IEC 62783-1:2023

IEC 62783-1 ®
Edition 2.0 2023-05
INTERNATIONAL
STANDARD
Twinax cables for digital communications –
Part 1: Generic specification
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IEC 62783-1 ®
Edition 2.0 2023-05
INTERNATIONAL
STANDARD
Twinax cables for digital communications –

Part 1: Generic specification
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 33.120.20 ISBN 978-2-8322-7002-8

– 2 – IEC 62783-1:2023 © IEC 2023
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 9
4 Materials and cable construction . 9
4.1 General remarks . 9
4.2 Cable construction . 10
4.2.1 General . 10
4.2.2 Conductor . 10
4.2.3 Insulation . 10
4.2.4 Cable element . 10
4.2.5 Cable make-up . 11
4.2.6 Screening of the cable core . 11
4.2.7 Sheath . 12
4.2.8 Identification . 12
4.2.9 Finished cable . 12
5 Requirements and test methods . 13
5.1 General requirements . 13
5.2 Electrical characteristics and tests . 13
5.2.1 General . 13
5.2.2 Conductor resistance . 13
5.2.3 Resistance unbalance. 13
5.2.4 Dielectric strength . 13
5.2.5 Insulation resistance . 13
5.2.6 Surface transfer impedance . 14
5.2.7 Coupling attenuation . 14
5.3 Transmission characteristics and tests . 14
5.3.1 General . 14
5.3.2 Length . 14
5.3.3 Characteristic impedance . 15
5.3.4 Return loss . 15
5.3.5 Attenuation . 15
5.3.6 Propagation delay, inter-pair skew, and intra-pair skew . 16
5.3.7 Near-end crosstalk (NEXT) . 16
5.3.8 Differential mode to common mode conversion (Scd21) . 17
5.3.9 Equal level transverse conversion transfer loss (Scd21-Sdd21) . 17
5.4 Mechanical and dimensional requirements and test methods . 17
5.4.1 General . 17
5.4.2 Measurement of dimensions . 17
5.4.3 Elongation at break of the conductor. 17
5.4.4 Tensile strength of the insulation . 17
5.4.5 Elongation at break of the sheath . 18
5.4.6 Tensile strength of the sheath . 18
5.4.7 Crush test of the cable . 18
5.4.8 Cold impact test of the cable . 18

5.4.9 Repeated bending of the cable . 18
5.4.10 Tensile performance of the cable . 18
5.4.11 Vibration test of the cable . 18
5.5 Environmental tests . 18
5.5.1 Shrinkage of the insulation . 18
5.5.2 Wrapping test of the insulation after thermal ageing . 18
5.5.3 Bending test of the insulation at low temperature . 18
5.5.4 Tensile strength and elongation of the sheath after ageing . 18
5.5.5 Sheath pressure test at high temperature . 18
5.5.6 Cold bend test of the cable . 19
5.5.7 Heat shock test . 19
5.5.8 Damp heat steady state . 19
5.5.9 Salt mist . 19
5.5.10 Flame propagation characteristics of a single cable . 19
5.5.11 Flame propagation characteristics of bunched cables . 19
5.5.12 Halogen-free compounds test . 19
5.5.13 Smoke generation . 19
5.5.14 Combined flame and smoke test for cables in environmental air
handling spaces . 19
Bibliography . 20

– 4 – IEC 62783-1:2023 © IEC 2023
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
TWINAX CABLES FOR DIGITAL COMMUNICATIONS –

Part 1: Generic specification
FOREWORD
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IEC 62783-1 has been prepared by subcommittee 46C: Wires and symmetric cables, of IEC
technical committee 46: Cables, wires, waveguides, RF connectors, RF and microwave passive
components and accessories. It is an International Standard.
This second edition cancels and replaces the first edition published in 2019. This edition
constitutes a technical revision.
This edition includes the following significant technical changes compared with the previous
edition:
– 4.1: single
...