EN IEC 60269-4:2025
(Main)Low-voltage fuses - Part 4: Supplementary requirements for fuse-links for the protection of semiconductor devices
Low-voltage fuses - Part 4: Supplementary requirements for fuse-links for the protection of semiconductor devices
These supplementary requirements apply to fuse-links for application in equipment containing semiconductor devices for circuits of nominal voltages up to 1 000 V AC. or 1 500 V DC. and also, in so far as they are applicable, for circuits of higher nominal voltages. NOTE 1 Such fuse-Iinks are commonly referred to as "semiconductor fuse-links". NOTE 2 In most cases, a part of the associated equipment serves the purpose of a fuse-base. Owing to the great variety of equipment, no general rules can be given; the suitability of the associated equipment to serve as a fuse- base should be subject to agreement between the manufacturer and the user. However, if separate fuse-bases or fuse-holders are used, they should comply with the appropriate requirements of IEC 60269-1. NOTE 3 IEC 60269-6 (Low-voltage fuses – Part 6: Supplementary requirements for fuse-links for the protection of solar photovoltaic energy systems) is dedicated to the protection of solar photovoltaic energy systems. NOTE 4 These fuse-links are intended for use on systems employing the standardized voltages and tolerances of IEC 60038. Tests carried out on fuse-links in accordance with previous editions of this standard shall remain valid until such time as complimentary equipment has evolved to the standardized voltages and tolerances of IEC 60038. The object of these supplementary requirements is to establish the characteristics of semiconductor fuse-links in such a way that they can be replaced by other fuse-links having the same characteristics, provided that their dimensions are identical. For this purpose, this standard refers in particular to a) the following characteristics of fuses: 1) their rated values; 2) their temperature rises in normal service; 3) their power dissipation; 4) their time-current characteristics; 5) their breaking capacity; 6) their cut-off current characteristics and their I2t characteristics; 7) their arc voltage characteristics; b) type tests for verification of the characteristics of fuses; c) the markings on fuses; d) availability and presentation of technical data (see Annex BB).
Niederspannungssicherungen - Teil 4: Zusätzliche Anforderungen an Sicherungseinsätze zum Schutz von Halbleiter-Bauelementen
Fusibles basse tension - Partie 4: Exigences supplémentaires concernant les éléments de remplacement utilisés pour la protection des dispositifs à semiconducteurs
L'IEC 60269-4:2024 s'applique avec les exigences supplémentaires suivantes. Sauf indication contraire dans le texte qui suit, les éléments de remplacement utilisés pour la protection des dispositifs à semiconducteurs doivent satisfaire à l'ensemble des exigences de l'IEC 60269-1 ainsi qu'aux exigences supplémentaires ci-après. Les présentes exigences supplémentaires s'appliquent aux éléments de remplacement destinés à être associés à des matériels comportant des dispositifs à semiconducteurs et utilisés dans des circuits de tensions nominales inférieures ou égales à 1 000 V en courant alternatif ou à 1 500 V en courant continu. Pour certains éléments de remplacement, des tensions assignées supérieures peuvent être utilisées.
Nizkonapetostne varovalke - 4. del: Dodatne zahteve za taljive vložke za zaščito polprevodniških naprav
Standard IEC 60269-1 se uporablja z naslednjimi dodatnimi zahtevami.
Taljivi vložki za zaščito polprevodniških naprav morajo izpolnjevati vse zahteve standarda IEC 60269-1, razen če je v nadaljevanju navedeno drugače, ter tudi spodaj določene dodatne zahteve.
Te dodatne zahteve veljajo za taljive vložke za uporabo v opremi, ki vsebuje polprevodniške naprave za vezja z nazivnimi napetostmi do 1000 V AC oziroma 1500 V DC. Za nekatere taljive vložke je mogoče uporabiti večje nazivne napetosti.
OPOMBA: Tovrstni taljivi vložki se običajno imenujejo »polprevodniški taljivi vložki«.
Cilj teh dodatnih zahtev je določiti lastnosti polprevodniških taljivih vložkov na način, da jih je mogoče zamenjati z drugimi taljivimi vložki, ki imajo enake lastnosti, pod pogojem, da so njihove mere enake. Za ta namen se ta standard navezuje predvsem na:
a) naslednje lastnosti varovalk:
1) njihove nazivne vrednosti;
2) njihovo povečanje temperature pri normalnem delovanju;
3) njihova izguba moči;
4) njihove časovno-tokovne lastnosti;
5) njihova zmogljivost prekinitve;
6) njihove vrednosti omejitve toka in njihove lastnosti I2t;
7) njihove vrednosti obločne napetosti;
b) tipsko preskušanje za preverjanje lastnosti varovalk;
c) oznake na varovalkah;
d) razpoložljivost in predstavitev tehničnih podatkov (glej dodatek BB).
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
01-oktober-2025
Nizkonapetostne varovalke - 4. del: Dodatne zahteve za taljive vložke za zaščito
polprevodniških naprav
Low-voltage fuses - Part 4: Supplementary requirements for fuse-links for the protection
of semiconductor devices
Niederspannungssicherungen - Teil 4: Zusätzliche Anforderungen an
Sicherungseinsätze zum Schutz von Halbleiter-Bauelementen
Fusibles basse tension - Partie 4: Exigences supplémentaires concernant les éléments
de remplacement utilisés pour la protection des dispositifs à semiconducteurs
Ta slovenski standard je istoveten z: EN IEC 60269-4:2025
ICS:
29.120.50 Varovalke in druga Fuses and other overcurrent
nadtokovna zaščita protection devices
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
EUROPEAN STANDARD EN IEC 60269-4
NORME EUROPÉENNE
EUROPÄISCHE NORM June 2025
ICS 29.120.50 Supersedes EN 60269-4:2009; EN 60269-
4:2009/A1:2012; EN 60269-4:2009/A2:2016
English Version
Low-voltage fuses - Part 4: Supplementary requirements for
fuse-links for the protection of semiconductor devices
(IEC 60269-4:2024)
Fusibles basse tension - Partie 4: Exigences Niederspannungssicherungen - Teil 4: Zusätzliche
supplémentaires concernant les éléments de remplacement Anforderungen an Sicherungseinsätze zum Schutz von
utilisés pour la protection des dispositifs à semiconducteurs Halbleiter-Bauelementen
(IEC 60269-4:2024) (IEC 60269-4:2024)
This European Standard was approved by CENELEC on 2024-10-16. CENELEC members are bound to comply with the CEN/CENELEC
Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.
Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC
Management Centre or to any CENELEC member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the
same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the
Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Türkiye and the United Kingdom.
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2025 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN IEC 60269-4:2025 E
European foreword
The text of document 32B/746/FDIS, future edition 6 of IEC 60269-4, prepared by SC 32B "Low-
voltage fuses" of IEC/TC 32 "Fuses" was submitted to the IEC-CENELEC parallel vote and approved
by CENELEC as EN IEC 60269-4:2025.
The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2026-06-30
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2028-06-30
document have to be withdrawn
This document supersedes EN 60269-4:2009 and all of its amendments and corrigenda (if any).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights.
This document has been prepared under a standardization request addressed to CENELEC by the
European Commission. The Standing Committee of the EFTA States subsequently approves these
requests for its Member States.
Any feedback and questions on this document should be directed to the users’ national committee. A
complete listing of these bodies can be found on the CENELEC website.
Endorsement notice
The text of the International Standard IEC 60269-4:2024 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following notes have to be added for the standard indicated:
IEC 60269-6:2010 NOTE Approved as EN 60269-6:2011 (not modified)
IEC 60269-6:2010/A1:2021 NOTE Approved as EN 60269-6:2011/A1:2023 (not modified)
IEC 60269-7:2021 NOTE Approved as EN IEC 60269-7:2024 (not modified)
IEC 60664-1:2020 NOTE Approved as EN IEC 60664-1:2020 (not modified)
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
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.
NOTE 1 Where an International Publication has been modified by common modifications, indicated by (mod),
the relevant EN/HD applies.
NOTE 2 Up-to-date information on the latest versions of the European Standards listed in this annex is available
here: www.cencenelec.eu.
Publication Year Title EN/HD Year
IEC 60269-1 2024 Low-voltage fuses - Part 1: General EN IEC 60269-1 2025
requirements
IEC 60269-2 (mod) 2013 Low-voltage fuses - Part 2: Supplementary HD 60269-2 2013
requirements for fuses for use by authorized
persons (fuses mainly for industrial
application) - Examples of standardized
systems of fuses A to K
+ A1 2016 + A1 2022
+ A2 2024 + A2 2024
IEC/TR 60269-5 2014 Low-voltage fuses - Part 5: Guidance for the - -
application of low-voltage fuses
+ A1 2020 - -
IEC 60417 - Graphical symbols for use on equipment. - -
Index, survey and compilation of the single
sheets.
ISO 3 - Preferred numbers - Series of preferred - -
numbers
IEC 60269-4 ®
Edition 6.0 2024-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Low-voltage fuses –
Part 4: Supplementary requirements for fuse-links for the protection of
semiconductor devices
Fusibles basse tension –
Partie 4: Exigences supplémentaires concernant les éléments de remplacement
utilisés pour la protection des dispositifs à semiconducteurs
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.120.50 ISBN 978-2-8322-8933-4
– 2 – IEC 60269-4:2024 © IEC 2024
CONTENTS
FOREWORD . 4
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 7
4 Conditions for operation in service . 8
5 Classification . 9
6 Characteristics of fuses . 9
7 Markings. 13
8 Standard conditions for construction . 14
9 Tests . 14
Annex AA (informative) Guidance for the coordination of fuse-links with semiconductor
devices . 26
Annex BB (normative) Survey on information to be supplied by the manufacturer in his
literature (catalogue) or on request for a fuse designed for the protection of
semiconductor devices. 27
Annex CC (normative) Examples of standardized fuse-links for the protection of
semiconductor devices. 28
Bibliography . 45
Figure 101 – Example of a conventional test arrangement for bolted fuse-links . 24
Figure 102 – Example of a conventional test arrangement for blade contact fuse-links . 25
Figure CC.1 – Single body fuse-links . 29
Figure CC.2 – Double body fuse-links . 30
Figure CC.3 – Twin body fuse-links . 31
Figure CC.4 – Striker fuse-links . 31
Figure CC.5 – Fuse-links with bolted connections, type B, body sizes 000 and 00 . 33
Figure CC.6 – Fuse-links with bolted connections, type B, body sizes 0, 1, 2 and 3 . 34
Figure CC.7 – Bolted fuse-links, type C . 36
Figure CC.8 – Flush end fuse-links, type A . 38
Figure CC.9 – Flush end fuse-links, type B . 40
Figure CC.10 – Fuse-links with cylindrical contact caps, type A . 41
Figure CC.11 – Fuse-links with cylindrical contact caps, type B . 43
Figure CC.12 – Fuse-links with cylindrical contact caps with striker, type B (additional
dimensions for all sizes except 10 × 38) . 44
Table 101 – Conventional time and current for "gR" and "gS" fuse-links . 11
Table 102 – List of complete tests . 15
Table 103 – Survey of tests on fuse-links of the smallest rated current of a
homogeneous series . 16
Table 107 – Cross-sectional area of copper conductors for high current ratings tests . 17
Table 104 – Values for breaking-capacity tests on AC fuses . 20
Table 105 – Values for breaking-capacity tests on DC fuses . 21
Table 106 – Values for breaking-capacity tests on VSI fuse-links . 21
IEC 60269-4:2024 © IEC 2024 – 3 –
Table CC.1 – Typical rated voltages and preferred maximum rated currents . 42
– 4 – IEC 60269-4:2024 © IEC 2024
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
LOW-VOLTAGE FUSES –
Part 4: Supplementary requirements for fuse-links
for the protection of semiconductor devices
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 60269-4 has been prepared by subcommittee 32B: Low-voltage fuses, of IEC technical
committee 32: Fuses. It is an International Standard.
This sixth edition cancels and replaces the fifth edition published in 2009, Amendment 1:2012
and Amendment 2:2016. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) the introduction of voltage source inverter fuse-links, including test requirements.
b) coverage of the tests on operating characteristics for AC. by the breaking capacity tests.
c) the updating of examples of standardised fuse-links for the protection of semiconductor
devices.
IEC 60269-4:2024 © IEC 2024 – 5 –
The text of this International Standard is based on the following documents:
Draft Report on voting
32B/746/FDIS 32B/753/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.
This part is to be used in conjunction with IEC 60269-1:2024, Low-voltage fuses – Part 1:
General requirements.
This Part 4 supplements or modifies the corresponding clauses or subclauses of Part 1.
Where no change is necessary, this Part 4 indicates that the relevant clause or subclause
applies.
Tables and figures which are additional to those in Part 1 are numbered starting from 101.
Additional annexes are lettered AA, BB, etc.
A list of all parts of the IEC 60269 series, under the general title: Low-voltage fuses, can be
found on the IEC website.
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.
– 6 – IEC 60269-4:2024 © IEC 2024
LOW-VOLTAGE FUSES –
Part 4: Supplementary requirements for fuse-links
for the protection of semiconductor devices
1 Scope
IEC 60269-1 applies with the following supplementary requirements.
Fuse-links for the protection of semiconductor devices shall comply with aIl requirements of
IEC 60269-1, if not otherwise indicated hereinafter, and shall also comply with the
supplementary requirements laid down below.
These supplementary requirements apply to fuse-links for application in equipment containing
semiconductor devices for circuits of nominal voltages up to 1 000 V AC or 1 500 V DC. For
some fuse-links higher rated voltages can be used.
NOTE Such fuse-Iinks are commonly referred to as "semiconductor fuse-links".
The object of these supplementary requirements is to establish the characteristics of
semiconductor fuse-links in such a way that they can be replaced by other fuse-links having the
same characteristics, provided that their dimensions are identical. For this purpose, this
standard refers in particular to
a) the following characteristics of fuses:
1) their rated values
2) their temperature rises in normal service
3) their power dissipation
4) their time-current characteristics
5) their breaking capacity
6) their cut-off current characteristics and their I t characteristics
7) their arc voltage characteristics
b) type tests for verification of the characteristics of fuses
c) the markings on fuses
d) availability and presentation of technical data (see Annex BB).
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 60269-1:2024, Low-voltage fuses – Part 1: General requirements
IEC 60269-2:2013, 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
IEC 60269-2:2013/AMD1:2016
IEC 60269-2:2013/AMD2:2024
IEC 60269-4:2024 © IEC 2024 – 7 –
IEC TR 60269-5:2014, Low-voltage fuses – Part 5: Guidance for the application of low-voltage
fuses
IEC TR 60269-5:2014/AMD1:2020
IEC 60417, Graphical symbols for use on equipment
ISO 3, Preferred numbers – Series of preferred numbers
3 Terms and definitions
IEC 60269-1 applies with the following supplementary definitions.
3.2 General terms
3.2.101
semiconductor device
device whose essential characteristics are due to the flow of charge carriers within a
semiconductor.
[SOURCE: IEC 60050-521:2002, 521-04-01]
3.2.102
semiconductor fuse-link
current-limiting fuse-link capable of breaking, under specific conditions, any current value within
the breaking range (see 8.4)
3.2.103
signalling device
device forming part of the fuse and signalling the fuse operation to a remote place
Note 1 to entry: A signalling device consists of a striker and an auxiliary switch. Electronic devices may also be
used.
3.2.104
voltage source inverter
VSI
a voltage stiff inverter
Note 1 to entry: Also referred to as a voltage stiff inverter i.e. an inverter that supplies current without any practical
change in its output voltage.
[SOURCE: IEC 60050-551:1998, 551-12-11]
3.2.105
voltage source inverter fuse-link
VSI fuse-link
current-limiting fuse-link capable of breaking, under specified conditions, the short circuit
current supplied by the discharge of a DC-link capacitor in a voltage source inverter
Note 1 to entry: The abbreviation "VSI fuse-link" is used in this document.
Note 2 to entry: A VSI fuse-link usually operates under a short circuit current supplied by the discharge of a DC-
link capacitor through a very low inductance, in order to allow high frequency in normal operation. This short circuit
condition leads to a very high rate of rise of current equivalent to a very low value of time constant, typically 3 ms or
less. The supply voltage is DC, even though the applied voltage decreases as the current increases during the short
circuit.
Note 3 to entry: In some multiple AC drive applications, individual output inverters may be remote from the main
input rectifier. In these cases, the associated fault circuit impedances may influence the operation of the fuse-links.
– the associated time constant and the size of the capacitors need to be considered when choosing the appropriate
short circuit protection.
– 8 – IEC 60269-4:2024 © IEC 2024
4 Conditions for operation in service
IEC 60269-1 applies with the following supplementary requirements.
Fuses must be only used according to their rated values.
4.5 Voltage
4.5.1 Rated voltage
For AC, the rated voltage of a fuse-link is related to the applied voltage; it is based on the RMS
value of a sinusoidal AC voltage. It is further assumed that the applied voltage retains the same
value throughout the operation of the fuse-link. All tests to verify the ratings are based on this
assumption.
For DC and VSI fuse-links, the rated voltage of a fuse-link is related to the applied voltage. It is
based on the mean value. When DC is obtained by rectifying AC, the ripple is assumed not to
cause a variation of more than 5 % above or 9 % below the mean value.
4.5.2 Applied voltage in service
Under service conditions, the applied voltage is that voltage which, in the fault circuit, causes
the current to increase to such proportions that the fuse-link will operate.
For AC, consequently, the value of the applied voltage in a single-phase AC circuit is usually
identical to the power-frequency recovery voltage. For all cases other than the sinusoidal AC
voltage, it is necessary to know the applied voltage as a function of time.
For a unidirectional voltage and for VSI fuse-links, the important values are:
– the average value over the entire period of the operation of the fuse-link;
– the instantaneous value near the end of the arcing period.
4.6 Current
The rated current of a semiconductor fuse-link is based on the RMS value of a sinusoidal AC
current at rated frequency.
For DC, the RMS value of current is assumed not to exceed the RMS value based on a
sinusoidal AC current at rated frequency.
NOTE The thermal response time of the fuse-element may be so short that it cannot be assumed that operation
under conditions which deviate much from sinusoidal current can be estimated on the basis of the RMS current alone.
This is so, in particular at lower frequency values and when the current presents salient peaks separated by
appreciable intervals of insignificant current; for example, in the case of frequency converters and traction
applications.
4.7 Frequency, power factor and time constant
4.7.1 Frequency
The rated frequency refers to the frequency of the sinusoidal current and voltage that form the
basis of the type tests.
4.7.3 Time constant (τ)
For DC, the time constants expected in practice are considered to correspond to those in
Table 105.
IEC 60269-4:2024 © IEC 2024 – 9 –
For VSI fuse-links, equivalent time constants expected in practice are considered to correspond
to those in Table 106.
NOTE 2 The high rate of rise of short circuit current is due to the low inductance, which is considered to be
equivalent to a low time constant.
NOTE 3 Instead of time constant di/dt can be used in case of short circuit condition.
di/dt = E/L.
E = voltage value of the DC power source,
L = total inductance of the capacitor discharge circuit.
5 Classification
IEC 60269-1 applies.
6 Characteristics of fuses
IEC 60269-1 applies with the following supplementary requirements.
6.1 Summary of characteristics
6.1.3 Fuse-links
a) Rated voltage (see 6.2)
b) Rated current (see 6.3 of IEC 60269-1:2024)
c) Kind of current and frequency (see 6.4 of IEC 60269-1:2024)
d) Rated power dissipation (see 6.5 of IEC 60269-1:2024)
e) Time-current characteristics (see 6.6)
f) Breaking range (see 6.7.1 of IEC 60269-1:2024)
g) Rated breaking capacity (see 6.7.2 of IEC 60269-1:2024)
h) Cut-off current characteristics (see 6.8.2)
i) I t characteristics (see 6.8.3)
j) Dimensions or size (if applicable)
k) Arc voltage characteristics (see 6.9)
l) Fuse-links may only be used with the fuse-base and/or fuse-holder assigned by the
manufacturer and defined in the manufacturer’s instructions
6.2 Rated voltage
For rated AC voltages up to 690 V and DC voltages up to 750 V, IEC 60269-1 applies; for higher
voltages, the values shall be selected from the R 5 series or, where not possible, from the R 10
series of ISO 3.
A fuse-link shall have an AC voltage rating or a DC voltage rating or a VSI voltage rating. It may
have one or more of these voltage ratings.
6.4 Rated frequency
The rated frequency is that frequency to which the performance data are related.
– 10 – IEC 60269-4:2024 © IEC 2024
6.5 Rated power dissipation of the fuse-link and rated acceptable power dissipation of
a fuse-holder
In addition to the requirements of IEC 60269-1, the manufacturer shall indicate the power
dissipation as a function of current for the range 50 % to 100 % of the rated current.
In cases where the resistance of the fuse-link is of interest, this resistance should be determined
from the functional relation between the power dissipation and the associated value of current.
6.6 Limits of time-current characteristics
6.6.2 Time-current characteristics, time-current zones
6.6.2.1 General requirements
The time-current characteristics depend on the design of the fuse-link, and, for a given fuse-
link, on the ambient air temperature and the cooling conditions.
The manufacturer shall provide time-current characteristics based on an ambient temperature
of 20 °C to 25 °C in accordance with the conditions specified in 9.3. The time-current
characteristics of interest are the pre-arcing characteristic and operating characteristics.
For AC, the time-current characteristics are stated at rated frequency and for pre-arcing or
operating times longer than 0,1 s.
For DC, they are stated for time constants according to Table 105 and for pre-arcing or
operating times longer than 15τ.
For the higher values of prospective current (shorter times), the same information shall be
presented in the form of I t characteristics (see 6.8.2).
6.6.2.2 Pre-arcing time-current characteristics
For AC, the pre-arcing time-current characteristic shall be based on a symmetrical AC current
of a stated value of frequency (rated frequency).
For DC, the pre-arcing time-current characteristic is of particular significance for times
exceeding 15τ for the relevant circuit, and is identical to the AC pre-arcing time-current
characteristic in this zone.
NOTE 1 Because of the wide range of circuit time constants likely to be experienced in service, the information for
times shorter than 15τ is conveniently expressed as a pre-arcing I t characteristic.
NOTE 2 The value of 15τ has been chosen to avoid the effects which different rates of rise of current have on the
pre-arcing time-current characteristic at shorter times.
6.6.2.3 Operating time-current characteristics
For AC with times longer than 0,1 s and for DC with times longer than 15τ, the arcing period is
negligible compared to the pre-arcing time. The operating time is then equivalent to the pre-
arcing time.
6.6.3 Conventional times and currents
6.6.3.1 Conventional times and currents for "aR" fuse-links
See 8.4. and Table 101
IEC 60269-4:2024 © IEC 2024 – 11 –
6.6.3.2 Conventional times and currents for "gR" and "gS" fuse-links
The conventional times and currents are given in Table 101.
Table 101 – Conventional time and current for "gR" and "gS" fuse-links
Conventional current
Rated current Conventional time
Type "gR" Type "gS"
A h
I I I I
nf f nf f
I ≤ 4 1 1,1 I 2,1 I 1,5 I 2,1 I
n n n n n
4 < I < 16 1 1,1 I 1,9 I 1,5 I 1,9 I
n n n n n
16 ≤ I ≤ 63 1
n
63 < I ≤ 160 2
n
1,1 I 1,6 I 1,25 I 1,6 I
n n n n
160 < I ≤ 400 3
n
400 < I 4
n
NOTE The conventional times also apply for "aR" – fuses
6.6.4 Gates
Not applicable.
6.7 Breaking range and breaking capacity
6.7.1 Breaking range and utilization class
The first letter shall indicate the breaking range:
– "a" fuse-links (partial-range breaking capacity, see 8.4);
– "g" fuse-links (full-range breaking capacity).
The second letter "R" and "S" shall indicate the utilization class for fuse-links complying with
this standard for the protection of semiconductor devices.
The type "R" is typically faster acting than type "S" and gives lower I t values.
The type "S" generally has lower power dissipation and gives enhanced utilization of cables
compared to type "R".
For example:
– aR indicates fuse-links with partial range breaking capacity for the protection of
semiconductor devices;
– gR indicates fuse-links with full-range breaking capacity for general application and
semiconductor protection, optimised to low I t values;
– gS indicates fuse-links with full range breaking capacity for general application and
semiconductor protection, optimised to low power dissipation.
Some aR fuse-links are used to protect voltage source inverters. Even though they are common
aR fuses on AC, they must be tested differently under VSI DC short-circuit conditions. For these
reasons, their designation is still "aR" but their DC characteristics must be clearly stated "for
VSI protection" in the manufacturer’s data sheets.
– 12 – IEC 60269-4:2024 © IEC 2024
6.7.2 Rated breaking capacity
A breaking capacity of at least 50 kA for AC and 20 kA for DC is required.
For AC, the rated breaking capacity is based on type tests performed in a circuit containing only
linear impedance and with a constant sinusoidal applied voltage of rated frequency.
For DC, the rated breaking capacity is based on type tests performed in a circuit containing
only linear inductance and resistance with mean applied voltage.
For VSI, the rated breaking capacity is based on type tests performed in a circuit with low time
constant. The time constant for tests is defined in Table 106. The required rated maximum
breaking capacity of VSI fuses is at least 20 kA.
NOTE The addition in practical applications of non-linear impedances and unidirectional voltage components may
significantly influence the breaking severity either in a favourable or unfavourable direction.
6.8 Cut-off current and I t characteristics
6.8.2 Cut-off current characteristics
The manufacturer shall provide the cut-off current characteristics which shall be given,
according to the example shown in Figure 4 of IEC 60269-1:2024, in a double logarithmic
presentation with the prospective current as abscissa and, if necessary, with applied voltage
and/or frequency as a parameter.
For AC, the cut-off current characteristics shall represent the highest values of current likely to
be experienced in service. They shall refer to the conditions corresponding to the test conditions
of this standard, for example, given voltage, frequency and power-factor values. The cut-off
current characteristics may be defined by the tests specified in 9.6.
For DC, the cut-off current characteristics shall represent the highest values of current likely to
be experienced in service in circuits having a time constant specified in Table 105 for aR, gS
and gR fuse-links, or in Table 106 for aR fuse-links in VSI applications. For aR, gS and gR
fuse-links, these values will be exceeded in circuits of smaller time constants than those of
Table 105. The manufacturer shall provide the relevant information to enable the determination
of these higher cut-off current characteristics.
NOTE The cut-off current characteristic varies with the circuit time constant. The manufacturer should provide the
relevant information to enable these variations to be determined at least for time constants of 5 ms and 10 ms.
6.8.3 I t characteristics
6.8.3.1 Pre-arcing I t characteristic
For AC, the manufacturer shall provide the pre-arcing I t characteristic based on a symmetrical
AC current at a stated frequency value (rated frequency).
For DC, the manufacturer shall provide the pre-arcing I t characteristic based on RMS DC
current at a time constant specified in Table 105 for aR, gS and gR fuse-links or in Table 106
for aR fuse-links in VSI applications.
For DC, the prearcing I t value represents the lowest value likely to be experienced in service.
It shall be based on RMS DC current as defined in the test requirements of test No.1 of the
breaking capacity.
IEC 60269-4:2024 © IEC 2024 – 13 –
6.8.3.2 Operating I t characteristics
For AC, the manufacturer shall provide the operating I t characteristics given with applied
voltage as a parameter and for a stated power-factor value. In principle, they shall be based on
the moment of current initiation that leads to the highest operating I t value (see 9.7). The
voltage parameters shall include at least 100 %, and 50 % of rated voltage.
For DC, the manufacturer shall provide the operating I t characteristics given with the applied
voltage as a parameter and for a time constant specified in the Table 105 for aR, gS and gR
fuse-links, or Table 106 for aR fuse-links in VSI applications. The voltage parameters shall
include at least 100 % and 50 % of rated voltage. It is permitted to determine the operating I t
characteristics at lower voltages from tests in accordance with Table 105 or Table 106
according to their DC. application or VSI application.
The I t at reduced voltages may be calculated using the method described in IEC 60269-1:2024,
Clause B.3.
6.9 Arc voltage characteristics
Arc voltage characteristics provided by the manufacturer shall give the highest (peak) value of
arc voltage as a function of the applied voltage of the circuit in which the fuse-link is inserted
and, in the case of AC, for power factors as stated in Table 104 and, in the case of DC at time
constants specified in Table 105 or in Table 106 according to their DC application or VSI
application.
7 Markings
IEC 60269-1 applies with the following supplementary requirements.
7.3 Marking of fuse-link
Subclause 7.3 of IEC 60269-1:2024 applies with the following addition:
– manufacturer's identification reference and/or symbols enabling all the characteristics listed
in 6.1.3 of IEC 60269-1:2024 to be found;
– utilization class, "aR" or "gR" or "gS";
– a combination of symbols of IEC 60417 of a fuse (5016) and a rectifier (5186) as shown
below:
Symbol IEC 60417-5016 (2002-10) Symbol IEC 60417-5186 (2002-10)
For VSI rated fuse-links an additional mark, e.g. "1 200V DC VSI" with the voltage rating value
must be stated on the product.
– 14 – IEC 60269-4:2024 © IEC 2024
8 Standard conditions for construction
IEC 60269-1 applies with the following supplementary requirements.
8.3 Temperature rise and power dissipation of the fuse-link and acceptable power
dissipation of a fuse-holder
Fuse-links shall be so designed and proportioned as to carry, when tested in accordance with
9.3, the rated current without exceeding,
– the temperature rise limit of the hottest upper metal part of the fuse-link indicated by the
manufacturer instructions (see Figure 101 and Figure 102).
– the power dissipation at the rated current indicated by the manufacturer instructions.
8.4 Operation
The fuse-link shall be so designed and proportioned as to carry continuously any value of
current up to its rated current.
"aR" fuse-links shall operate and break the circuit for any current value not exceeding the rated
breaking capacity and not less than the current I (see Table 104 and Table 105).
2a
For "gR" and "gS" fuse-links within the conventional time and at currents defined in Table 101:
– it shall not operate, when it carries any current not exceeding the conventional non-fusing
current (I );
nf
– it shall operate when it carries any current equal to, or exceeding, the conventional fusing
current (I ) and equal to or lower than the rated breaking capacity.
f
8.5 Breaking capacity
A fuse-link shall be capable of breaking, at a voltage not exceeding its rated voltage, any circuit
having a prospective current between a current according to 8.4 and the rated breaking
capacity:
– for AC, test parameters are given in Table 104;
– for DC, test parameters are given in Table 105;
– for VSI applications, test parameters are given in Table 106.
8.7 I t characteristics
The values of operating I t determined as described in 9.7 shall not exceed those stated by the
manufacturer. The values of pre-arcing I t determined as described in 9.7 shall be not less than
the values stated (see 6.8.2.1 and 6.8.2.2).
8.15 Arc voltage characteristics
The arc voltage values measured as described in 9.7.5 shall not exceed those stated by the
manufacturer (see 6.9).
9 Tests
IEC 60269-1 applies with the following supplementary requirements.
IEC 60269-4:2024 © IEC 2024 – 15 –
9.1.5 Arrangement of the fuse and dimensions
The fuse-link shall be mounted open in free air in draught-free surroundings free from draughts
and, unless otherwise specified, in a vertical position (see 9.3.1). Examples of test
arrangements are given in Figure 101 and Figure 102. Test arrangements for other kinds of fuse-
links are given in IEC 60269-2 and IEC 60269-3.
9.1.6 Testing of fuse-links
9.1.6.2 Complete tests
The complete tests on fuse-links are listed in Table 102. The internal resistance of all fuse-links
shall be determined and recorded in the test report(s).
A fuse-link shall have an AC breaking capacity or a DC breaking capacity or a VSI breaking
capacity. It may have one or more of these breaking capacities.
Table 102 – List of complete tests
Test according to subclause Number of
fuse-links to
be tested
9.3 Temperature rise and power dissipation 1
9.4.3.1 a) Conventional non-fusing current 1
9.4.3.1 b) Conventional fusing current 1
9.4.3.2 Verification of rated current 1
9.4.3.5 Conventional cable overload test (for "gR" and "gS" fuse-links only) 1
For AC:
9.5 No 5 "gR" and "gS" breaking capacity and operating characteristics 1
No. 2a "aR" breaking capacity and operating characteristics 1
a
No. 2 Breaking capacity and operating characteristics
a
No. 1 Breaking capacity and operating characteristics
For DC:
9.5 No. 13 "gR" and "gS" breaking capacity and operating characteristics 1
No.12a "aR" breaking capacity and operating characteristics 1
No.12 Breaking capacity and operating characteristics 3
No.11 Breaking capacity and operating characteristics 3
For VSI fuse-links:
9.5 No. 21 Breaking capacity and operating characteristics 3
a 2
Valid for pre-arcing I t characteristics, if ambient air temperature is between 10 °C and 30 °C.
9.1.6.3 Testing of fuse-links of a homogeneous series
Fuse-links having intermediate values of rated current of a homogeneous series are exempted
from type tests if the fuse-link of the largest rated current has been tested to the requirements
of 9.1.6.2 and if the fuse-link of the smallest rated current has been submitted to the tests
indicated in Table 103.
– 16 – IEC 60269-4:2024 © IEC 2024
Table 103 – Survey of tests on fuse-links of the smallest rated current
of a homogeneous series
Number of fuse-links
Test according to subclause
to be tested
8.3 Temperature rise and power dissipation 1
9.3 Verification of temperature rise limits and power dissipation
9.3.1 Arrangement of the fuse
Only one fuse-link shall be used for the test. The fuse-link shall be mounted vertically in the
conventional test arrangement. Examples are given in Figure 101 and Figure 102.
The current density of the copper conductors forming part of the conventional test arrangement
2 2
shall be not less than 1 A/mm and not more than 1,6 A/mm , these values being based on the
rated current of the fuse-link. The ratio of width to thickness of these conductors shall not
exceed
– 10 for current ratings less than 200 A;
– 5 for current ratings 200 A and above.
The ambient air temperature during this test shall be between 10 °C and 30 °C.
When conducting the temperature-rise tests, the cross-sectional areas of the conductors
connecting the conventional test arrangement to the supply are important. The cross-sectional
area shall be selected in accordance with Table 18 of IEC 60269-1:2024, excluding the note,
and the conductors on either side of the fuse-link shall be at least 1 m long.
For fuse-links intended to be used in separate fuse-bases, the test may be performed in these
fuse-bases with conductors according to Table 18 of IEC 60269-1:2024; i
...
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