IEC 61156-12:2021

IEC 61156-12 ®
Edition 1.0 2021-01
INTERNATIONAL
STANDARD
Multicore and symmetrical pair/quad cables for digital communications –
Part 12: Symmetrical single pair cables with transmission characteristics up to
600 MHz – Work area wiring – Sectional specification

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IEC 61156-12 ®
Edition 1.0 2021-01
INTERNATIONAL
STANDARD
Multicore and symmetrical pair/quad cables for digital communications –

Part 12: Symmetrical single pair cables with transmission characteristics up to

600 MHz – Work area wiring – Sectional specification

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 33.120.20 ISBN 978-2-8322-9230-3

– 2 – IEC 61156-12:2021 © IEC 2021

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
5.3 Conductor . 9
5.4 Insulation . 9
5.5 Cable element . 9
5.6 Screening of the cable element . 9
5.7 Cable make-up. 9
5.8 Screening of the cable core . 9
5.9 Sheath . 9
5.10 Identification . 10
5.11 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 . 12
6.3.3 Attenuation (α) . 12
6.3.4 Unbalance attenuation (TCL and ELTCTL) . 13
6.3.5 Alien (exogenous) near-end crosstalk (PS ANEXT) . 13
6.3.6 Alien (exogenous) far-end crosstalk (PS AACR-F) . 14
6.3.7 Alien (exogenous) crosstalk of bundled cables . 14
6.3.8 Impedance . 14
6.3.9 Return loss (RL) . 14
6.4 Mechanical and dimensional characteristics and requirements . 15
6.4.1 Dimensional requirements . 15
6.4.2 Elongation at break of the conductor. 15
6.4.3 Tensile strength of the insulation . 15

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 . 16
6.4.11 Repeated bending of the cable . 16
6.4.12 Tensile performance of the cable . 16
6.4.13 Shock-test requirements of the cable . 16
6.4.14 Bump-test requirements of the cable . 16
6.4.15 Vibration-test requirements of a cable . 16
6.5 Environmental characteristics . 16
6.5.1 Shrinkage of insulation . 16
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 . 17
6.5.8 Heat shock test . 17
6.5.9 Damp heat steady state . 17
6.5.10 Solar radiation (UV test) . 17
6.5.11 Solvents and contaminating fluids . 17
6.5.12 Salt mist and sulphur dioxide . 17
6.5.13 Water immersion . 17
6.5.14 Hygroscopicity . 17
6.5.15 Wicking. 17
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 . 18
6.5.21 Integrated fire test method for cables in environmental air handling
spaces . 18
7 Bundled cable requirements . 18
7.1 General . 18
7.2 Single pairs sharing one sheath . 18
7.2.1 General . 18
7.2.2 Near-end crosstalk (NEXT) . 18
7.2.3 Attenuation to crosstalk ratio far-end (PS ACR-F) . 18
Annex A (informative) Blank detail specification . 20
Bibliography . 25

Table 1 – Transfer impedance . 11
Table 2 – Coupling attenuation . 12
Table 3 – Attenuation equation constants . 13
Table 4 – TCL requirements . 13

– 4 – IEC 61156-12:2021 © IEC 2021
Table 5 – ELTCTL requirements . 13
Table 6 – PS ANEXT requirements . 14
Table 7 – PS AACR-F requirements .
...