IEC 61156-5:2020

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

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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
...