IEC 60287-3-1:2017

Electric cables - Calculation of the current rating - Part 3-1: Operating conditions - Site reference conditions

IEC 60287-3-1:2017 is applicable to the conditions of steady-state operation of cables at all voltages, buried directly in the ground, in ducts, troughs or in steel pipes, both with and without partial drying-out of the soil, as well as cables in air. The term "steady state" is intended to mean a continuous constant current (100 % load factor) just sufficient to produce asymptotically the maximum conductor temperature, the surrounding ambient conditions being assumed constant. This document defines site reference conditions, however the general values are superseded by specific national requirements. This edition includes the following significant technical changes with respect to the previous edition:
- the updated list of national laying conditions is now covered in Annex A;
- Clause 5 about the information required from the purchaser for the selection of the appropriate type of cable has been removed.

Câbles électriques - Calcul du courant admissible - Partie 3-1: Conditions de fonctionnement - Conditions du site de référence

IEC 60287-3-1:2017 s'applique aux conditions de fonctionnement en régime permanent des câbles de toutes tensions enterrés directement dans le sol, placés dans des fourreaux, caniveaux ou tubes d'acier, avec ou sans assèchement partiel du sol, ainsi que les câbles posés à l'air libre. On entend par "régime permanent" la circulation continue d'un courant constant (facteur de charge 100 %) assez suffisant pour produire asymptotiquement la température maximale à l'âme en supposant que les conditions du milieu ambiant restent constantes. Le présent document définit les conditions du site de référence, cependant les valeurs générales sont remplacées par les exigences spécifiques nationales. Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
- la liste mise à jour des conditions de pose nationales est maintenant couverte par l'Annexe A;
- l'Article 5 relatif aux informations exigées de l'acheteur pour permettre la sélection du type approprié de câble a été supprimé.

General Information

• Status: Published
• Publication Date: 07-Jun-2017
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• ICS: 29.060.20 - Cables
• Technical Committee: TC 20 - Electric cables
• Drafting Committee: WG 19 - TC 20/WG 19
• Current Stage: PPUB - Publication issued
• Start Date: 02-Jun-2017
• Completion Date: 08-Jun-2017

Relations

• Revises: IEC 60287-3-1:1995/AMD1:1999 - Amendment 1 - Electric cables - Calculation of the current rating - Part 3: Sections on operating conditions - Section 1: Reference operating conditions and selection of cable type
• Effective Date: 05-Sep-2023
• Revises: IEC 60563 - Systematic review of IEC 563 (1976)
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 60287-3-1 ®
Edition 2.0 2017-06
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Electric cables – Calculation of the current rating –
Part 3-1: Sections on Operating conditions – Site reference operating conditions
and selection of cable type
All rights reserved. Unless otherwise specified, 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
either IEC or IEC's member National Committee in the country of the requester. If you have any questions about IEC
copyright or have an enquiry about obtaining additional rights to this publication, please contact the address below or
your local IEC member National Committee for further information.

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3, rue de Varembé Fax: [phone]
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Switzerland www.iec.ch
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About IEC publications
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IEC 60287-3-1 ®
Edition 2.0 2017-06
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Electric cables – Calculation of the current rating –

Part 3-1: Sections on Operating conditions – Site reference operating conditions

and selection of cable type
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.060.20 ISBN 978-2-8322-4466-1

– 2 – IEC 60287-3-1:2017 RLV © IEC 2017
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 Reference ambient temperatures and thermal resistivities of soil in various
countries . 6
4.1 Standard Operating conditions – Site reference conditions . 6
4.2 Procedure when values are not provided in national tables . 7
4.2.1 General . 7
4.2.2 Ambient temperatures at sea level . 7
4.2.3 Thermal resistivity of soil . 7
4.2.4 Solar radiation . 8
5 Information required from the purchaser for the selection of the appropriate type
of cable .
Annex A (informative) Values relating to the operating conditions in various countries . 9
A.1 Australia . 9
A.2 Austria . 10
A.3 Canada . 11
A.4 China . 12
A.5 Egypt . 12
A.6 Finland . 13
A.7 France . 14
A.8 Germany . 15
A.9 Italy . 15
A.10 Japan. 16
A.11 Mexico . 17
A.12 Netherlands . 20
A.13 New Zealand . 21
A.14 Norway . 21
A.15 Oman . 22
A.16 Poland . 22
A.17 Portugal . 23
A.18 Spain . 23
A.19 South Africa . 24
A.20 Sweden . 24
A.21 Switzerland . 25
A.22 United Kingdom . 26
A.22.1 HV . 26
A.22.2 LV/MV . 27
A.23 United States of America . 27
Bibliography . 30

Table 1 – Ambient temperatures at sea level . 7
Table 2 – Thermal resistivity of soil . 8

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ELECTRIC CABLES –
CALCULATION OF THE CURRENT RATING –

Part 3-1: Sections on Operating conditions –
Site reference operating conditions and selection of cable type

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
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other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
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9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
This redline version of the official IEC Standard allows the user to identify the changes
made to the previous edition. A vertical bar appears in the margin wherever a change
has been made. Additions are in green text, deletions are in strikethrough red text.

– 4 – IEC 60287-3-1:2017 RLV © IEC 2017
International Standard IEC 60287-3-1 has been prepared by IEC technical committee 20:
Electric cables.
This second edition cancels and replaces the first edition published in 1995 and
Amendment 1:1999. This edition constitutes a technical revision. This edition includes the
following significant technical changes with respect to the previous edition:
a) the updated list of national laying conditions is now covered in Annex A;
b) Clause 5 about the information required from the purchaser for the selection of the
appropriate type of cable has been removed.
The text of this standard is based on the following documents:
FDIS Report on voting
20/1714/FDIS 20/1730/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts in the IEC 60287 series, published under the general title Electric cables –
Calculation of the current rating, can be found on the IEC website.
The reader's attention is drawn to the fact that Annex A lists all of the “in-some-country”
clauses on differing practices of a less permanent nature relating to the subject of this
standard.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC website under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
IMPORTANT – The “colour inside” logo on the cover page of t
...

IEC 60287-3-1 ®
Edition 2.0 2017-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Electric cables – Calculation of the current rating –
Part 3-1: Operating conditions – Site reference conditions

Câbles électriques – Calcul du courant admissible –
Partie 3-1: Conditions de fonctionnement – Conditions du site de référence

All rights reserved. Unless otherwise specified, 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
either IEC or IEC's member National Committee in the country of the requester. If you have any questions about IEC
copyright or have an enquiry about obtaining additional rights to this publication, please contact the address below or
your local IEC member National Committee for further information.

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About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigenda or an amendment might have been published.

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Technical Specifications, Technical Reports and other English and French, with equivalent terms in 16 additional
documents. Available for PC, Mac OS, Android Tablets and languages. Also known as the International Electrotechnical
iPad. Vocabulary (IEV) online.

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and withdrawn publications. collected from earlier publications of IEC TC 37, 77, 86 and

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IEC 60287-3-1 ®
Edition 2.0 2017-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Electric cables – Calculation of the current rating –

Part 3-1: Operating conditions – Site reference conditions

Câbles électriques – Calcul du courant admissible –

Partie 3-1: Conditions de fonctionnement – Conditions du site de référence

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.060.20 ISBN 978-2-8322-4348-0

– 2 – IEC 60287-3-1:2017 © IEC 2017
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 Reference ambient temperatures and thermal resistivities of soil in various
countries . 6
4.1 Operating conditions – Site reference conditions . 6
4.2 Procedure when values are not provided in national tables . 7
4.2.1 General . 7
4.2.2 Ambient temperatures at sea level . 7
4.2.3 Thermal resistivity of soil . 7
4.2.4 Solar radiation . 7
Annex A (informative) Values relating to the operating conditions in various countries . 8
A.1 Australia . 8
A.2 Austria . 8
A.3 Canada . 9
A.4 China . 10
A.5 Egypt . 10
A.6 Finland . 11
A.7 France . 12
A.8 Germany . 13
A.9 Italy . 14
A.10 Japan. 14
A.11 Mexico . 14
A.12 Netherlands . 17
A.13 New Zealand . 18
A.14 Norway . 18
A.15 Oman . 19
A.16 Poland . 19
A.17 Portugal . 20
A.18 Spain . 20
A.19 South Africa . 21
A.20 Sweden . 21
A.21 Switzerland . 22
A.22 United Kingdom . 22
A.22.1 HV . 22
A.22.2 LV/MV . 23
A.23 United States of America . 23
Bibliography . 24

Table 1 – Ambient temperatures at sea level . 7
Table 2 – Thermal resistivity of soil . 7

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ELECTRIC CABLES –
CALCULATION OF THE CURRENT RATING –

Part 3-1: Operating conditions –
Site reference conditions
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and
...