IEC 60172:2020

Test procedure for the determination of the temperature index of enamelled and tape wrapped winding wires

IEC 60172:2020 specifies, in accordance with the provisions of IEC 60216-1, a method for evaluating the temperature index of enamelled wire, varnished or unvarnished with an impregnating agent, and of tape wrapped round and rectangular wire, in air at atmospheric pressure by periodically monitoring changes in response to AC proof voltage tests. This procedure does not apply to fibre-insulated wire or wire covered with tapes containing inorganic fibres. NOTE The data obtained according to this test procedure provide the designer and development engineer with information for the selection of winding wire for further evaluation of insulation systems and equipment tests. This fifth edition cancels and replaces the fourth edition published in 2015. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition:
- revision of 3.1, definition of thermal index;
- revision of 3.3, time to failure;
- revisions to 5.1.1 for clarity and to reduce the range wire size range to which the test applies;
- revisions to 5.1.2 for tape wrapped round and enamelled or tape wrapped rectangular wire for clarity;
- revision to Clause 9 to add the correlation coefficient, r to the report.

Méthode d'essai pour la détermination de l'indice de température des fils de bobinage émaillés et enveloppés de ruban

L'IEC 60172:2020 spécifie, conformément aux dispositions de l’IEC 60216-1, une méthode pour l’évaluation de l'indice de température du fil émaillé, imprégné ou non imprégné avec un matériau d’imprégnation, et du fil de section circulaire ou rectangulaire, enveloppé de ruban, dans l’air à la pression atmosphérique, en contrôlant périodiquement les variations de réponse aux essais de tension d'épreuve en courant alternatif. Cette méthode ne concerne pas le fil avec revêtement fibreux ou le fil recouvert de rubans contenant des fibres non organiques. NOTE Les données obtenues au moyen de cette méthode d'essai fournissent à l'ingénieur d'étude et de développement les informations pour sélectionner le fil de bobinage et obtenir une meilleure évaluation des systèmes isolants et des essais d'équipement. Cette cinquième édition annule et remplace la quatrième édition parue en 2015. Cette édition constitue une révision technique. Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
- révision du 3.1, définition d’indice thermique;
- révision du 3.3, durée de fonctionnement avant défaillance;
- révisions du 5.1.1 à des fins de clarification et pour limiter la plage des dimensions de fils à laquelle l’essai s’applique;
- révisions à des fins de clarification du 5.1.2 relatif au fil de section circulaire enveloppé d'un ruban et au fil de section rectangulaire émaillé ou enveloppé d'un ruban;
- révision de l’Article 9 afin d’ajouter le coefficient de corrélation, r au rapport.

General Information

• Status: Published
• Publication Date: 22-Nov-2020
• ICS: 29.060.10 - Wires
• Technical Committee: TC 55 - Winding wires
• Drafting Committee: WG 1 - TC 55/WG 1
• Current Stage: PPUB - Publication issued
• Start Date: 27-Dec-2020
• Completion Date: 23-Nov-2020

Relations

• Revises: IEC 60172:2015 - Test procedure for the determination of the temperature index of enamelled and tape wrapped winding wires
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 60172 ®
Edition 5.0 2020-11
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Test procedure for the determination of the temperature index of enamelled and
tape wrapped winding wires
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
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IEC 60172 ®
Edition 5.0 2020-11
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Test procedure for the determination of the temperature index of enamelled and

tape wrapped winding wires
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.060.10 ISBN 978-2-8322-9123-8

– 2 – IEC 60172:2020 RLV © IEC 2020
CONTENTS
FOREWORD . 4
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 Summary of procedure . 7
5 Test specimens . 7
5.1 Preparation . 7
5.1.1 Enamelled round wire with a nominal conductor diameter of 0,224 mm
up to and including 2,65 mm Enamelled non-tape wrapped round wire . 7
5.1.2 Tape wrapped round wire and enamelled or tape wrapped rectangular
wire . 11
5.2 Varnish impregnation . 13
5.3 Notes on number of test specimens . 14
5.4 Specimen holder . 14
5.4.1 For specimens according to 5.1.1 . 14
5.4.2 For specimens according to 5.1.2 . 15
6 Temperature exposure. 15
7 Test voltage and its application . 17
8 Calculations . 17
8.1 Specimen failure time . 17
8.2 Time to failure . 18
8.3 Linearity of data . 18
8.4 Calculating and plotting thermal endurance and temperature index . 18
9 Report . 19
Annex A (normative) Method for calculation of the regression line . 20
Annex B (normative) Correlation coefficient . 25
Bibliography . 26

Figure 1 – Device used to form enamelled round wire test specimen . 8
Figure 2 – Spacer . 9
Figure 3 – Twist forming jig . 9
Figure 4 – Test specimen set up in forming jig . 10
Figure 5 – Test specimen formed with loop cut . 10
Figure 6 – Jig for bending large magnet wire, dielectric test specimen . 12
Figure 7 – Forming jig and test specimen . 13
Figure 8 – Specimen holder . 14
Figure 9 – Specimen holder and electrical connection fixture .
Figure 9 – Thermal endurance graph – Temperature index . 19
Figure A.1 – Plot of regression line based on sample calculation (Table A.2) . 24

Table 1 – Force and number of twists for specimens . 8
Table 2 – Proof voltage for round enamelled wire . 10
Table 3 – Recommended exposure times in days per cycle. 16

Table 4 – Proof voltage for tape-wrapped round and for enamelled or tape-wrapped
rectangular wire . 17
Table A.1 – Commonly used test temperatures in degrees Celsius and the

corresponding kelvins with its reciprocal and reciprocal squared values . 22
Table A.2 – Sample calculation . 23

– 4 – IEC 60172:2020 RLV © IEC 2020
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
TEST PROCEDURE FOR THE DETERMINATION OF THE TEMPERATURE
INDEX OF ENAMELLED AND TAPE WRAPPED WINDING WIRES

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 IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
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.

International Standard IEC 60172 has been prepared by IEC Technical Committee 55:
Winding wires.
This fifth edition cancels and replaces the fourth edition published in 2015. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
– revision of 3.1, definition of thermal index;
– revision of 3.3, time to failure;
– revisions to 5.1.1 for clarity and to reduce the range wire size range to which the test
applies;
– revisions to 5.1.2 for tape wrapped round and enamelled or tape wrapped rectangular wire
for clarity;
– revision to Clause 9 to add the correlation coefficient, r to the report.
The text of this International Standard is based on the following documents:
FDIS Report on voting
55/1876/FDIS 55/1893/RVD
Full information on the voting for the approval of this International Standard can be found in
the report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct
understanding of its contents. Users should therefore print this document using a
colour printer.
– 6 – IEC 60172:2020 RLV © IEC 2020
TEST PROCEDURE FOR THE DETERMINATION OF THE TEMPERATURE
INDEX OF ENAMELLED AND TAPE WRAPPED WINDING WIRES

1 Scope
This International Standard specifies, in accordance with the provisions of IEC 60216-1, a
method for evaluating the temperature index of enamelled wire, varnished or unvarnished with
an impregnating agent, and of tape wrapped round and rectangular wire, in air at atmospheric
pressure by periodically
...

IEC 60172 ®
Edition 5.0 2020-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Test procedure for the determination of the temperature index of enamelled and
tape wrapped winding wires
Méthode d’essai pour la détermination de l’indice de température des fils de
bobinage émaillés et enveloppés de ruban

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
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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 corrigendum or an amendment might have been published.

IEC publications search - webstore.iec.ch/advsearchform Electropedia - www.electropedia.org
The advanced search enables to find IEC publications by a The world's leading online dictionary on electrotechnology,
variety of criteria (reference number, text, technical containing more than 22 000 terminological entries in English
committee,…). It also gives information on projects, replaced and French, with equivalent terms in 16 additional languages.
and withdrawn publications. Also known as the International Electrotechnical Vocabulary

(IEV) online.
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Stay up to date on all new IEC publications. Just Published IEC Glossary - std.iec.ch/glossary
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IEC publications issued since 2002. Some entries have been
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IEC 60172 ®
Edition 5.0 2020-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Test procedure for the determination of the temperature index of enamelled and

tape wrapped winding wires
Méthode d’essai pour la détermination de l’indice de température des fils de

bobinage émaillés et enveloppés de ruban

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.060.10 ISBN 978-2-8322-9086-6

– 2 – IEC 60172:2020 © IEC 2020
CONTENTS
FOREWORD . 4
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 Summary of procedure . 7
5 Test specimens . 7
5.1 Preparation . 7
5.1.1 Enamelled non-tape wrapped round wire . 7
5.1.2 Tape wrapped round wire and enamelled or tape wrapped rectangular
wire . 10
5.2 Varnish impregnation . 12
5.3 Notes on number of test specimens . 13
5.4 Specimen holder . 13
5.4.1 For specimens according to 5.1.1 . 13
5.4.2 For specimens according to 5.1.2 . 13
6 Temperature exposure. 14
7 Test voltage and its application . 15
8 Calculations . 16
8.1 Specimen failure time . 16
8.2 Time to failure . 16
8.3 Linearity of data . 16
8.4 Calculating and plotting thermal endurance and temperature index . 17
9 Report . 18
Annex A (normative) Method for calculation of the regression line . 19
Annex B (normative) Correlation coefficient . 24
Bibliography . 25

Figure 1 – Device used to form enamelled round wire test specimen . 8
Figure 2 – Spacer . 8
Figure 3 – Twist forming jig . 9
Figure 4 – Test specimen set up in forming jig . 9
Figure 5 – Test specimen formed with loop cut . 10
Figure 6 – Jig for bending large magnet wire, dielectric test specimen . 11
Figure 7 – Forming jig and test specimen . 12
Figure 8 – Specimen holder . 13
Figure 9 – Thermal endurance graph – Temperature index . 17
Figure A.1 – Plot of regression line based on sample calculation (Table A.2) . 23

Table 1 – Force and number of twists for specimens . 8
Table 2 – Proof voltage for round enamelled wire . 10
Table 3 – Recommended exposure times in days per cycle. 14
Table 4 – Proof voltage for tape-wrapped round and for enamelled or tape-wrapped
rectangular wire . 15

Table A.1 – Commonly used test temperatures in degrees Celsius and the
corresponding kelvins with its reciprocal and reciprocal squared values . 21
Table A.2 – Sample calculation . 22

– 4 – IEC 60172:2020 © IEC 2020
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
TEST PROCEDURE FOR THE DETERMINATION OF THE TEMPERATURE
INDEX OF ENAMELLED AND TAPE WRAPPED WINDING WIRES

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 IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subj
...