IEC 61156-8:2009

IEC 61156-8 ®
Edition 1.0 2009-05
INTERNATIONAL
STANDARD
Multicore and symmetrical pair/quad cables for digital communications –
Part 8: Symmetrical pair/quad cables with transmission characteristics up to
1 200 MHz – Work area wiring – Sectional specification

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IEC 61156-8 ®
Edition 1.0 2009-05
INTERNATIONAL
STANDARD
Multicore and symmetrical pair/quad cables for digital communications –
Part 8: Symmetrical pair/quad cables with transmission characteristics up to
1 200 MHz – Work area wiring – Sectional specification

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
Q
ICS 33.120.20 ISBN 978-2-88910-428-4
– 2 – 61156-8 © IEC:2009(E)
CONTENTS
FOREWORD.4
1 Scope.6
2 Normative references.6
3 Terms and definitions .6
4 Installation considerations.7
4.1 Installation conditions .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 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 .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 Current-carrying capacity .10
6.2.10 Shield resistance .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) .11
6.3.6 Far-end crosstalk (FEXT) .12
6.3.7 Alien (exogenous) near-end crosstalk .12
6.3.8 Alien (exogenous) far-end crosstalk .12
6.3.9 Alien (exogenous) crosstalk of bundled cables .12
6.3.10 Impedance.12
6.3.11 Return loss (RL).12
6.4 Mechanical and dimensional characteristics and requirements .13
6.4.1 Dimensional requirements.13
6.4.2 Elongation at break of the conductors .13

61156-8 © IEC:2009(E) – 3 –
6.4.3 Tensile strength of the insulation.13
6.4.4 Elongation at break of the insulation.13
6.4.5 Adhesion of the insulation to the conductor .13
6.4.6 Elongation at break of the sheath.13
6.4.7 Tensile strength of the sheath .13
6.4.8 Crush test of the cable.13
6.4.9 Impact test of the cable.13
6.4.10 Bending under tension .13
6.4.11 Repeated bending of the cable.13
6.4.12 Tensile performance of the cable .13
6.4.13 Shock test of the cable.14
6.4.14 Bump test of the cable .14
6.4.15 Vibration test of a cable .14
6.5 Environmental characteristics .14
6.5.1 Shrinkage of insulation.14
6.5.2 Wrapping test of insulation after thermal ageing .14
6.5.3 Bending test of insulation at low temperature .14
6.5.4 Elongation at break of the sheath after ageing.14
6.5.5 Tensile strength of the sheath after ageing.14
6.5.6 Sheath pressure test at high temperature.14
6.5.7 Cold bend test of the cable .14
6.5.8 Heat shock test.14
6.5.9 Damp heat steady state .14
6.5.10 Solar radiation .15
6.5.11 Solvents and contaminating fluids .15
6.5.12 Salt mist and sulphur dioxide .15
6.5.13 Water immersion .15
6.5.14 Hygroscopicity .15
6.5.15 Wicking .15
6.5.16 Flame propagation characteristics of a single cable.15
6.5.17 Flame propagation characteristics of bunched cables.15
6.5.18 Halogen gas evolution.15
6.5.19 Smoke generation.15
6.5.20 Toxic gas emission .15
6.5.21 Integrated fire test .15
7 Introduction to the blank detail specification .16
Bibliography .17

Table 1 – Transfer impedance.10
Table 2 – Coupling attenuation .10
Table 3 – Attenuation, constant values .11
Table 4 – Return loss (RL).12

– 4 – 61156-8 © IEC:2009(E)
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
MULTICORE AND SYMMETRICAL PAIR/QUAD CABLES
FOR DIGITAL COMMUNICATIONS –
Part 8: Symmetrical pair/quad cables
with transmission characteristics up to 1 200 MHz –
Work area wiring – Sectional specification

FOREWORD
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national electrotechnical committees (IEC National Committees). The object of IEC is to promote international co-
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3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all r
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