IEC 62783-1:2019

IEC 62783-1 ®
Edition 1.0 2019-01
INTERNATIONAL
STANDARD
Twinax cables for digital communications –
Part 1: Generic specification
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IEC 62783-1 ®
Edition 1.0 2019-01
INTERNATIONAL
STANDARD
Twinax cables for digital communications –

Part 1: Generic specification
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 33.120.20 ISBN 978-2-8322-6249-8

– 2 – IEC 62783-1:2019 © IEC 2019
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 9
4 Requirements for cables construction . 9
4.1 General remarks . 9
4.2 Cable construction . 9
4.2.1 General . 9
4.2.2 Conductor . 9
4.2.3 Insulation . 10
4.2.4 Colour code . 10
4.2.5 Drain wire . 10
4.2.6 Screening of cable assembly element . 10
4.2.7 Cable make-up . 10
4.2.8 Screening of the cable core . 10
4.2.9 Sheath . 10
4.2.10 Colour of sheath . 11
4.2.11 Identification . 11
4.2.12 Finished cable . 11
5 Requirements and test methods . 11
5.1 General . 11
5.2 Electrical tests . 12
5.2.1 Conductor resistance . 12
5.2.2 Resistance unbalance. 12
5.2.3 Dielectric strength . 12
5.2.4 Insulation resistance . 12
5.2.5 Mutual capacitance . 12
5.2.6 Surface transfer impedance . 12
5.3 Transmission requirements and tests . 12
5.3.1 General . 12
5.3.2 Characteristic impedance . 13
5.3.3 Return loss . 13
5.3.4 Attenuation . 13
5.3.5 Propagation delay, inter-element delay skew, and intra-element delay
skew . 14
5.3.6 Near-end crosstalk (NEXT) . 14
5.3.7 Attenuation to crosstalk ratio far-end (ACR-F) . 15
5.3.8 Transverse conversion loss (TCL) . 15
5.3.9 Equal level transverse conversion transfer loss (ELTCTL) . 15
5.3.10 Screening attenuation . 15
5.3.11 Coupling attenuation . 15
5.4 Mechanical and dimensional requirements and test methods . 15
5.4.1 General . 15
5.4.2 Measurement of dimensions . 15
5.4.3 Elongation at break of the conductor. 16
5.4.4 Tensile strength of the insulation . 16

5.4.5 Elongation at break of the sheath . 16
5.4.6 Tensile strength of the sheath . 16
5.4.7 Crush test of the cable . 16
5.4.8 Impact test of the cable . 16
5.4.9 Repeated bending of the cable . 16
5.4.10 Tensile performance of the cable . 16
5.5 Environmental tests . 16
5.5.1 Shrinkage of the insulation . 16
5.5.2 Wrapping test of the insulation after thermal ageing . 16
5.5.3 Bending test of the insulation at low temperature . 16
5.5.4 Tensile strength and elongation of the sheath after ageing . 16
5.5.5 Sheath pressure test at high temperature . 16
5.5.6 Cold bend test of the cable . 17
5.5.7 Heat shock test . 17
5.5.8 Flame propagation characteristics of a single cable . 17
5.5.9 Flame propagation characteristics of bunched cables . 17
5.5.10 Smoke generation . 17
5.5.11 Combined flame and smoke test for cables in environmental air
handling spaces . 17
Bibliography . 18

Table 1 – Nominal attenuation values, dB/10 m . 13

– 4 – IEC 62783-1:2019 © IEC 2019
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
TWINAX CABLES FOR DIGITAL COMMUNICATIONS –

Part 1: Generic specification
FOREWORD
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