IEC 60269-1:2024
(Amendment)Low-voltage fuses - Part 1: General requirements
Low-voltage fuses - Part 1: General requirements
IEC 60269-1:2024 is applicable to fuses incorporating enclosed current-limiting fuse-links with rated breaking capacities of not less than 6 kA, intended for protecting power-frequency AC circuits of nominal voltages not exceeding 1 000 V or DC circuits of nominal voltages not exceeding 1 500 V.
Fusibles basse tension - Partie 1: Exigences générales
L'IEC 60269-1:2024 s'applique aux fusibles qui incorporent des éléments de remplacement limiteurs de courant à fusion enfermée dont le pouvoir de coupure assigné est supérieur ou égal à 6 kA, destinés à assurer la protection des circuits à courant alternatif à fréquence industrielle dont la tension nominale ne dépasse pas 1 000 V ou des circuits à courant continu dont la tension nominale ne dépasse pas 1 500 V.
General Information
Relations
Standards Content (Sample)
IEC 60269-1 ®
Edition 5.0 2024-08
REDLINE VERSION
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Low-voltage fuses –
Part 1: General requirements
Fusibles basse tension –
Partie 1: Exigences générales
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.
Droits de reproduction réservés. Sauf indication contraire, aucune partie de cette publication ne peut être reproduite ni
utilisée sous quelque forme que ce soit et par aucun procédé, électronique ou mécanique, y compris la photocopie et
les microfilms, sans l'accord écrit de l'IEC ou du Comité national de l'IEC du pays du demandeur. Si vous avez des
questions sur le copyright de l'IEC ou si vous désirez obtenir des droits supplémentaires sur cette publication, utilisez
les coordonnées ci-après ou contactez le Comité national de l'IEC de votre pays de résidence.
IEC Secretariat Tel.: +41 22 919 02 11
3, rue de Varembé info@iec.ch
CH-1211 Geneva 20 www.iec.ch
Switzerland
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 IEC Products & Services Portal - products.iec.ch
The advanced search enables to find IEC publications by a Discover our powerful search engine and read freely all the
variety of criteria (reference number, text, technical publications previews, graphical symbols and the glossary.
committee, …). It also gives information on projects, replaced With a subscription you will always have access to up to date
and withdrawn publications. content tailored to your needs.
IEC Just Published - webstore.iec.ch/justpublished
Electropedia - www.electropedia.org
Stay up to date on all new IEC publications. Just Published
The world's leading online dictionary on electrotechnology,
details all new publications released. Available online and once
containing more than 22 500 terminological entries in English
a month by email.
and French, with equivalent terms in 25 additional languages.
Also known as the International Electrotechnical Vocabulary
IEC Customer Service Centre - webstore.iec.ch/csc
(IEV) online.
If you wish to give us your feedback on this publication or need
further assistance, please contact the Customer Service
Centre: sales@iec.ch.
A propos de l'IEC
La Commission Electrotechnique Internationale (IEC) est la première organisation mondiale qui élabore et publie des
Normes internationales pour tout ce qui a trait à l'électricité, à l'électronique et aux technologies apparentées.
A propos des publications IEC
Le contenu technique des publications IEC est constamment revu. Veuillez vous assurer que vous possédez l’édition la
plus récente, un corrigendum ou amendement peut avoir été publié.
Recherche de publications IEC - Découvrez notre puissant moteur de recherche et consultez
webstore.iec.ch/advsearchform gratuitement tous les aperçus des publications, symboles
La recherche avancée permet de trouver des publications IEC graphiques et le glossaire. Avec un abonnement, vous aurez
en utilisant différents critères (numéro de référence, texte, toujours accès à un contenu à jour adapté à vos besoins.
comité d’études, …). Elle donne aussi des informations sur les
projets et les publications remplacées ou retirées. Electropedia - www.electropedia.org
Le premier dictionnaire d'électrotechnologie en ligne au monde,
IEC Just Published - webstore.iec.ch/justpublished
avec plus de 22 500 articles terminologiques en anglais et en
Restez informé sur les nouvelles publications IEC. Just
français, ainsi que les termes équivalents dans 25 langues
Published détaille les nouvelles publications parues.
additionnelles. Egalement appelé Vocabulaire
Disponible en ligne et une fois par mois par email.
Electrotechnique International (IEV) en ligne.
Service Clients - webstore.iec.ch/csc
Si vous désirez nous donner des commentaires sur cette
publication ou si vous avez des questions contactez-nous:
sales@iec.ch.
IEC Products & Services Portal - products.iec.ch
IEC 60269-1 ®
Edition 5.0 2024-08
REDLINE VERSION
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Low-voltage fuses –
Part 1: General requirements
Fusibles basse tension –
Partie 1: Exigences générales
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.120.50 ISBN 978-2-8322-9550-2
– 2 – IEC 60269-1:2024 RLV © IEC 2024
CONTENTS
FOREWORD . 7
INTRODUCTION .
1 General .
1 Scope and object . 11
2 Normative references . 11
3 Terms and definitions . 13
3.1 Fuses and their component parts . 13
3.2 General terms . 15
3.3 Characteristic quantities . 17
4 Conditions for operation in service . 21
4.1 General . 21
4.2 Ambient air temperature (T ) . 21
a
4.3 Altitude . 22
4.4 Atmospheric conditions . 22
4.5 Voltage . 22
4.6 Current . 22
4.7 Frequency, power factor and time constant . 22
4.7.1 Frequency . 22
4.7.2 Power factor . 22
4.7.3 Time constant (τ) . 22
4.8 Conditions of installation . 23
4.9 Utilization category class . 23
4.10 Discrimination Selectivity of fuse-links . 23
5 Classification . 23
6 Characteristics of fuses . 23
6.1 Summary of characteristics . 23
6.1.1 General . 23
6.1.2 Fuse-holders . 23
6.1.3 Fuse-links . 23
6.1.4 Complete fuses . 24
6.2 Rated voltage . 24
6.3 Rated current . 24
6.3.1 Rated current of the fuse-link . 25
6.3.2 Rated current of the fuse-holder . 25
6.4 Rated frequency (see 7.1 and 7.2) . 25
6.5 Rated power dissipation of a fuse-link and rated acceptable power
dissipation of a fuse-holder. . 26
6.6 Limits of time-current characteristics . 26
6.6.1 General . 26
6.6.2 Time-current characteristics, time-current zones . 26
6.6.3 Conventional times and currents . 26
6.6.4 Gates . 27
6.7 Breaking range and breaking capacity . 28
6.7.1 Breaking range and utilization category . 28
6.7.2 Rated breaking capacity . 29
6.8 Cut-off current and I t characteristics . 29
6.8.1 General . 29
6.8.2 Cut-off current characteristics . 29
6.8.3 I t characteristics . 29
7 Markings. 29
7.1 General . 29
7.2 Markings of fuse-holders . 29
7.3 Markings of fuse-links . 30
8 Standard conditions for construction . 30
8.1 Mechanical design . 30
8.1.1 Replacement of fuse-links . 30
8.1.2 Connections, including terminals . 31
8.1.3 Fuse-contacts . 31
8.1.4 Construction of a gauge-piece . 31
8.1.5 Mechanical strength of the fuse-link . 31
8.2 Insulating properties and suitability for isolation . 31
8.3 Temperature rise, power dissipation of the fuse-link and acceptable power
dissipation of a fuse-holder . 32
8.4 Operation . 33
8.5 Breaking capacity . 34
8.6 Cut-off current characteristic . 34
8.7 I t characteristics . 34
8.8 Overcurrent selectivity of fuse-links . 35
8.9 Protection against electric shock . 35
8.9.1 General . 35
8.9.2 Clearances and creepage distances . 36
8.9.3 Leakage currents of fuses suitable for isolation . 37
8.9.4 Additional constructional requirements for fuses fuse holders for linked
fuse-carriers, suitable for isolation . 37
8.10 Resistance to heat . 37
8.11 Mechanical strength . 38
8.12 Resistance to corrosion . 38
8.12.1 General . 38
8.12.2 Resistance to rusting . 38
8.12.3 Resistance to season cracking . 38
8.13 Resistance to abnormal heat and fire . 38
8.14 Electromagnetic compatibility . 38
9 Tests . 38
9.1 Overview. 38
9.1.1 General . 38
9.1.2 Kind of tests . 38
9.1.3 Ambient air temperature (T ) . 39
a
9.1.4 Condition of the fuse . 39
9.1.5 Arrangement of the fuse and dimensions . 39
9.1.6 Testing of fuse-links . 39
9.1.7 Testing of fuse-holders . 43
9.2 Verification of the insulating properties and of the suitability for isolation . 44
9.2.1 Arrangement of the fuse-holder . 44
9.2.2 Verification of the insulating properties . 44
– 4 – IEC 60269-1:2024 RLV © IEC 2024
9.2.3 Verification of the suitability for isolation . 45
9.2.4 Acceptability of test results . 46
9.3 Verification of temperature rise and power dissipation . 46
9.3.1 Arrangement of the fuse . 46
9.3.2 Measurement of the temperature rise . 47
9.3.3 Measurement of the power dissipation of the fuse-link . 47
9.3.4 Test method . 47
9.3.5 Acceptability of test results . 49
9.4 Verification of operation . 49
9.4.1 Arrangement of the fuse . 49
9.4.2 Ambient air temperature . 49
9.4.3 Test method and acceptability of test results . 49
9.5 Verification of the breaking capacity . 53
9.5.1 Arrangement of the fuse . 53
9.5.2 Characteristics of the test circuit . 53
9.5.3 Measuring instruments. 54
9.5.4 Calibration of test circuit . 54
9.5.5 Test method . 56
9.5.6 Ambient air temperature . 58
9.5.7 Interpretation of oscillograms . 58
9.5.8 Acceptability of test results . 58
9.6 Verification of the cut-off current characteristics . 59
9.6.1 Test method . 59
9.6.2 Acceptability of test results . 59
9.7 Verification of I t characteristics and overcurrent selectivity . 59
9.7.1 Test method . 59
9.7.2 Acceptability of test results . 59
9.7.3 Verification of compliance for fuse-links at 0,01 s . 59
9.7.4 Verification of overcurrent selectivity . 60
9.8 Verification of the degree of protection of enclosures . 60
9.9 Verification of resistance to heat . 60
9.10 Verification of non-deterioration of contacts . 60
9.10.1 General . 60
9.10.2 Arrangement of the fuse . 60
9.10.3 Test method . 60
9.10.4 Acceptability of test results . 60
9.11 Mechanical and miscellaneous tests . 61
9.11.1 Mechanical strength. 61
9.11.2 Miscellaneous tests . 61
9.12 Test of durability of markings . 64
Annex A (informative) Measurement of short-circuit power factor . 74
Annex B (informative) Calculation of pre-arcing I t values for "gG", "gM", “gD” and
“gN” "gU" fuse‑links and calculation of operating I t values at reduced voltage . 77
B.1 Evaluation of the pre-arcing I t value at 0,01 s . 77
B.2 Calculation of the value of pre-arcing I t under the conditions of test no. 2 . 77
B.3 Calculation of the value of operating I t at reduced voltage . 78
Annex C (informative) Calculation of cut-off current-time characteristic . 79
C.1 Overview. 79
C.2 Preliminary note . 79
C.3 Definition . 79
C.4 Characteristic. 80
C.5 Test condition . 80
C.6 Calculation from the measured values . 80
Annex D (informative) Effect of change of ambient temperature and surroundings on
the performance of fuse-links . 83
D.1 Effect of increase of ambient temperature . 83
D.1.1 On current rating . 83
D.1.2 On temperature rise . 83
D.1.3 On conventional fusing and non-fusing current (I and I ) . 83
f nf
D.1.4 For motor starting conditions . 83
D.2 Effect of decrease of ambient air temperature . 83
D.3 Effect of installation conditions. 83
Annex E (normative) Particular requirements for fuse-bases with screwless-type
terminals for external copper conductors. 84
E.1 Scope General . 84
E.3 Terms and definitions . 84
E.7 Marking . 85
E.8 Standard conditions for construction . 85
E.8.1 Fixed connections including terminals . 85
E.8.2 Dimensions of connectable conductors . 85
E.8.3 Connectable cross-sectional areas . 86
E.8.4 Insertion and disconnecting of conductors . 86
E.8.5 Design and construction of terminals . 86
E.8.6 Resistance to ageing . 87
E.9 Tests . 87
E.9.1 Test of reliability of terminals . 87
E.9.2 Tests of reliability of terminals for external conductors: mechanical
strength . 87
E.9.3 Cycling test. 88
Bibliography . 91
Figure 1 – Diagram illustrating the means of verification of the time-current
characteristic, using the results of the tests at the "gate" currents (example) . 65
Figure 2 – Overload curve and time-current characteristic for "a" fuse-links . 66
Figure 3 – Time-current zone for aM fuses . 67
Figure 4 – General presentation of the cut-off characteristics for a series of AC
fuse‑links . 68
Figure 5 – Typical diagram of the circuit used for breaking capacity test (see 9.5) . 69
Figure 6 – Interpretation of oscillograms taken during the AC breaking-capacity tests
(see 9.5.7) . 70
Figure 7 – Interpretation of oscillograms taken during the DC breaking-capacity tests
(see 9.5.7) . 71
Figure 8 – Glow-wire and position of the thermocouple . 72
Figure 9 – Test apparatus (example) . 73
Figure A.1 – Determination of circuit-impedance for calculation of power factor in
accordance with method I . 76
– 6 – IEC 60269-1:2024 RLV © IEC 2024
Figure C.1 – Cut-off current characteristic as a function of actual pre-arcing time . 82
Figure E.1 – Connecting samples . 89
Figure E.2 – Examples of terminals . 90
Table 1 – Standard values of AC rated voltages for fuses . 24
Table 22 – Preferred values of d.c. rated voltages for fuses .
Table 2 – Preferred values of DC rated voltages for fuses . 25
Table 3 – Conventional time and current for "gG", "gK" and "gM" fuse-links . 27
a
Table 4 – Gates for specified pre-arcing times of "gG", "gK" and "gM" fuse-links . 27
Table 5 – Gates for "aM ' fuse-links (all rated currents) . 28
Table 6 – Temperature rise limits ∆T = (T – T ) for contacts and terminals . 32
a
Table 7 – Maximum arc voltage . 34
Table 8 – Pre-arcing I t values at 0,01 s for "gG" and "gM" fuse-links . 35
Table 9 – Rated impulse withstand voltage . 36
Table 10 – Minimum clearances in air . 36
Table 11 – Minimum creepage distances . 36
Table 12 – Survey of complete tests on fuse-links and number of fuse-links to be
tested . 41
Table 13 – Survey of tests on fuse-links of smallest rated current of homogeneous
series and number of fuse-links to be tested . 42
Table 14 – Survey of tests on fuse-links of rated currents between the largest and the
smallest rated current of a homogeneous series and number of fuse-links to be tested . 43
Table 15 – Survey of complete tests on fuse-holders and number of fuse-holders to be
tested . 43
Table 16 – Test voltage . 45
Table 17 – Test voltage across the poles for the verification of the suitability for
isolation . 46
Table 18 – Cross-sectional area of copper conductors for tests corresponding to
Subclauses 9.3 and 9.4. 48
Table 19 – Cross-section areas of the copper conductors for the test of "aM" fuses . 51
Table 20 – Table for test in Subclause 9.4.3.5 . 52
Table 21 – Values for breaking-capacity tests on AC fuses . 55
Table 22 – Values for breaking-capacity tests on DC fuses . 56
Table E.1 – Connectable conductors . 86
Table E.2 – Cross-sections of copper conductors connectable to terminals . 86
Table E.3 – Pull forces . 88
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
LOW-VOLTAGE FUSES –
Part 1: General requirements
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) IEC draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). IEC takes no position concerning the evidence, validity or applicability of any claimed patent rights in
respect thereof. As of the date of publication of this document, IEC had not received notice of (a) patent(s), which
may be required to implement this document. However, implementers are cautioned that this may not represent
the latest information, which may be obtained from the patent database available at https://patents.iec.ch. 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 IEC 60269-1:2006+AMD1:2009+AMD2:2014 CSV. A vertical
bar appears in the margin wherever a change has been made. Additions are in green text,
deletions are in strikethrough red text.
– 8 – IEC 60269-1:2024 RLV © IEC 2024
IEC 60269-1 has been prepared by subcommittee 32B: Low-voltage fuses, of IEC technical
committee 32: Fuses. It is an International Standard.
This fifth edition cancels and replaces the fourth edition published in 2006, Amendment 1:2009
and Amendment 2:2014. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) New numbering, editorial corrections and normative references updated;
b) Term "discrimination" replaced by "selectivity" and "utilization category" by "utilization
class";
c) Term "fuses for authorized and unskilled persons" updated;
d) Replacement of fuse-link added;
e) Standard values for AC and DC voltages updated;
f) Rated currents 425A, 355A, and 1 600A added;
g) Marking: requirements and tests separated to the relevant subclauses;
h) Requirements for temperature rise limited to terminal temperature rise only;
i) Graphic symbol for fuse-base updated,
The text of this International Standard is based on the following documents:
Draft Report on voting
32B/748/FDIS 32B/756/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.
IEC 60269 consists of the following parts, under the general title Low-voltage fuses:
Part 1: General requirements
Part 2: Supplementary requirements for fuses for use by authorized persons (fuses mainly
for industrial application) – Examples of standardized systems of fuses A to I
Part 3: Supplementary requirements for fuses for use by unskilled persons (fuses mainly for
household or similar application) – Examples of standardized systems of fuses A to
F
Part 4: Supplementary requirements for fuse-links for the protection of semiconductor
devices
Part 5: Guidance for the application of low-voltage fuses
Part 6: Supplementary requirements for fuse-links for the protection of solar photovoltaic
energy systems
Part 7: Battery Fuses
For reasons of convenience, when a part of this publication has come from other publications,
a remark to this effect has been inserted in the text.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn, or
• revised.
IMPORTANT – The "colour inside" logo on the cover page of this document 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.
– 10 – IEC 60269-1:2024 RLV © IEC 2024
INTRODUCTION
A reorganization of the different parts of the IEC 60269 series has been carried out, in order to
simplify its use, especially by the laboratories which test the fuses.
IEC 60269-1, IEC 60269-2, IEC 60269-3 and IEC 60269-3-1 have been integrated into either
the new part 1 or the new parts 2 or 3, according to the subjects considered, so that the clauses
which deal exclusively with “fuses for authorized persons” are separated from the clauses
dealing with “fuses for unauthorized persons”.
As far as IEC 60269-4 and IEC 60269-4-1 are concerned, they have been integrated into the
new part 4 which deals with the fuse-links used for semiconductor protection.
LOW-VOLTAGE FUSES –
Part 1: General requirements
1 General
1 Scope and object
This part of IEC 60269 is applicable to fuses incorporating enclosed current-limiting fuse-links
with rated breaking capacities of not less than 6 kA, intended for protecting power-frequency
AC circuits of nominal voltages not exceeding 1 000 V or DC circuits of nominal voltages not
exceeding 1 500 V.
Subsequent parts of this standard, referred to herein, cover supplementary requirements for
such fuses intended for specific conditions of use or applications.
Fuse-links intended to be included in fuse-switch combinations according to IEC 60947-3
should also comply with the following requirements.
As far as not stated in subsequent parts for fuse-links, details of performance (see 3.2.4) on
DC circuits should be stated in the manufacturer's literature.
NOTE 1 For "a" fuse-links, details of performance (see 2.2.4) on d.c. circuits should be subject to agreement
between user and manufacturer.
NOTE 21 Modifications of, and supplements to, this document required for certain types of fuses for particular
applications – for example, certain fuses for rolling stock, or fuses for high-frequency circuits – will be covered, if
necessary, by separate standards.
NOTE 32 This document does not apply to miniature fuses, these being covered by IEC 60127.
The object of this standard series is to establish the characteristics of fuses or parts of fuses
(fuse-base, fuse-carrier, fuse-link) in such a way that they can be replaced by other fuses or
parts of fuses having the same characteristics provided that they are interchangeable as far as
their dimensions are concerned. For this purpose, this standard series refers in particular to
– the following characteristics of fuses:
• rated values;
• insulation;
• temperature rise in normal service;
• power dissipation and acceptable power dissipation;
• time/current characteristics;
• breaking capacity;
t characteristics.
• cut-off current characteristics and their I
– type test for verification of the characteristics of fuses;
– the marking of fuses.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies.
– 12 – IEC 60269-1:2024 RLV © IEC 2024
For undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 60038:1983, IEC standard voltages
IEC 60050(441):1984, International Electrotechnical Vocabulary (IEV) – Chapter 441:
Switchgear, controlgear and fuses
Amendment 1 (2000)
IEC 60228:2004, Conductors of insulated cables
IEC 60269-2, Low-voltage fuses – Part 2: Supplementary requirements for fuses for use by
authorized persons (fuses mainly for industrial application) – Examples of standardized systems
of fuses A to I) K
IEC 60269-3, Low-voltage fuses – Part 3: Supplementary requirements for fuses for use by
unskilled persons (fuses mainly for household or similar application) – Examples of
standardized systems of fuses A to F
IEC 60269-4, Low-voltage fuses – Part 4: Supplementary requirements for fuse-links for the
protection of semiconductor devices
IEC 60269-5, Low-voltage fuses – Part 5: Guidance for the application of low-voltage fuses
IEC 60269-6, Low-voltage fuses – Part 6: Supplementary requirements for fuse-links for the
protection of solar photovoltaic energy systems
IEC 60364-3:1993, Electrical installations of buildings – Part 3: Assessment of general
characteristics
IEC 60364-5-52:2001, Electrical installations of buildings – Part 5-52: Selection and erection of
electrical equipment – Wiring system
IEC 60529:1989, Degrees of protection provided by enclosures (IP Code)
IEC 60584-1:19952013, Thermocouples – Part 1: Reference tables EMF specifications and
tolerances
IEC 60617, Graphical symbols for diagrams
IEC 60664-1:2002, Insulation coordination for equipment within low-voltage supply systems –
Part 1: Principles, requirements and tests
IEC 60695-2-10, Fire hazard testing – Part 2-10: Glowing/hot-wire based test methods – Glow-
wire apparatus and common test procedur
...
IEC 60269-1 ®
Edition 5.0 2024-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Low-voltage fuses –
Part 1: General requirements
Fusibles basse tension –
Partie 1: Exigences générales
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.
Droits de reproduction réservés. Sauf indication contraire, aucune partie de cette publication ne peut être reproduite ni
utilisée sous quelque forme que ce soit et par aucun procédé, électronique ou mécanique, y compris la photocopie et
les microfilms, sans l'accord écrit de l'IEC ou du Comité national de l'IEC du pays du demandeur. Si vous avez des
questions sur le copyright de l'IEC ou si vous désirez obtenir des droits supplémentaires sur cette publication, utilisez
les coordonnées ci-après ou contactez le Comité national de l'IEC de votre pays de résidence.
IEC Secretariat Tel.: +41 22 919 02 11
3, rue de Varembé info@iec.ch
CH-1211 Geneva 20 www.iec.ch
Switzerland
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 IEC Products & Services Portal - products.iec.ch
The advanced search enables to find IEC publications by a Discover our powerful search engine and read freely all the
variety of criteria (reference number, text, technical publications previews, graphical symbols and the glossary.
committee, …). It also gives information on projects, replaced With a subscription you will always have access to up to date
and withdrawn publications. content tailored to your needs.
IEC Just Published - webstore.iec.ch/justpublished
Electropedia - www.electropedia.org
Stay up to date on all new IEC publications. Just Published
The world's leading online dictionary on electrotechnology,
details all new publications released. Available online and once
containing more than 22 500 terminological entries in English
a month by email.
and French, with equivalent terms in 25 additional languages.
Also known as the International Electrotechnical Vocabulary
IEC Customer Service Centre - webstore.iec.ch/csc
(IEV) online.
If you wish to give us your feedback on this publication or need
further assistance, please contact the Customer Service
Centre: sales@iec.ch.
A propos de l'IEC
La Commission Electrotechnique Internationale (IEC) est la première organisation mondiale qui élabore et publie des
Normes internationales pour tout ce qui a trait à l'électricité, à l'électronique et aux technologies apparentées.
A propos des publications IEC
Le contenu technique des publications IEC est constamment revu. Veuillez vous assurer que vous possédez l’édition la
plus récente, un corrigendum ou amendement peut avoir été publié.
Recherche de publications IEC - Découvrez notre puissant moteur de recherche et consultez
webstore.iec.ch/advsearchform gratuitement tous les aperçus des publications, symboles
La recherche avancée permet de trouver des publications IEC graphiques et le glossaire. Avec un abonnement, vous aurez
en utilisant différents critères (numéro de référence, texte, toujours accès à un contenu à jour adapté à vos besoins.
comité d’études, …). Elle donne aussi des informations sur les
projets et les publications remplacées ou retirées. Electropedia - www.electropedia.org
Le premier dictionnaire d'électrotechnologie en ligne au monde,
IEC Just Published - webstore.iec.ch/justpublished
avec plus de 22 500 articles terminologiques en anglais et en
Restez informé sur les nouvelles publications IEC. Just
français, ainsi que les termes équivalents dans 25 langues
Published détaille les nouvelles publications parues.
additionnelles. Egalement appelé Vocabulaire
Disponible en ligne et une fois par mois par email.
Electrotechnique International (IEV) en ligne.
Service Clients - webstore.iec.ch/csc
Si vous désirez nous donner des commentaires sur cette
publication ou si vous avez des questions contactez-nous:
sales@iec.ch.
IEC Products & Services Portal - products.iec.ch
IEC 60269-1 ®
Edition 5.0 2024-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Low-voltage fuses –
Part 1: General requirements
Fusibles basse tension –
Partie 1: Exigences générales
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.120.50 ISBN 978-2-8322-9108-5
– 2 – IEC 60269-1:2024 © IEC 2024
CONTENTS
FOREWORD . 7
1 Scope . 9
2 Normative references . 9
3 Terms and definitions . 10
3.1 Fuses and their component parts . 10
3.2 General terms . 12
3.3 Characteristic quantities . 14
4 Conditions for operation in service . 17
4.1 General . 17
4.2 Ambient air temperature (T ) . 18
a
4.3 Altitude . 18
4.4 Atmospheric conditions . 18
4.5 Voltage . 18
4.6 Current . 18
4.7 Frequency, power factor and time constant . 18
4.7.1 Frequency . 18
4.7.2 Power factor . 19
4.7.3 Time constant (τ) . 19
4.8 Conditions of installation . 19
4.9 Utilization class . 19
4.10 Selectivity of fuse-links . 19
5 Classification . 19
6 Characteristics of fuses . 19
6.1 Summary of characteristics . 19
6.1.1 General . 19
6.1.2 Fuse-holders . 19
6.1.3 Fuse-links . 20
6.1.4 Complete fuses . 20
6.2 Rated voltage . 20
6.3 Rated current . 21
6.3.1 Rated current of the fuse-link . 21
6.3.2 Rated current of the fuse-holder . 21
6.4 Rated frequency (see 7.1 and 7.2) . 21
6.5 Rated power dissipation of a fuse-link and rated acceptable power
dissipation of a fuse-holder. . 21
6.6 Limits of time-current characteristics . 21
6.6.1 General . 21
6.6.2 Time-current characteristics, time-current zones . 21
6.6.3 Conventional times and currents . 22
6.6.4 Gates . 22
6.7 Breaking range and breaking capacity . 23
6.7.1 Breaking range and utilization category . 23
6.7.2 Rated breaking capacity . 24
6.8 Cut-off current and I t characteristics . 24
6.8.1 General . 24
6.8.2 Cut-off current characteristics . 24
6.8.3 I t characteristics . 24
7 Markings. 24
7.1 General . 24
7.2 Markings of fuse-holders . 25
7.3 Markings of fuse-links . 25
8 Standard conditions for construction . 25
8.1 Mechanical design . 25
8.1.1 Replacement of fuse-links . 25
8.1.2 Connections, including terminals . 25
8.1.3 Fuse-contacts . 26
8.1.4 Construction of a gauge-piece . 26
8.1.5 Mechanical strength of the fuse-link . 26
8.2 Insulating properties and suitability for isolation . 26
8.3 Temperature rise, power dissipation of the fuse-link and acceptable power
dissipation of a fuse-holder . 27
8.4 Operation . 27
8.5 Breaking capacity . 28
8.6 Cut-off current characteristic . 28
8.7 I t characteristics . 29
8.8 Overcurrent selectivity of fuse-links . 29
8.9 Protection against electric shock . 30
8.9.1 General . 30
8.9.2 Clearances and creepage distances . 30
8.9.3 Leakage currents of fuses suitable for isolation . 31
8.9.4 Additional constructional requirements for fuse holders for linked fuse-
carriers, suitable for isolation . 31
8.10 Resistance to heat . 32
8.11 Mechanical strength . 32
8.12 Resistance to corrosion . 32
8.12.1 General . 32
8.12.2 Resistance to rusting . 32
8.12.3 Resistance to season cracking . 32
8.13 Resistance to abnormal heat and fire . 32
8.14 Electromagnetic compatibility . 32
9 Tests . 32
9.1 Overview. 32
9.1.1 General . 32
9.1.2 Kind of tests . 33
9.1.3 Ambient air temperature (T ) . 33
a
9.1.4 Condition of the fuse . 33
9.1.5 Arrangement of the fuse and dimensions . 33
9.1.6 Testing of fuse-links . 33
9.1.7 Testing of fuse-holders . 37
9.2 Verification of the insulating properties and of the suitability for isolation . 38
9.2.1 Arrangement of the fuse-holder . 38
9.2.2 Verification of the insulating properties . 38
9.2.3 Verification of the suitability for isolation . 39
9.2.4 Acceptability of test results . 40
– 4 – IEC 60269-1:2024 © IEC 2024
9.3 Verification of temperature rise and power dissipation . 40
9.3.1 Arrangement of the fuse . 40
9.3.2 Measurement of the temperature rise . 41
9.3.3 Measurement of the power dissipation of the fuse-link . 41
9.3.4 Test method . 41
9.3.5 Acceptability of test results . 43
9.4 Verification of operation . 43
9.4.1 Arrangement of the fuse . 43
9.4.2 Ambient air temperature . 43
9.4.3 Test method and acceptability of test results . 43
9.5 Verification of the breaking capacity . 47
9.5.1 Arrangement of the fuse . 47
9.5.2 Characteristics of the test circuit . 47
9.5.3 Measuring instruments. 48
9.5.4 Calibration of test circuit . 48
9.5.5 Test method . 50
9.5.6 Ambient air temperature . 52
9.5.7 Interpretation of oscillograms . 52
9.5.8 Acceptability of test results . 52
9.6 Verification of the cut-off current characteristics . 53
9.6.1 Test method . 53
9.6.2 Acceptability of test results . 53
9.7 Verification of I t characteristics and overcurrent selectivity . 53
9.7.1 Test method . 53
9.7.2 Acceptability of test results . 53
9.7.3 Verification of compliance for fuse-links at 0,01 s . 53
9.7.4 Verification of overcurrent selectivity . 54
9.8 Verification of the degree of protection of enclosures . 54
9.9 Verification of resistance to heat . 54
9.10 Verification of non-deterioration of contacts . 54
9.10.1 General . 54
9.10.2 Arrangement of the fuse . 54
9.10.3 Test method . 54
9.10.4 Acceptability of test results . 54
9.11 Mechanical and miscellaneous tests . 55
9.11.1 Mechanical strength. 55
9.11.2 Miscellaneous tests . 55
9.12 Test of durability of markings . 58
Annex A (informative) Measurement of short-circuit power factor . 68
Annex B (informative) Calculation of pre-arcing I t values for "gG", "gM" and "gU"
fuse‑links and calculation of operating I t values at reduced voltage . 71
B.1 Evaluation of the pre-arcing I t value at 0,01 s . 71
B.2 Calculation of the value of pre-arcing I t under the conditions of test no. 2 . 71
B.3 Calculation of the value of operating I t at reduced voltage . 71
Annex C (informative) Calculation of cut-off current-time characteristic . 72
C.1 Overview. 72
C.2 Preliminary note . 72
C.3 Definition . 72
C.4 Characteristic. 72
C.5 Test condition . 73
C.6 Calculation from the measured values . 73
Annex D (informative) Effect of change of ambient temperature and surroundings on
the performance of fuse-links . 76
D.1 Effect of increase of ambient temperature . 76
D.1.1 On current rating . 76
D.1.2 On temperature rise . 76
D.1.3 On conventional fusing and non-fusing current (I and I ) . 76
f nf
D.1.4 For motor starting conditions . 76
D.2 Effect of decrease of ambient air temperature . 76
D.3 Effect of installation conditions. 76
Annex E (normative) Particular requirements for fuse-bases with screwless-type
terminals for external copper conductors. 77
E.1 General . 77
E.3 Terms and definitions . 77
E.7 Marking . 78
E.8 Standard conditions for construction . 78
E.8.1 Fixed connections including terminals . 78
E.8.2 Dimensions of connectable conductors . 78
E.8.3 Connectable cross-sectional areas . 79
E.8.4 Insertion and disconnecting of conductors . 79
E.8.5 Design and construction of terminals . 79
E.8.6 Resistance to ageing . 80
E.9 Tests . 80
E.9.1 Test of reliability of terminals . 80
E.9.2 Tests of reliability of terminals for external conductors: mechanical
strength . 80
E.9.3 Cycling test. 81
Bibliography . 84
Figure 1 – Diagram illustrating the means of verification of the time-current
characteristic, using the results of the tests at the "gate" currents (example) . 59
Figure 2 – Overload curve and time-current characteristic for "a" fuse-links . 60
Figure 3 – Time-current zone for aM fuses . 61
Figure 4 – General presentation of the cut-off characteristics for a series of AC
fuse‑links . 62
Figure 5 – Typical diagram of the circuit used for breaking capacity test (see 9.5) . 63
Figure 6 – Interpretation of oscillograms taken during the AC breaking-capacity tests
(see 9.5.7) . 64
Figure 7 – Interpretation of oscillograms taken during the DC breaking-capacity tests
(see 9.5.7) . 65
Figure 8 – Glow-wire and position of the thermocouple . 66
Figure 9 – Test apparatus (example) . 67
Figure A.1 – Determination of circuit-impedance for calculation of power factor in
accordance with method I . 70
Figure C.1 – Cut-off current characteristic as a function of actual pre-arcing time . 75
Figure E.1 – Connecting samples . 82
– 6 – IEC 60269-1:2024 © IEC 2024
Figure E.2 – Examples of terminals . 83
Table 1 – Standard values of AC rated voltages for fuses . 20
Table 2 – Preferred values of DC rated voltages for fuses . 20
Table 3 – Conventional time and current for "gG", and "gM" fuse-links . 22
a
Table 4 – Gates for specified pre-arcing times of "gG" and "gM" fuse-links . 23
Table 5 – Gates for "aM ' fuse-links (all rated currents) . 23
Table 6 – Temperature rise limits ∆T = (T – T ) for terminals . 27
a
Table 7 – Maximum arc voltage . 28
Table 8 – Pre-arcing I t values at 0,01 s for "gG" and "gM" fuse-links . 29
Table 9 – Rated impulse withstand voltage . 30
Table 10 – Minimum clearances in air . 30
Table 11 – Minimum creepage distances . 31
Table 12 – Survey of complete tests on fuse-links and number of fuse-links to be
tested . 35
Table 13 – Survey of tests on fuse-links of smallest rated current of homogeneous
series and number of fuse-links to be tested . 36
Table 14 – Survey of tests on fuse-links of rated currents between the largest and the
smallest rated current of a homogeneous series and number of fuse-links to be tested . 37
Table 15 – Survey of complete tests on fuse-holders and number of fuse-holders to be
tested . 37
Table 16 – Test voltage . 39
Table 17 – Test voltage across the poles for the verification of the suitability for
isolation . 40
Table 18 – Cross-sectional area of copper conductors for tests corresponding to
Subclauses 9.3 and 9.4. 42
Table 19 – Cross-section areas of the copper conductors for the test of "aM" fuses . 45
Table 20 – Table for test in Subclause 9.4.3.5 . 46
Table 21 – Values for breaking-capacity tests on AC fuses . 49
Table 22 – Values for breaking-capacity tests on DC fuses . 50
Table E.1 – Connectable conductors . 79
Table E.2 – Cross-sections of copper conductors connectable to terminals . 79
Table E.3 – Pull forces . 81
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
LOW-VOLTAGE FUSES –
Part 1: General requirements
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) IEC draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). IEC takes no position concerning the evidence, validity or applicability of any claimed patent rights in
respect thereof. As of the date of publication of this document, IEC had not received notice of (a) patent(s), which
may be required to implement this document. However, implementers are cautioned that this may not represent
the latest information, which may be obtained from the patent database available at https://patents.iec.ch. IEC
shall not be held responsible for identifying any or all such patent rights.
IEC 60269-1 has been prepared by subcommittee 32B: Low-voltage fuses, of IEC technical
committee 32: Fuses. It is an International Standard.
This fifth edition cancels and replaces the fourth edition published in 2006, Amendment 1:2009
and Amendment 2:2014. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) New numbering, editorial corrections and normative references updated;
b) Term "discrimination" replaced by "selectivity" and "utilization category" by "utilization
class";
c) Term "fuses for authorized and unskilled persons" updated;
d) Replacement of fuse-link added;
– 8 – IEC 60269-1:2024 © IEC 2024
e) Standard values for AC and DC voltages updated;
f) Rated currents 425A, 355A, and 1 600A added;
g) Marking: requirements and tests separated to the relevant subclauses;
h) Requirements for temperature rise limited to terminal temperature rise only;
i) Graphic symbol for fuse-base updated,
The text of this International Standard is based on the following documents:
Draft Report on voting
32B/748/FDIS 32B/756/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.
IEC 60269 consists of the following parts, under the general title Low-voltage fuses:
Part 1: General requirements
Part 2: Supplementary requirements for fuses for use by authorized persons (fuses mainly
for industrial application) – Examples of standardized systems of fuses A to I
Part 3: Supplementary requirements for fuses for use by unskilled persons (fuses mainly for
household or similar application) – Examples of standardized systems of fuses A to
F
Part 4: Supplementary requirements for fuse-links for the protection of semiconductor
devices
Part 5: Guidance for the application of low-voltage fuses
Part 6: Supplementary requirements for fuse-links for the protection of solar photovoltaic
energy systems
Part 7: Battery Fuses
For reasons of convenience, when a part of this publication has come from other publications,
a remark to this effect has been inserted in the text.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn, or
• revised.
LOW-VOLTAGE FUSES –
Part 1: General requirements
1 Scope
This part of IEC 60269 is applicable to fuses incorporating enclosed current-limiting fuse-links
with rated breaking capacities of not less than 6 kA, intended for protecting power-frequency
AC circuits of nominal voltages not exceeding 1 000 V or DC circuits of nominal voltages not
exceeding 1 500 V.
Subsequent parts of this standard, referred to herein, cover supplementary requirements for
such fuses intended for specific conditions of use or applications.
Fuse-links intended to be included in fuse-switch combinations according to IEC 60947-3
should also comply with the following requirements.
As far as not stated in subsequent parts for fuse-links, details of performance (see 3.2.4) on
DC circuits should be stated in the manufacturer's literature.
NOTE 1 Modifications of, and supplements to, this document required for certain types of fuses for particular
applications – for example, certain fuses for rolling stock, or fuses for high-frequency circuits – will be covered, if
necessary, by separate standards.
NOTE 2 This document does not apply to miniature fuses, these being covered by IEC 60127.
The object of this standard series is to establish the characteristics of fuses or parts of fuses
(fuse-base, fuse-carrier, fuse-link) in such a way that they can be replaced by other fuses or
parts of fuses having the same characteristics provided that they are interchangeable as far as
their dimensions are concerned. For this purpose, this standard series refers in particular to
– the following characteristics of fuses:
• rated values;
• insulation;
• temperature rise in normal service;
• power dissipation and acceptable power dissipation;
• time/current characteristics;
• breaking capacity;
• cut-off current characteristics and their I t characteristics.
– type test for verification of the characteristics of fuses;
– the marking of fuses.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements 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 60269-2, Low-voltage fuses – Part 2: Supplementary requirements for fuses for use by
authorized persons (fuses mainly for industrial application) – Examples of standardized systems
of fuses A to K
– 10 – IEC 60269-1:2024 © IEC 2024
IEC 60529, Degrees of protection provided by enclosures (IP Code)
IEC 60584-1:2013, Thermocouples – Part 1: EMF specifications and tolerances
IEC 60617, Graphical symbols for diagrams
IEC 60664-1:2002, Insulation coordination for equipment within low-voltage supply systems –
Part 1: Principles, requirements and tests
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
NOTE For general definitions concerning fuses, see also IEC 60050-441.
3.1 Fuses and their component parts
3.1.1
fuse
device that by the fusing of one or more of its specially designed and proportioned components
opens the circuit in which it is inserted by breaking the current when this exceeds a given value
for a sufficient time. The fuse comprises all the parts that form the complete device
[SOURCE: IEC 60050-441:1984, 441-18-01]
3.1.2
fuse-holder
combination of the fuse-base with its fuse-carrier
Note 1 to entry: Where, in this document, the term "fuse-holder" is used, it covers fuse-bases and/or fuse-carriers,
if no clearer distinction is necessary.
[SOURCE: IEC 60050-441:1984, 441-18-14]
3.1.2.1
fuse-base (fuse-mount)
fixed part of a fuse provided with contacts and terminals
Note 1 to entry: Where applicable, covers are considered as part of the fuse-base.
[SOURCE: IEC 60050-441:1984, 441-18-02]
3.1.2.2
fuse-carrier
movable part of a fuse designed to carry a fuse-link
[SOURCE: IEC 60050-441:1984, 441-18-13]
3.1.3
fuse-link
part of a fuse including the fuse-element(s), intended to be replaced after the fuse has operated
[SOURCE: IEC 60050-441:1984, 441-18-09]
3.1.4
fuse-contact
two or more conductive parts designed to ensure circuit continuity between a fuse-link and the
corresponding fuse-holder
3.1.5
fuse-element
part of the fuse-link designed to melt under the action of current exceeding some definite value
for a definite period of time
Note 1 to entry: The fuse-link may comprise several fuse-elements in parallel.
[SOURCE: IEC 60050-441:1984, 441-18-08]
3.1.6
indicating device (indicator)
part of a fuse provided to indicate whether the fuse has operated
[SOURCE: IEC 60050-441:1984, 441-18-17]
3.1.7
striker
mechanical device forming part of a fuse-link which, when the fuse operates, releases the
energy required to cause operation of other apparatus or indicators or to provide interlocking
[SOURCE: IEC 60050-441:1984, 441-18-18]
3.1.8
terminal
conductive part of a fuse provided for electric connection to external circuits
Note 1 to entry: Terminals may be distinguished according to the kind of circuits for which they are intended (for
example, main terminal, earth terminal, etc.) and also according to their design (for example, screw terminal, plug
terminal, etc.).
3.1.9
dummy fuse-link
test fuse-link with defined power dissipation and dimensions
3.1.10
test rig
defined test fuse-base
3.1.11
gauge-piece
additional part of a fuse-base intended to achieve a degree of non-interchangeability
3.1.12
linked fuse-carrier
fuse-carrier which is mechanically linked to
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.
Loading comments...