –

Part 5: Symmetrical pair/quad cables with transmission characteristics

up to 1 000 MHz – Horizontal floor wiring – Sectional specification

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 33.120.20 ISBN 978-2-8322-7970-0

– 2 – IEC 61156-5:2020 © IEC 2020
CONTENTS
FOREWORD . 5
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 8
4 Installation considerations . 8
4.1 General remarks . 8
4.2 Bending radius of installed cable. 8
4.3 Climatic conditions . 8
5 Materials and cable construction . 8
5.1 General remarks . 8
5.2 Cable construction . 9
5.2.1 Conductor . 9
5.2.2 Insulation . 9
5.2.3 Cable element . 9
5.2.4 Cable make-up . 9
5.2.5 Screening of the cable core . 9
5.2.6 Sheath . 9
5.2.7 Identification . 10
5.2.8 Finished cable . 10
6 Characteristics and requirements . 10
6.1 General remarks . 10
6.2 Electrical characteristics and tests . 10
6.2.1 Conductor resistance . 10
6.2.2 Resistance unbalance. 10
6.2.3 Dielectric strength . 11
6.2.4 Insulation resistance . 11
6.2.5 Mutual capacitance . 11
6.2.6 Capacitance unbalance . 11
6.2.7 Transfer impedance . 11
6.2.8 Coupling attenuation . 11
6.2.9 Current-carrying capacity . 12
6.3 Transmission characteristics . 12
6.3.1 Velocity of propagation (phase velocity) . 12
6.3.2 Phase delay and differential delay (delay skew) . 12
6.3.3 Attenuation (α) . 12
6.3.4 Unbalance attenuation (TCL) . 13
6.3.5 Near-end crosstalk (NEXT) . 14
6.3.6 Far-end crosstalk (ACR-F) . 15
6.3.7 Alien (exogenous) near-end crosstalk (ANEXT) . 15
6.3.8 Alien (exogenous) far-end crosstalk (AACR-F) . 16
6.3.9 Alien (exogenous) crosstalk of bundled cables . 16
6.3.10 Impedance . 16
6.3.11 Return loss (RL) . 16
6.4 Mechanical and dimensional characteristics and requirements . 17
6.4.1 Dimensional requirements . 17
6.4.2 Elongation at break of the conductors . 17

6.4.3 Tensile strength of the insulation . 17
6.4.4 Elongation at break of the insulation . 17
6.4.5 Adhesion of the insulation to the conductor . 17
6.4.6 Elongation at break of the sheath . 17
6.4.7 Tensile strength of the sheath . 17
6.4.8 Crush test of the cable . 17
6.4.9 Impact test of the cable . 18
6.4.10 Bending under tension . 18
6.4.11 Repeated bending of the cable . 18
6.4.12 Tensile performance of the cable . 18
6.4.13 Shock-test requirements of the cable . 18
6.4.14 Bump-test requirements of the cable . 18
6.4.15 Vibration-test requirements of the cable . 18
6.5 Environmental characteristics . 18
6.5.1 Shrinkage of insulation . 18
6.5.2 Wrapping test of insulation after thermal ageing . 18
6.5.3 Bending test of insulation at low temperature . 18
6.5.4 Elongation at break of the sheath after ageing . 18
6.5.5 Tensile strength of the sheath after ageing . 18
6.5.6 Sheath pressure test at high temperature . 19
6.5.7 Cold bend test of the cable . 19
6.5.8 Heat shock test . 19
6.5.9 Damp heat steady state . 19
6.5.10 Solar radiation (UV test) . 19
6.5.11 Solvents and contaminating fluids . 19
6.5.12 Salt mist and sulphur dioxide . 19
6.5.13 Water immersion . 19
6.5.14 Hygroscopicity . 19
6.5.15 Wicking. 19
6.5.16 Flame propagation characteristics of a single cable . 19
6.5.17 Flame propagation characteristics of bunched cables . 19
6.5.18 Halogen gas evolution . 19
6.5.19 Smoke generation . 20
6.5.20 Toxic gas emission . 20
6.5.21 Integrated fire test . 20
7 Category 5e multipair cable . 20
7.1 General . 20
7.2 Transmission . 20
8 Introduction to the blank detail specification . 20
Annex A (informative) Blank detail specification . 22
Bibliography . 27

Table 1 – Cable categories . 7
Table 2 – Transfer impedance . 11
Table 3 – Coupling attenuation in dB . 12
Table 4 – Attenuation equation constants . 13
Table 5 – Near-end unbalance attenuation . 14
Table 6 – Worst-pair PS NEXT(1) values . 15

– 4 – IEC 61156-5:2020 © IEC 2020
Table 7 – Worst-pair PS ACR-F (1) values . 15
Table 8 – PS ANEXT .
...

IEC 61156-5 ®
Edition 3.0 2020-04
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Multicore and symmetrical pair/quad cables for digital communications –
Part 5: Symmetrical pair/quad cables with transmission characteristics
up to 1 000 MHz – Horizontal floor wiring – Sectional specification

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 Tel.: [phone]
3, rue de Varembé [e-mail]
CH-1211 Geneva 20 www.iec.ch
Switzerland
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 corrigendum or an amendment might have been published.

IEC publications search - webstore.iec.ch/advsearchform Electropedia - www.electropedia.org
The advanced search enables to find IEC publications by a The world's leading online dictionary on electrotechnology,
variety of criteria (reference number, text, technical containing more than 22 000 terminological entries in English
committee,…). It also gives information on projects, replaced and French, with equivalent terms in 16 additional languages.
and withdrawn publications. Also known as the International Electrotechnical Vocabulary

(IEV) online.
IEC Just Published - webstore.iec.ch/justpublished
Stay up to date on all new IEC publications. Just Published IEC Glossary - std.iec.ch/glossary
details all new publications released. Available online and 67 000 electrotechnical terminology entries in English and
once a month by email. French extracted from the Terms and Definitions clause of
IEC publications issued since 2002. Some entries have been
IEC Customer Service Centre - webstore.iec.ch/csc collected from earlier publications of IEC TC 37, 77, 86 and
If you wish to give us your feedback on this publication or CISPR.

need further assistance, please contact the Customer Service

Centre: [e-mail].
IEC 61156-5 ®
Edition 3.0 2020-04
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Multicore and symmetrical pair/quad cables for digital communications –

Part 5: Symmetrical pair/quad cables with transmission characteristics

up to 1 000 MHz – Horizontal floor wiring – Sectional specification

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 33.120.20 ISBN 978-2-8322-8147-5

– 2 – IEC 61156-5:2020 RLV © IEC 2020
CONTENTS
FOREWORD . 5
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 8
4 Installation considerations . 8
4.1 General remarks . 8
4.2 Bending radius of installed cable. 8
4.3 Climatic conditions . 8
5 Materials and cable construction . 8
5.1 General remarks . 9
5.2 Cable construction . 9
5.2.1 Conductor . 9
5.2.2 Insulation . 9
5.2.3 Cable element . 9
5.2.4 Cable make-up . 9
5.2.5 Screening of the cable core . 9
5.2.6 Sheath . 9
5.2.7 Identification . 10
5.2.8 Finished cable . 10
6 Characteristics and requirements . 10
6.1 General remarks . 10
6.2 Electrical characteristics and tests . 10
6.2.1 Conductor resistance . 10
6.2.2 Resistance unbalance. 11
6.2.3 Dielectric strength . 11
6.2.4 Insulation resistance . 11
6.2.5 Mutual capacitance . 11
6.2.6 Capacitance unbalance . 11
6.2.7 Transfer impedance . 11
6.2.8 Coupling attenuation . 12
6.2.9 Current-carrying capacity . 13
6.3 Transmission characteristics . 13
6.3.1 Velocity of propagation (phase velocity) . 13
6.3.2 Phase delay and differential delay (delay skew) . 13
6.3.3 Attenuation (α) . 14
6.3.4 Unbalance attenuation (TCL) . 15
6.3.5 Near-end crosstalk (NEXT) . 16
6.3.6 Far-end crosstalk (FEXT ACR-F) . 16
6.3.7 Alien (exogenous) near-end crosstalk (ANEXT) . 17
6.3.8 Alien (exogenous) far-end crosstalk (AFEXT AACR-F) . 17
6.3.9 Alien (exogenous) crosstalk of bundled cables . 17
6.3.10 Impedance . 17
6.3.11 Return loss (RL) . 17
6.4 Mechanical and dimensional characteristics and requirements . 20
6.4.1 Dimensional requirements . 20
6.4.2 Elongation at break of the conductors . 20

6.4.3 Tensile strength of the insulation . 20
6.4.4 Elongation at break of the insulation . 20
6.4.5 Adhesion of the insulation to the conductor . 20
6.4.6 Elongation at break of the sheath . 20
6.4.7 Tensile strength of the sheath . 20
6.4.8 Crush test of the cable . 20
6.4.9 Impact test of the cable . 20
6.4.10 Bending under tension . 20
6.4.11 Repeated bending of the cable . 20
6.4.12 Tensile performance of the cable . 20
6.4.13 Shock-test requirements of the cable . 20
6.4.14 Bump-test requirements of the cable . 21
6.4.15 Vibration-test requirements of the cable . 21
6.5 Environmental characteristics . 21
6.5.1 Shrinkage of insulation . 21
6.5.2 Wrapping test of insulation after thermal ageing . 21
6.5.3 Bending test of insulation at low temperature . 21
6.5.4 Elongation at break of the sheath after ageing . 21
6.5.5 Tensile strength of the sheath after ageing . 21
6.5.6 Sheath pressure test at high temperature . 21
6.5.7 Cold bend test of the cable . 21
6.5.8 Heat shock test . 21
6.5.9 Damp heat steady state . 21
6.5.10 Solar radiation (UV test) . 21
6.5.11 Solvents and contaminating fluids . 22
6.5.12 Salt mist and sulphur dioxide . 22
6.5.13 Water immersion . 22
6.5.14 Hygroscopicity . 22
6.5.15 Wicking. 22
6.5.16 Flame propagation characteristics of a single cable . 22
6.5.17 Flame propagation characteristics of bunched cables . 22
6.5.18 Halogen gas evolution . 22
6.5.19 Smoke generation . 22
6.5.20 Toxic gas emission . 22
6.5.21 Integrated fire test . 22
7 Category 5e multipair cable . 22
7.1 General . 22
7.2 Transmission . 23
8 Introduction to the blank detail specification . 23
Annex A (informative) Acronyms for common cable constructions .
Annex A (informative) Blank detail specification . 26
Bibliography . 31

Figure 1 – Impedance template .
Figure A.1 – Common cable construction examples .

Table 1 – Cable categories . 7
Table 2 – Transfer impedance . 12

– 4 – IEC 61156-5:2020 RLV © IEC 2020
Table 3 – Coupling attenuation in dB . 13
Table 4 – Attenuation equation constants . 14
Table 5 – Near-end unbalance attenua
...