IEC 60644:2009

Specification for high-voltage fuse-links for motor circuit applications

IEC 60644:2009 applies primarily to fuse-links used with motors started direct-on-line on alternating current systems of 50 Hz and 60 Hz. Standardizes time-current characteristics to formulate additional pulse withstand requirements regarding testing and to give guidance for the selection of fuse-links to be used with motors. Note: Fuse-links according to this specification should comply with the requirements of IEC 60282-1. The main changes with regard to the previous edition concern the following:
- update of the normative references;
- renewal of the figures.

Spécification relative aux éléments de remplacement à haute tension destinés à des circuits comprenant des moteurs

La CEI 60644:2009 s'applique principalement aux éléments de remplacement utilisés avec des moteurs à démarrage direct sur des réseaux en courant alternatif à 50 Hz et 60 Hz. Le but de la présente norme est de normaliser les caractéristiques temps-courant, d'établir des spécifications d'essais concernant la tenue aux impulsions et de donner des conseils pour le choix des éléments de remplacement destinés à être utilisés avec des moteurs. Note: Les éléments de remplacement répondant à cette spécification soient conformes aux exigences de la CEI 60282-1. Les changements majeurs par rapport à l'édition précédente sont les suivants:
- mise à jour des références normatives;
- reprise des figures.

General Information

• Status: Published
• Publication Date: 10-Aug-2009
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• ICS: 29.120.50 - Fuses and other overcurrent protection devices
• Technical Committee: SC 32A - High-voltage fuses
• Drafting Committee: MT 3 - TC 32/SC 32A/MT 3
• Current Stage: PPUB - Publication issued
• Start Date: 30-Nov-2009
• Completion Date: 11-Aug-2009

Relations

• Amended By: IEC 60644:2009/AMD1:2019 - Amendment 1 - Specification for high-voltage fuse-links for motor circuit applications
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 60644 ®
Edition 2.0 2009-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Specification for high-voltage fuse-links for motor circuit applications

Spécification relative aux éléments de remplacement à haute tension destinés à
des circuits comprenant des moteurs

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,
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IEC 60644 ®
Edition 2.0 2009-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Specification for high-voltage fuse-links for motor circuit applications

Spécification relative aux élements de remplacement à haute tension destinés à
des circuits comprenant des moteurs
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
M
CODE PRIX
ICS 29.120.50 ISBN 978-2-88910-241-9
– 2 – 60644 © IEC:2009
CONTENTS
FOREWORD.3
1 Scope.5
2 Normative references .5
3 Fuse-link time-current characteristics .5
4 K factor .6
5 Withstand requirements.6
6 Withstand tests.6
6.1 General .6
6.2 Test sequence No. 1 .7
6.3 Test sequence No. 2 .7
6.4 Interpretation of the test results.8
7 Information to be given to the user .8
8 Selection of fuse-links for motor circuit applications and correlation of fuse-link
characteristics with those of other components of the circuit.9
8.1 Selection of fuse-links .9
8.2 Co-ordination with other circuit components .9
Bibliography.12

Figure 1 – Diagrams of the test sequences .7
Figure 2 – Determination of K factor for fuse-links of intermediate rating of a
homogeneous series.8
Figure 3 – Characteristics relating to the protection of a motor circuit .11

60644 © IEC:2009 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SPECIFICATION FOR HIGH-VOLTAGE FUSE-LINKS
FOR MOTOR CIRCUIT APPLICATIONS

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
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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 provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with an IEC Publication.
6) All users should ensure that they have the latest edition of this publication.
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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.
International Standard IEC 60644 has been prepared by subcommittee 32A: High voltage
fuses, of IEC technical committee 32: Fuses
This second edition cancels and replaces the first edition, published in 1979, and constitutes
a technical revision.
The main changes with regard to the previous edition concern the following:
• update of the normative references;
• renewal of the figures.
– 4 – 60644 © IEC:2009
The text of this standard is based on the following documents:
CDV Report on voting
32A/267/CDV 32A/270/RVC
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.
The committee has decided that the contents of this publication will remain unchanged until
the maintenance result date indicated on the IEC web site 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.
60644 © IEC:2009 – 5 –
SPECIFICATION FOR HIGH-VOLTAGE FUSE-LINKS
FOR MOTOR CIRCUIT APPLICATIONS

1 Scope
This standard applies primarily to fuse-links used with motors started direct-on-line on
alternating current systems of 50 Hz and 60 Hz.
NOTE When motors are used with assisted starting this specification can also be applied but particular attention
should be paid to the selection of the rated current of the fuse-link (see 8.1) and the manufacturer of the fuse-link
should preferably be consulted.
Fuse-links according to this specification are intended to withstand normal service conditions
and motor starting pulses. They should comply with the requirements of IEC 60282-1.
The purpose of this standard is to standardize time-current characteristics, to formulate pulse
withstand requirements regarding testing and to give guidance regarding the selection of fuse-
links intended to be used with motors.
2 Normative references
The following referenced documents are indispensable for the application of this document.
For dated references, only the edition cited applies. For undated references, the latest edition
of the referenced document (including any amendments) applies.
IEC 60282-1:2005, High-voltage fuses – Part 1: Current-limiting fuses
3 Fuse-link time-current characteristics
Compared to fuses typically used for distribution system protection, fuses for motor circuit
protection should have:
– relatively high melting current (slow operation) in the 10 s region of the pre-arcing time-
current characteristic to give maximum withstand against motor starting current;
– relatively low melting current (fast operation) in the region below 0,1 s to give maximum
short-circuit protection to associated switching devices, cables and motors and their
terminal boxes.
Therefore pre-arcing time-current characteristics of fuse-links for motor circuit applications
shall be within the following limits:
I ≤ 100
I / I ≥ 3 for
n
f n
I > 100
4I / I ≥ for
n
f n
0,25
()
I / I ≤ 20 I 100 for all current ratings
f n n
0,1
where
I is the numerical value of the current rating, expressed in amperes, of the fuse-link;
n
– 6 – 60644 © IEC:2009
I and I are the numerical values of the pre-arcing currents, expressed in amperes,
f f
10 0,1
corresponding to 10 s
...

IEC 60644 ®
Edition 2.1 2019-09
CONSOLIDATED VERSION
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Specification for high-voltage fuse-links for motor circuit applications

Spécification relative aux éléments de remplacement à haute tension destinés à
des circuits comprenant des moteurs

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
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About the IEC
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International Standards for all electrical, electronic and related technologies.

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latest edition, a corrigendum or an amendment might have been published.

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IEC 60644 ®
Edition 2.1 2019-09
CONSOLIDATED VERSION
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Specification for high-voltage fuse-links for motor circuit applications

Spécification relative aux éléments de remplacement à haute tension destinés à

des circuits comprenant des moteurs

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.120.50 ISBN 978-2-8322-7425-5

IEC 60644 ®
Edition 2.1 2019-09
CONSOLIDATED VERSION
REDLINE VERSION
VERSION REDLINE
colour
inside
Specification for high-voltage fuse-links for motor circuit applications

Spécification relative aux éléments de remplacement à haute tension destinés à
des circuits comprenant des moteurs

– 2 – IEC 60644:2009+AMD1:2019 CSV
 IEC 2019
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Fuse-link time-current characteristics . 5
4 K factor . 6
5 Withstand requirements . 7
6 Withstand tests . 7
6.1 General . 7
6.2 Test sequence No. 1 . 7
6.3 Test sequence No. 2 . 7
6.4 Interpretation of the test results . 8
7 Information to be given to the user . 9
8 Selection of fuse-links for motor circuit applications and correlation of fuse-link
characteristics with those of other components of the circuit. 9
8.1 Selection of fuse-links .
8.2 Co-ordination with other circuit components .
Bibliography .

Figure 1 – Diagrams of the test sequences . 8
Figure 2 – Determination of K factor for fuse-links of intermediate rating of a
homogeneous series . 9
Figure 3 – Characteristics relating to the protection of a motor circuit .

 IEC 2019
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SPECIFICATION FOR HIGH-VOLTAGE FUSE-LINKS
FOR MOTOR CIRCUIT APPLICATIONS
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 provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with an IEC Publication.
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 consolidated version of the official IEC Standard and its amendment has been
prepared for user convenience.
IEC 60644 edition 2.1 contains the second edition (2009-08) [documents 32A/267/CDV
and 32A/270/RVC] and its amendment 1 (2019-09) [documents 32A/340/CDV and 32A/343/
RVC].
In this Redline version, a vertical line in the margin shows where the technical content
is modified by amendment 1. Additions are in green text, deletions are in strikethrough
red text. A separate Final version with all changes accepted is available in this
publication.
– 4 – IEC 60644:2009+AMD1:2019 CSV
 IEC 2019
International Standard IEC 60644 has been prepared by subcommittee 32A: High voltage
fuses, of IEC technical committee 32: Fuses
This second edition constitutes a technical revision.
The main changes with regard to the previous edition concern the following:
• update of the normative references;
• renewal of the figures.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
The committee has decided that the contents of the base publication and its amendment will
remain unchanged until the stability date indicated on the IEC web site 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 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.
 IEC 2019
SPECIFICATION FOR HIGH-VOLTAGE FUSE-LINKS
FOR MOTOR CIRCUIT APPLICATIONS

1 Scope
This standard applies primarily to fuse-links used with motors started direct-on-line on
alternating current systems of 50 Hz and 60 Hz.
NOTE When motors are used with assisted starting this specification can also be applied but particular attention
should be paid to the selection of the rated current of the fuse-link (see 8.1) and the manufacturer of the fuse-link
should preferably be consulted.
Fuse-links according to this specification are intended to withstand normal serv
...