IEC 60708:2005

INTERNATIONAL IEC
STANDARD 60708
First edition
2005-06
Low-frequency cables with polyolefin insulation
and moisture barrier polyolefin sheath

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INTERNATIONAL IEC
STANDARD 60708
First edition
2005-06
Low-frequency cables with polyolefin insulation
and moisture barrier polyolefin sheath
 IEC 2005  Copyright - all rights reserved
No part of this publication may be reproduced or utilized in any form or by any means, electronic or
mechanical, including photocopying and microfilm, without permission in writing from the publisher.
International Electrotechnical Commission, 3, rue de Varembé, PO Box 131, CH-1211 Geneva 20, Switzerland
Telephone: +41 22 919 02 11 Telefax: +41 22 919 03 00 E-mail: inmail@iec.ch Web: www.iec.ch
PRICE CODE
Commission Electrotechnique Internationale U
International Electrotechnical Commission
МеждународнаяЭлектротехническаяКомиссия
For price, see current catalogue

– 2 – 60708  IEC:2005(E)
CONTENTS
FOREWORD.4
1 Scope.6
2 Normative references .6
3 Quality assurance.7
4 Cable construction.7
4.1 Conductor .7
4.1.1 Conductor material .7
4.1.2 Type of conductor.7
4.1.3 Conductor-finish .7
4.1.4 Continuity of conductor.7
4.2 Insulation .8
4.2.1 Insulation material .8
4.2.2 Insulation thickness .8
4.2.3 Colour of insulated conductor .8
4.3 Cabling element .8
4.4 Stranding .8
4.5 Colour code.8
4.5.1 General .8
4.5.2 Sub-units, units and cables up to and including 100 pairs or
100 quads .9
4.5.3 Cables of more than 100 pairs or 100 quads.9
4.6 Spare pairs or quads .10
4.7 Filling .10
4.8 Core protection .10
4.9 Sheath .10
4.9.1 Sheath material .10
4.9.2 Application of the sheath .10
4.10 Cable protection .11
4.11 Finished cable.11
4.11.1 Overall diameter .11
4.11.2 Sheath marking .11
4.11.3 Sealing of ends .12
4.12 Delivery.12
5 Mechanical requirements.12
5.1 Conductor .12
5.2 Insulation .12
5.3 Sheath .12
5.3.1 Tensile strength and elongation.12
5.3.2 Adhesion of aluminium tape to the polyethylene .12
5.3.3 Adhesion of aluminium tape at the overlap .13
5.4 Finished cable.13
5.4.1 Sheath integrity .13
5.4.2 Resistance to water penetration .13
5.4.3 Cable drip.13

60708  IEC:2005(E) – 3 –
6 Thermal stability and environmental requirements .13
6.1 Insulation .13
6.1.1 Thermal oxidative stability (OIT-test) .13
6.1.2 Shrinkage .14
6.1.3 Wrapping test of insulation after thermal aging .14
6.1.4 Bending test at low temperature .14
6.2 Sheath .14
6.2.1 Elongation at break after ageing .14
6.2.2 Resistance to weathering .14
6.2.3 Resistance to environmental stress cracking .14
7 Electrical requirements .14
7.1 General .14
7.2 Electrical resistance of conductor .14
7.3 Electrical resistance unbalance .15
7.4 Dielectric strength .15
7.5 Insulation resistance .15
7.6 Mutual capacitance .15
7.7 Capacitance unbalance .16
7.8 Transmission characteristics (when used for digital communication).17
7.8.1 Attenuation .17
7.8.2 Near End Crosstalk (NEXT) .17
7.8.3 Equal Level Far-end Crosstalk (ELFEXT) .17
7.8.4 Power sum (PS) of crosstalk loss .17
7.8.5 Characteristic impedance .17
7.8.6 Velocity of propagation .17

Annex A (normative) Colour code: 10 pair or 5 quad count.19
Annex B (normative) Colour code: sub-unit identification for 50 pair (25 quad) and
100 pair (50 quad) cables or units, using 10 pair or 5 quad count .20
Annex C (normative) Colour code: 25 pair count .21
Annex D (normative) Colour code: unit identification for 50 pair or quad and 100 pair
or quad cables or units, using 25 pair or quad count .22
Annex E (normative) Colour code: 25 quad count .23
Annex F (normative) Colour code: unit identification for cables with more than
100 pairs, 25 pair count .24
Annex G (normative) Colour code: unit identification for cables with more than
100 pairs or 50 quads, using 10 pair or 5 quad count or 25 quad count.26

– 4 – 60708  IEC:2005(E)
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
LOW-FREQUENCY CABLES WITH POLYOLEFIN INSULATION
AND MOISTURE BARRIER POLYOLEFIN SHEATH

FOREWORD
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