IEC 60127-8:2018
(Main)Miniature fuses - Part 8: Fuse resistors with particular overcurrent protection
Miniature fuses - Part 8: Fuse resistors with particular overcurrent protection
IEC 60127-8:2018 relates to fuse resistors with particular overcurrent protection rated up to AC 500 V and/or DC 500 V for printed circuits and other substrate systems, used for the protection of electric appliances, electronic equipment and component parts thereof, normally intended to be used indoors.
It does not apply to fuse resistors with particular overcurrent protection for appliances intended to be used under special conditions, such as in a corrosive or explosive atmosphere.
The object of this part of IEC 60127 is
a) to establish uniform requirements for fuse resistors with particular overcurrent protection so as to protect appliances or parts of appliances in the most suitable way;
b) to define the performance of the fuse resistors with particular overcurrent protection, so as to give guidance to manufacturers of electrical appliances and electronic equipment and to ensure replacement of fuse resistors with particular overcurrent protection by those of similar dimensions and characteristics;
c) to establish uniform test methods for fuse resistors with particular overcurrent protection, so as to allow verification of the values (for example rated dissipation, functioning characteristic and rated breaking capacity values) specified by the manufacturer.
This part of IEC 60127 applies in addition to the requirements of IEC 60127-1.
This first edition of IEC 60127-8 cancels and replaces IEC PAS 60127-8:2014.
This international standard is to be used in conjunction with IEC 60127-1.
Keywords: Miniature Fuses, Fuse-Resistors, Overcurrent Protection
Coupe-circuit miniatures - Partie 8: Résistances de protection avec protection particulière contre les surintensités
IEC 60127-8: 2018 porte sur les résistances de protection avec protection particulière contre les surintensités assignées jusqu’à 500 V en courant alternatif et/ou 500 V en courant continu pour les circuits imprimés et autres systèmes de substrat employés pour la protection d'appareils électriques, d’équipements électroniques et de leurs éléments constituants, normalement destinés à être utilisés à l'intérieur.
Elle n’est pas applicable aux résistances de protection avec protection particulière contre les surintensités placées dans des appareils destinés à être utilisés dans des conditions particulières, telles que des atmosphères corrosives ou explosives.
L’objet de la présente partie de l’IEC 60127 est
a) d’établir des exigences uniformes pour les résistances de protection avec protection particulière contre les surintensités afin de protéger les appareils ou les parties d’appareils de la façon la plus appropriée;
b) de définir les performances des résistances de protection avec protection particulière contre les surintensités afin de donner des recommandations aux fabricants d’appareils électriques et d'équipements électroniques et d’assurer le remplacement des résistances de protection avec protection particulière contre les surintensités par des résistances de dimensions et de caractéristiques similaires;
c) d’établir des méthodes d’essai uniformes pour les résistances de protection avec protection particulière contre les surintensités afin de permettre la vérification des valeurs spécifiées par le fabricant (par exemple, la dissipation assignée, la caractéristique de fonctionnement et le pouvoir de coupure assigné).
La présente partie de l'IEC 60127 s'applique en complément des exigences de l'IEC 60127-1.
Cette première édition de l’IEC 60127-8 annule et remplace l’IEC PAS 60127-8:2014.
La présente Norme internationale doit être utilisée conjointement avec l’IEC 60127-1.
General Information
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Standards Content (Sample)
IEC 60127-8 ®
Edition 1.0 2018-06
INTERNATIONAL
STANDARD
Miniature fuses –
Part 8: Fuse resistors with particular overcurrent protection
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
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IEC 60127-8 ®
Edition 1.0 2018-06
INTERNATIONAL
STANDARD
Miniature fuses –
Part 8: Fuse resistors with particular overcurrent protection
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.120.50 ISBN 978-2-8322-5843-9
– 2 – IEC 60127-8:2018 © IEC 2018
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 8
4 General requirements . 10
5 Standard ratings . 10
6 Marking . 11
7 General notes on tests . 11
7.1 Atmospheric conditions for testing . 11
7.2 Type tests . 11
7.2.1 General . 11
7.3 Fuse-bases for tests . 12
7.3.1 General . 12
7.3.2 General requirements . 12
7.3.3 Through-hole mounting of fuse resistors with particular overcurrent
protection . 13
7.3.4 Surface mounting of fuse resistors with particular overcurrent protection . 13
7.4 Nature of supply . 13
8 Dimensions and construction . 13
8.1 Dimensions . 13
8.1.1 Creepage distances and clearances . 13
8.2 Construction . 14
8.3 Terminations . 14
8.3.1 Through-hole mount fuse resistors with particular overcurrent protection . 15
8.3.2 Surface mount fuse resistors with particular overcurrent protection . 15
8.4 Alignment and configuration of terminations . 15
8.5 Soldered joints . 15
8.6 Solderability of terminations . 16
8.7 Resistance to soldering heat . 16
9 Electrical requirements . 16
9.1 Resistance value . 16
9.2 Functioning characteristic at the minimum breaking dissipation. 16
9.2.1 Functioning characteristic at an ambient temperature of 70 °C . 16
9.2.2 Test at elevated temperature . 16
9.2.3 Test procedure . 16
9.2.4 Presentation of results . 17
9.3 Rated breaking capacity. 17
9.3.1 Operating conditions . 17
9.3.2 Criteria for satisfactory performance . 17
9.3.3 Insulation resistance . 18
9.3.4 Dielectric strength. 18
9.4 Endurance tests . 18
9.5 Maximum sustained dissipation . 18
9.6 Pulse tests . 18
9.7 Temperature of fuse resistors with particular overcurrent protection. 18
9.8 Operating overvoltage . 19
Bibliography . 25
Figure 1 – Test board for through-hole mount fuse resistors with particular overcurrent
protection . 21
Figure 2 – Test board for surface mount fuse resistors with particular overcurrent
protection . 22
Figure 3 – Test fuse-base . 23
Figure 4 – Bending jig for surface mount fuse resistors with particular overcurrent
protection . 24
Figure 5 – Test circuit for the tests according to 9.3 . 24
Table 1 – Creepage distances and clearances (absolute minimum values) . 14
Table 2 – Test voltages for dielectric strength . 18
Table 3 – Testing schedule for individual dissipation ratings . 20
– 4 – IEC 60127-8:2018 © IEC 2018
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
MINIATURE FUSES –
Part 8: Fuse resistors with particular
overcurrent protection
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 60127-8 has been prepared by subcommittee SC 32C: Miniature
fuses, of IEC technical committee 32: Fuses
This first edition of IEC 60127-8 cancels and replaces IEC PAS 60127-8:2014.
This international standard is to be used in conjunction with IEC 60127-1.
The text of this International Standard is based on the following documents:
FDIS Report on voting
32C/542/FDIS 32C/546/RVD
Full information on the voting for the approval of this International Standard can be found in
the report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts in the IEC 60127 series, published under the general title Miniature 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 "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
A bilingual version of this publication may be issued at a later date.
– 6 – IEC 60127-8:2018 © IEC 2018
INTRODUCTION
In recent years, so-called “fuse resistors” have increasingly been used in electrical and
electronic applications. The term “fuse resistor”, however, which has become established in
the market, is misleading. The actual function of a fuse resistor is that of a resistor in an
electrical or electronic circuit. Only when an overload of multiple times the rated dissipation
occurs can fuse resistors interrupt an electric current. In a wide range between the rated
dissipation and the manufacturer’s specified breaking dissipation, fuse resistors provide poor
or no overcurrent protection. Therefore if they are incorrectly rated and improperly used in an
application, this may result in potential risk of fire.
Fuse resistors perform the function of a fuse only within a particular overcurrent range, and,
from a technical point of view, must therefore be referred to as “fuse resistors with particular
overcurrent protection”.
Fuse resistors with particular overcurrent protection can safely interrupt high short-circuit
currents, but are not capable of interrupting overload currents.
For safety reasons, they are only used in combination with an accompanying overload current
protection device, if overload currents cannot be excluded to occur in the respective
application.
MINIATURE FUSES –
Part 8: Fuse resistors with particular
overcurrent protection
1 Scope
This part of IEC 60127 relates to fuse resistors with particular overcurrent protection rated up
to AC 500 V and/or DC 500 V for printed circuits and other substrate systems, used for the
protection of electric appliances, electronic equipment and component parts thereof, normally
intended to be used indoors.
It does not apply to fuse resistors with particular overcurrent protection for appliances
intended to be used under special conditions, such as in a corrosive or explosive atmosphere.
The object of this part of IEC 60127 is
a) to establish uniform requirements for fuse resistors with particular overcurrent protection
so as to protect appliances or parts of appliances in the most suitable way;
b) to define the performance of the fuse resistors with particular overcurrent protection, so as
to give guidance to manufacturers of electrical appliances and electronic equipment and to
ensure replacement of fuse resistors with particular overcurrent protection by those of
similar dimensions and characteristics;
c) to establish uniform test methods for fuse resistors with particular overcurrent protection,
so as to allow verification of the values (for example rated dissipation, functioning
characteristic and rated breaking capacity values) specified by the manufacturer.
Manufacturers of fuse resistors with particular overcurrent protection shall ensure on their
own responsibility that their products comply with the requirements of the resistor-related
standards IEC 60115-1, IEC 60115-4-101 and IEC 60115-4-102 .
This part of IEC 60127 applies in addition to the requirements of IEC 60127-1.
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 60063:2015, Preferred number series for resistors and capacitors
IEC 60068-2-21:2006, Environmental testing – Part 2-21: Tests – Test U: Robustness of
terminations and integral mounting devices
IEC 60115-1:2008, Fixed resistors for use in electronic equipment – Part 1: Generic
specification
___________
This standard has been withdrawn.
– 8 – IEC 60127-8:2018 © IEC 2018
IEC 60115-4-101:1995, Fixed resistors for use in electronic equipment – Part 4: Detail
specification: Fixed power wirewound resistors with solderable axial wire leads – Stability
class 5%. Assessment level E
IEC 60115-4-102:1995, Fixed resistors for use in electronic equipment – Part 4: Detail
specification: Fixed power wirewound resistors with solderable axial wire leads – Stability
class 1 % – Assessment level E
IEC 60127-1:2006, Miniature fuses – Part 1: Definitions for miniature fuses and general
requirements for miniature fuse-links
IEC 60127-1:2006/AMD1:2011
IEC 60127-1:2006/AMD2:2015
IEC 60194:2015, Printed board design, manufacture and assembly – Terms and definitions
IEC 60664-1:2007, Insulation coordination for equipment within low-voltage systems – Part 1:
Principles, requirements and tests
IEC 60695-2-12:2010, Fire hazard testing – Part 2-12: Glowing/hot-wire based test methods –
Glow-wire flammability index (GWFI) test method for materials
IEC 60695-2-13:2010, Fire hazard testing – Part 2-13: Glowing/hot-wire based test methods –
Glow-wire ignition temperature (GWIT) test method for materials
IEC 60695-4:2012, Fire hazard testing – Part 4: Terminology concerning fire tests for
electrotechnical products
IEC 61249-2-7:2002, Materials for printed boards and other interconnecting structures –
Part 2-7: Reinforced base materials clad and unclad – Epoxide woven E-glass laminated
sheet of defined flammability (vertical burning test), copper-clad
3 Terms and definitions
For the purposes of this document, the terms and definitions given in Clause 3 of IEC 60127-
1:2006 as well as IEC 60115-1, IEC 60115-4-101 and IEC 60115-4-102 and the following
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
3.1
fuse resistor with particular overcurrent protection
resistor with the added function of a fuse, characterized as being capable of continuously
carrying currents up to at least the rated dissipation and of interrupting currents above a
defined multiple of the rated dissipation up to its rated breaking capacity
Note 1 to entry: Fuse resistors with particular overcurrent protection can safely interrupt high short-circuit
currents, but are not capable of interrupting overload currents. They are therefore allowed to be used only in
combination with an accompanying overload current protection device such as a miniature fuse according to parts
2, 3, 4 and 7, if overload currents cannot be excluded to occur in the respective application.
3.2
fuse resistor with particular overcurrent protection for through-hole mounting
fuse resistor with particular overcurrent protection designed for soldering directly into a
printed wiring board, with insertion of its leads in suitably designed holes
3.3
fuse resistor with particular overcurrent protection for surface mounting
fuse resistor with particular overcurrent protection designed for direct conductive attachment
by solder or other means onto the surface of a substrate, without insertion of its leads in
suitably designed holes or sockets
3.4
land
portion of a conductive pattern usually but not exclusively used for the connection and/or
attachment of components
SEE: IEC 60194
Note 1 to entry: Further definitions which may be useful in the application of surface-mount fuse resistors with
particular overcurrent protection may be found in IEC 60115-1 and IEC 60115-8.
3.5
critical resistance
resistance value at which the rated voltage is equal to the limiting element voltage
Note 1 to entry: At an ambient temperature of 70 °C, the maximum voltage which may be applied across the
terminations of a fuse resistor with particular overcurrent protection is either the calculated rated voltage, if the
resistance is less than the critical resistance, or the limiting element voltage, if the resistance is equal to or greater
than the critical resistance. At temperatures other than 70 °C, it is important that account be taken of the derating
curve and of the limiting element voltage in the calculation of any voltage to be applied
Note 2 to entry: Related terminology: Rated voltage, limiting element voltage.
3.6
limiting element voltage
U
max
maximum DC or AC r.m.s. voltage that may be continuously applied to the terminations of a
fuse resistor with particular overcurrent protection (generally dependent upon size and
manufacturing technology of the fuse resistor with particular overcurrent protection)
Note 1 to entry: Where the term "AC r.m.s. voltage" is used in this standard, the peak voltage should not exceed
1,42 times the r.m.s. value.
Note 2 to entry: This voltage can only be applied to fuse resistors with particular overcurrent protection when the
resistance value is equal to or higher than the critical resistance value.
Note 3 to entry: Related terminology: rated voltage, critical resistance.
3.7
rated resistance
resistance value for which the fuse resistor with particular overcurrent protection has been
designed, and which is generally used for denomination of the fuse resistor with particular
overcurrent protection
3.8
rated dissipation
P
maximum permissible dissipation at an ambient temperature of 70 °C under the conditions of
the respective acceptance criteria
Note 1 to entry: If the rated dissipation depends on special means supporting the abduction of the dissipation to
the environment, for example, special circuit board material, special conductor dimensions, heat-sink, such means
have to be identified whenever the rated dissipation is mentioned.
Note 2 to entry: Related terminology: rated temperature, rated voltage.
– 10 – IEC 60127-8:2018 © IEC 2018
3.9
rated temperature
maximum ambient temperature at which the rated dissipation may be applied continuously
Note 1 to entry: The rated temperature has a value of 70 °C, unless otherwise prescribed in IEC 60115-1.
Note 2 to entry: Related terminology: rated dissipation.
3.10
rated voltage
U
r
DC or AC r.m.s. voltage calculated from the square root of the product of the rated resistance
and the rated dissipation
Note 1 to entry: At high values of resistance, the rated voltage may not be applicable because of the size and the
construction of the fuse resistor with particular overcurrent protection.
Note 2 to entry: Related terminology: rated dissipation, limiting element voltage.
3.11
minimum breaking dissipation
minimum value of the breaking dissipation which is equal to a multiple of the rated dissipation
and at which the fuse resistor with particular overcurrent protection can still safely interrupt
the circuit
Note 1 to entry: In this standard the minimum breaking dissipation is specified to be 16 times the rated dissipation.
This value corresponds to the values given by most of the manufacturers.
4 General requirements
The requirements of IEC 60127-1:2006, Clause 4, are replaced as follows:
Fuse resistors with particular overcurrent protection shall be so constructed that their fuse
function is reliable and safe and they are consistent in performance at the minimum breaking
dissipation up to and including the breaking capacity rating and at any voltage up to the rated
voltage, when used within the limits of this standard.
During normal use of the fuse resistor with particular overcurrent protection and within the
conditions given in this
...
IEC 60127-8 ®
Edition 1.1 2024-07
CONSOLIDATED VERSION
INTERNATIONAL
STANDARD
colour
inside
Miniature fuses –
Part 8: Fuse resistors with particular overcurrent protection
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IEC 60127-8 ®
Edition 1.1 2024-07
CONSOLIDATED VERSION
INTERNATIONAL
STANDARD
colour
inside
Miniature fuses –
Part 8: Fuse resistors with particular overcurrent protection
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.120.50 ISBN 978-2-8322-9425-3
REDLINE VERSION – 2 – IEC 60127-8:2018+AMD1:2024 CSV
© IEC 2024
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 8
4 General requirements . 10
5 Standard ratings . 10
6 Marking . 11
7 General notes on tests . 11
7.1 Atmospheric conditions for testing . 11
7.2 Type tests . 11
7.3 Fuse-bases for tests . 12
7.3.1 General . 12
7.3.2 General requirements . 12
7.3.3 Through-hole mounting of fuse resistors with particular overcurrent
protection . 13
7.3.4 Surface mounting of fuse resistors with particular overcurrent protection . 13
7.4 Nature of supply . 13
8 Dimensions and construction . 13
8.1 Dimensions . 13
8.2 Construction . 14
8.3 Terminations . 14
8.3.1 Through-hole mount fuse resistors with particular overcurrent protection . 15
8.3.2 Surface mount fuse resistors with particular overcurrent protection . 15
8.4 Alignment and configuration of terminations . 15
8.5 Soldered joints . 15
8.6 Solderability of terminations . 16
8.7 Resistance to soldering heat . 16
9 Electrical requirements . 16
9.1 Resistance value . 16
9.2 Functioning characteristic at the minimum breaking dissipation. 16
9.2.1 Functioning characteristic at an ambient temperature of 70 °C 23 °C ±
1 °C . 16
9.2.2 Test at elevated temperature . 16
9.2.3 Test procedure . 17
9.2.4 Presentation of results . 17
9.3 Rated breaking capacity. 17
9.3.1 Operating conditions . 17
9.3.2 Criteria for satisfactory performance . 18
9.3.3 Insulation resistance . 18
9.3.4 Dielectric strength. 18
9.4 Endurance tests . 18
9.5 Maximum sustained dissipation . 18
9.6 Pulse tests . 19
9.7 Temperature of fuse resistors with particular overcurrent protection. 19
9.8 Operating overvoltage . 19
© IEC 2024
Bibliography . 26
Figure 1 – Test board for through-hole mount fuse resistors with particular overcurrent
protection . 21
Figure 2 – Test board for surface mount fuse resistors with particular overcurrent
protection . 22
Figure 3 – Test fuse-base . 24
Figure 4 – Bending jig for surface mount fuse resistors with particular overcurrent
protection . 24
Figure 5 – Test circuit for the tests according to 9.3 . 25
Table 1 – Creepage distances and clearances (absolute minimum values) . 14
Table 2 – Test voltages for dielectric strength . 18
Table 3 – Testing schedule for individual dissipation ratings . 20
REDLINE VERSION – 4 – IEC 60127-8:2018+AMD1:2024 CSV
© IEC 2024
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
MINIATURE FUSES –
Part 8: Fuse resistors with particular overcurrent protection
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 or www.iso.org/patents. IEC shall not be held responsible for identifying any or all such
patent rights.
This consolidated version of the official IEC Standard and its amendment has been
prepared for user convenience.
IEC 60127-8 edition 1.1 contains the first edition (2018-06) [documents 32C/542/FDIS
and 32C/546/RVD] and its amendment 1 (2024-07) [documents 32C/638/FDIS and
32C/642/RVD].
In this Redline version, a vertical line in the margin shows where the technical content
is modified by amendment 1. Additions are in green text, deletions are in strikethrough
red text. A separate Final version with all changes accepted is available in this
publication.
© IEC 2024
International Standard IEC 60127-8 has been prepared by subcommittee SC 32C: Miniature
fuses, of IEC technical committee 32: Fuses
This first edition of IEC 60127-8 cancels and replaces IEC PAS 60127-8:2014.
This international standard is to be used in conjunction with IEC 60127-1.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts in the IEC 60127 series, published under the general title Miniature fuses,
can be found on the IEC website.
The committee has decided that the contents of this document and its amendment 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 publication indicates
that it contains colours which are considered to be useful for the correct
understanding of its contents. Users should therefore print this document using a
colour printer.
REDLINE VERSION – 6 – IEC 60127-8:2018+AMD1:2024 CSV
© IEC 2024
INTRODUCTION
In recent years, so-called “fuse resistors” have increasingly been used in electrical and
electronic applications. The term “fuse resistor”, however, which has become established in
the market, is misleading. The actual function of a fuse resistor is that of a resistor in an
electrical or electronic circuit. Only when an overload of multiple times the rated dissipation
occurs can fuse resistors interrupt an electric current. In a wide range between the rated
dissipation and the manufacturer’s specified breaking dissipation, fuse resistors provide poor
or no overcurrent protection. Therefore if they are incorrectly rated and improperly used in an
application, this may result in potential risk of fire.
Fuse resistors perform the function of a fuse only within a particular overcurrent range, and,
from a technical point of view, must therefore be referred to as “fuse resistors with particular
overcurrent protection”.
Fuse resistors with particular overcurrent protection can safely interrupt high short-circuit
currents, but are not capable of interrupting overload currents.
For safety reasons, they are only used in combination with an accompanying overload current
protection device, if overload currents cannot be excluded to occur in the respective
application.
© IEC 2024
MINIATURE FUSES –
Part 8: Fuse resistors with particular overcurrent protection
1 Scope
This part of IEC 60127 relates to fuse resistors with particular overcurrent protection rated up
to AC 500 V and/or DC 500 V for printed circuits and other substrate systems, used for the
protection of electric appliances, electronic equipment and component parts thereof, normally
intended to be used indoors.
It does not apply to fuse resistors with particular overcurrent protection for appliances
intended to be used under special conditions, such as in a corrosive or explosive atmosphere.
The object of this part of IEC 60127 is
a) to establish uniform requirements for fuse resistors with particular overcurrent protection
so as to protect appliances or parts of appliances in the most suitable way;
b) to define the performance of the fuse resistors with particular overcurrent protection, so as
to give guidance to manufacturers of electrical appliances and electronic equipment and to
ensure replacement of fuse resistors with particular overcurrent protection by those of
similar dimensions and characteristics;
c) to establish uniform test methods for fuse resistors with particular overcurrent protection,
so as to allow verification of the values (for example rated dissipation, functioning
characteristic and rated breaking capacity values) specified by the manufacturer.
With exceptions of 3.5 and 3.8 of IEC 60127-1:2023, manufacturers of fuse resistors with
particular overcurrent protection shall ensure on their own responsibility that their products
comply with the requirements of the resistor-related standards IEC 60115-1, IEC 60115-4-
1 1
101 and IEC 60115-4-102 .
Fuse resistors with particular overcurrent protection are not intended to be replaced by the
end-user of an electrical / electronic appliance.
This part of IEC 60127 applies in addition to the requirements of IEC 60127-1.
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 60063:2015, Preferred number series for resistors and capacitors
IEC 60068-2-21:2006, Environmental testing – Part 2-21: Tests – Test U: Robustness of
terminations and integral mounting devices
IEC 60115-1:2008, Fixed resistors for use in electronic equipment – Part 1: Generic
specification
___________
IEC 60115-4-101 and IEC 60115-4-102 have been withdrawn.
REDLINE VERSION – 8 – IEC 60127-8:2018+AMD1:2024 CSV
© IEC 2024
IEC 60115-4-101:1995, Fixed resistors for use in electronic equipment – Part 4: Detail
specification: Fixed power wirewound resistors with solderable axial wire leads – Stability
class 5%. Assessment level E
IEC 60115-4-102:1995, Fixed resistors for use in electronic equipment – Part 4: Detail
specification: Fixed power wirewound resistors with solderable axial wire leads – Stability
class 1 % – Assessment level E
IEC 60127-1:2006, Miniature fuses – Part 1: Definitions for miniature fuses and general
requirements for miniature fuse-links
IEC 60127-1:2006/AMD1:2011
IEC 60127-1:2006/AMD2:2015
IEC 60194:2015, Printed board design, manufacture and assembly – Terms and definitions
IEC 60664-1:2007, Insulation coordination for equipment within low-voltage systems – Part 1:
Principles, requirements and tests
IEC 60695-2-12:2010, Fire hazard testing – Part 2-12: Glowing/hot-wire based test methods –
Glow-wire flammability index (GWFI) test method for materials
IEC 60695-2-13:2010, Fire hazard testing – Part 2-13: Glowing/hot-wire based test methods –
Glow-wire ignition temperature (GWIT) test method for materials
IEC 60695-4:2012, Fire hazard testing – Part 4: Terminology concerning fire tests for
electrotechnical products
IEC 61249-2-7:2002, Materials for printed boards and other interconnecting structures –
Part 2-7: Reinforced base materials clad and unclad – Epoxide woven E-glass laminated
sheet of defined flammability (vertical burning test), copper-clad
3 Terms and definitions
With the exceptions of 3.5 and 3.8 of IEC 60127-1:2023, for the purposes of this document,
the terms and definitions given in Clause 3 of IEC 60127-1:20062023 as well as resistor-
related standards IEC 60115-1, IEC 60115-4-101 and IEC 60115-4-102, and the following
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
3.1
fuse resistor with particular overcurrent protection
resistor with the added function of a fuse, characterized as being capable of continuously
carrying currents up to at least the rated dissipation and of interrupting currents above a
defined multiple of the rated dissipation up to its rated breaking capacity
Note 1 to entry: Fuse resistors with particular overcurrent protection can safely interrupt high short-circuit
currents, but are not capable of interrupting overload currents. They are therefore allowed to be used only in
combination with an accompanying overload current protection device such as a miniature fuse according to parts
IEC 60127-2, −3, −4 and −7, if overload currents cannot be excluded to occur in the respective application.
© IEC 2024
3.2
fuse resistor with particular overcurrent protection for through-hole mounting
fuse resistor with particular overcurrent protection designed for soldering directly into a
printed wiring board, with insertion of its leads in suitably designed holes
3.3
fuse resistor with particular overcurrent protection for surface mounting
fuse resistor with particular overcurrent protection designed for direct conductive attachment
by solder or other means onto the surface of a substrate, without insertion of its leads in
suitably designed holes or sockets
3.4
land
portion of a conductive pattern usually but not exclusively used for the connection and/or
attachment of components
SEE: IEC 60194
Note 1 to entry: Further definitions which may be useful in the application of surface-mount fuse resistors with
particular overcurrent protection may be found in IEC 60115-1 and IEC 60115-8.
3.5
critical resistance
resistance value at which the rated voltage is equal to the limiting element voltage
Note 1 to entry: At an ambient temperature of 70 (23±1) °C, the maximum voltage which may be applied across
the terminations of a fuse resistor with particular overcurrent protection is either the calculated rated voltage, if the
resistance is less than the critical resistance, or the limiting element voltage, if the resistance is equal to or greater
than the critical resistance. At temperatures other than 70 (23±1) °C, it is important that account be taken of the
derating curve and of the limiting element voltage in the calculation of any voltage to be applied.
Note 2 to entry: Related terminology: Rated voltage, limiting element voltage.
3.6
limiting element voltage
U
max
maximum DC or AC r.m.s. voltage that may be continuously applied to the terminations of a
fuse resistor with particular overcurrent protection (generally dependent upon size and
manufacturing technology of the fuse resistor with particular overcurrent protection)
Note 1 to entry: Where the term "AC r.m.s. voltage" is used in this standard, the peak voltage should not exceed
1,42 times the r.m.s. value.
Note 2 to entry: This voltage can only be applied to fuse resistors with particular overcurrent protection when the
resistance value is equal to or higher than the critical resistance value.
Note 3 to entry: Related terminology: rated voltage, critical resistance.
3.7
rated resistance
resistance value for which the fuse resistor with particular overcurrent protection has been
designed, and which is generally used for denomination of the fuse resistor with particular
overcurrent protection
3.8
rated dissipation
P
maximum permissible dissipation at an ambient temperature of 70 °C under the conditions of
the respective acceptance criteria
Note 1 to entry: If the rated dissipation depends on special means supporting the abduction of the dissipation to
the environment, for example, special circuit board material, special conductor dimensions, heat-sink, such means
have to be identified whenever the rated dissipation is mentioned.
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© IEC 2024
Note 2 to entry: Related terminology: rated temperature, rated voltage.
3.9
rated temperature
maximum ambient temperature at which the rated dissipation may be applied continuously
Note 1 to entry: The rated temperature has a value of 70°C (23±1) °C, unless otherwise prescribed in IEC 60115-
1.
Note 2 to entry: Related terminology: rated dissipation.
3.10
rated voltage
U
r
DC or AC r.m.s. voltage calculated from the square root of the product of the rated resistance
and the rated dissipation
Note 1 to entry: At high values of resistance, the rated voltage may not be applicable because of the size and the
construction of the fuse resistor with particular overcurrent protection.
Note 2 to entry: Related terminology: rated dissipation, limiting element voltage.
3.11
minimum breaking dissipation
minimum value of the breaking dissipation which is equal to a multiple of the rated dissipation
and at which the fuse resistor with particular overcurrent protection can still safely interrupt
the circuit
Note 1 to entry: In this standard the minimum breaking dissipation is specified to be 16 times the rated dissipation.
This value corresponds to the values given by most of the manufacturers.
4 General requirements
The requirements of IEC 60127-1:2006, Clause 4, are replaced as follows:
Fuse resistors with particular overcurrent protection shall be so constructed that their fuse
function is reliable and safe and they are consistent in performance at the minimum breaking
dissipation up to and including the breaking capacity rating and at any voltage up to the rated
voltage, when used within the limits of this standard.
During normal use of the fuse resistor with particular overcurrent protection and within the
conditions given in this standard, no permanent arc, nor external arcing, nor any flame that
can endanger the surroundings, shall be produced. During testing and after operation, the
fuse resistor with particular overcurrent protection shall not have suffered damage and the
surroundings shall be unimpaired. Marking shall still be legible.
In general, compliance is checked by carrying out all the tests specified.
5 Standard ratings
The values of rated resistance shall be selected from the E12 or E24 series as given in
IEC 60063.
© IEC 2024
6 Marking
The requirements of IEC 60127-1:2006, Clause 6, are replaced as follows:
6.1 Each fuse resistor with particular overcurrent protection shall be marked as follows:
a) Rated resistance in ohms (abbreviation Ω or mΩ).
b) The marking of the tolerance on rated resistance shall follow and be adjacent to the
marking of the rated resistance.
c) Rated dissipation in watts (W).
d) Manufacturer's name or trade mark.
e) The symbol “F” shall precede and be adjacent to the marking of the rated resistance.
6.2 Marking shall be indelible and easily legible.
In the case of screen or pad printing, compliance is checked by inspection and by rubbing the
marking by hand for 15 s with a piece of cloth soaked in water and again for 15 s with a piece
of cloth soaked in petroleum spirit.
NOTE 1 For petroleum spirit the use of an aliphatic solvent hexane, with an aromatics content of maximum 0,1 %
volume, a kauri-butanol value of 29, initial boiling point approximately 65 °C, dry-point approximately 69 °C and
specific gravity of approximately 0,68 is recommended.
NOTE 2 For all other printing techniques, the above test is not applicable.
6.3 The marking according to 6.2 6.1 shall also be printed on the packing together with a
reference to this standard document. The marking of the rated resistance on the packing shall
include the abbreviation Ω or mΩ. In addition, the marking of the rated voltage, rated
dissipation P P and minimum breaking dissipation shall be printed on the packing.
70 23±1 °C
Compliance is checked by inspection.
6.4 For colour coding, no test or requirement is specified tests and requirements are under
consideration.
6.5 Where marking is impracticable due to space limitations, the relevant information
should appear on the smallest packing unit and in the manufacturer’s technical literature.
7 General notes on tests
7.1 Atmospheric conditions for testing
See IEC 60127-1:2006, 7.1.
7.2 Type tests
7.2.1 General
The requirements of IEC 60127-1:2006, 7.2, are replaced as follows:
7.2.2 For fuse resistors with particular overcurrent protection designed and rated both for
AC and DC, the number of fuse resistors with particular overcurrent protection required is 45.
For fuse resistors with particular overcurrent protection designed only for AC or DC, the
number of fuse resistors with particular overcurrent protection required is 36.
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© IEC 2024
18 fuse resistors with particular overcurrent protection are kept as spares.
The fuse resistors with particular overcurrent protection shall be tested or inspected in
accordance with the following subclauses:
a) Marking (see 6.1);
b) Dimensions (see 8.1);
c) Construction (see 8.2);
d) Resistance (see 9.1);
with such additional tests as are specified in Subclauses 7.2.3 to 7.4.
7.2.3 Testing of the minimum and maximum rated resistance of the fuse resistors with
particular overcurrent protection shall then be performed according to the testing schedule
shown in Table 3.
In addition, any one rated resistance value per resistance decade shall be tested.
7.2.4
a) No failure is allowed in any of the tests covered by 8.1.1, 9.1, 9.2 and 9.3.
b) If in the test covered by Clause 6 and those tests described in 8.1 and 8.3, one failure
occurs, the test shall be repeated on twice the number of fuse resistors with particular
overcurrent protection, at the same breaking dissipation and a second failure shall be a
cause for rejection.
If two failures occur, but not both in the same test, the fuse resistors with particular
overcurrent protection shall be deemed to comply provided that there are no further
failures in repeat tests with twice the number of test samples.
If more than two failures occur, the fuse resistors with particular overcurrent protection
shall be deemed not to comply with this standard.
7.3 Fuse-bases for tests
7.3.1 General
The requirements of IEC 60127-1:2006, 7.3, are replaced as follows:
7.3.2 General requirements
The fuse resistors with particular overcurrent protection shall be mounted upon the
appropriate test board (see 7.3.3 or 7.3.4 as appropriate) by soldering.
This test board shall then be mounted on the test fuse-base (Figure 3). The test board shall
be made of epoxide woven glass fabric copper-clad laminated sheet, as defined in
IEC 61249-2-7.
• The nominal sheet thickness shall be 1,6 mm.
• The nominal thickness of copper layer shall be 0,035 mm or 0,070 mm for rated
dissipation values above 5 W for rated power dissipation below 5 W; 0,070 mm for rated
dissipation 5 W up to 10 W.
Metal parts of the fuse-base shall be made of brass with a copper content between 58 % and
70 %. Contact parts shall be silver-plated.
When two or more fuse resistors with particular overcurrent protection are tested in series,
the test fuse-bases shall be located so that there will be a spacing of not less than 50 mm
between any two fuse resistors with particular overcurrent protection. The conductor
connecting the test fuse-bases together, and connecting the test fuse-bases to the ammeter
© IEC 2024
and the source of supply shall be insulated copper wire. The length of each conductor shall be
250 mm, and the cross-sectional area of the wire shall be approximately 1 mm .
7.3.3 Through-hole mounting of fuse resistors with particular overcurrent protection
For electrical tests, the fuse resistors with particular overcurrent protection shall be mounted
on the test board as shown in Figure 1 in the pair of holes appropriate to the spacing of the
terminations.
7.3.4 Surface mounting of fuse resistors with particular overcurrent protection
For electrical tests, the fuse resistors with particular overcurrent protection shall be mounted
on the test board as shown in Figure 2.
7.4 Nature of supply
See IEC 60127-1:2006, 7.4.
8 Dimensions and construction
8.1 Dimensions
The requirements of IEC 60127-1:2006, 8.1, are replaced as follows:
• The dimensions of the fuse resistors with particular overcurrent protection shall be as
specified by the manufacturer.
• Compliance is checked by measurement of length, width and height.
For through-hole mount fuse resistors with particular overcurrent protection the termination
spacing is checked. In addition, the following applies:
• The termination shall also pass through a 1 mm hole.
• The length of the termination is not specified as this is subject to the method of packaging.
8.1.1 Creepage distances and clearances
The creepage distances and clearances between current-carrying parts (contacts together
with their terminals) and the outside of the enclosure of the fuse resistor with particular
overcurrent protection including insulated metal parts thereof, shall be not less than the
values given in Table 1. The values indicated are absolute minimum values and inclusive of
manufacturing tolerances.
These distances do not apply across the disconnection (between the open contacts) of the
fuse resistors with particular overcurrent protection.
Compliance is checked by measuring the distances concerned.
REDLINE VERSION – 14 – IEC 60127-8:2018+AMD1:2024 CSV
© IEC 2024
Table 1 – Creepage distances and clearances
(absolute minimum values)
Rated voltage, U Clearance Creepage distance
r
V mm mm
0 to 32 0,2 0,53
33 to 50 0,2 1,2
51 to 125 0,5 1,5
126 to 250 1,5 2,5
251 to 400 3,0 4,0
401 to 500 4,0 6,9
NOTE 1 The clearances/creepage distances are specified according to IEC 60664-1.
NOTE 2 The values specified are for typical applications of fuse resistors with particular overcurrent protection
assuming:
a) continuous voltage stress;
b) altitude of 2 000 m;
c) basic insulation;
d) inhomogeneous field;
e) overvoltage category II;
f) pollution degree 2;
g) material group III.
NOTE 3 If conditions are different from those specified in note 2, adjustments in clearances/creepage distances
will be necessary as per IEC 60664-1.
8.2 Construction
The requirements of IEC 60127-1:2006, 8.2, are replaced as follows:
The fuse resistor with particular overcurrent protection shall be completely enclosed.
8.2.1 The fuse resistor with particular overcurrent protection shall be resistant to fire
according to IEC 60695-2-12 and IEC 60695-2-13.
Compliance is checked by inspection. This is not applicable for fuse resistors with particular
overcurrent protection which represent small parts according to IEC 60695-4:2012, 3.78.
For fuse resistor bodies made of plastic material or of material containing organic substances,
the following minimum requirements apply:
• Glow-wire ignition temperature (GWIT) = 775 °C
• Glow-wire flammability index (GWFI) = 850 °C
NOTE 1 For the glow wire tests, the material plates with dimensions according to IEC 60695-2-12:2010, 4.2
and/or IEC 60695-2-13:2010, 4.2, are used.
NOTE 2 For materials such as glass and ceramic whose GWIT and GWFI are thought to be higher than 775 °C
and respectively 850 °C the glow-wire tests do not apply.
8.3 Terminations
The requirements of IEC 60127-1:2006, 8.3, are replaced as follows:
© IEC 2024
8.3.1 Through-hole mount fuse resistors with particular overcurrent protection
The terminations shall be firmly attached so that it is not possible to remove them without
damaging the fuse resistor with particular overcurrent protection.
Compliance is checked by carrying out the following test.
The tests are carried out in accordance with IEC 60068-2-21.
The following tests shall be applied:
• tensile test Ua , applied force 10 N;
• thrust test Ua , applied force 2 N;
• bending test Ub, applied force 5 N, number of bends: 1.
The sample size is two fuse resistors with particular overcurrent protection for each test. After
testing, the terminations shall remain firmly attached. The resistance shall be measured in
accordance with 9.1, and the change in resistance shall not exceed the value specified by the
manufacturer. Bending test Ub is omitted, if the terminations are less than 5 mm.
The samples are then mounted on the test board as shown in Figure 1.
8.3.2 Surface mount fuse resistors with particular overcurrent protection
The fuse resistors with particular overcurrent protection shall be mounted on the test board as
shown in Figure 2. The test board, with the fuse resistors with particular overcurrent
protection on the underside, shall be placed in the bending jig as shown in Figure 4. The test
board shall then be bent by 1 mm at a rate of 1 mm/s. The test board shall be allowed to
recover from the bent position, and then be removed from the test jig.
After testing, the terminations shall remain firmly attached. The resistance shall be measured
in accordance with 9.1, and the change in resistance shall not exceed the value specified by
the manufacturer.
8.4 Alignment and configuration of terminations
The termination configuration and spacing shall be as specified by the manufacturer.
NOTE 1 Through-hole mounting of fuse resistors with particular overcurrent protection
For through-hole mounting of fuse resistors with particular overcurrent protection, the dimensions specified by the
manufacturer are such as to permit installation on printed circuit boards having a grid system of holes located on
centres of distance e = 2,5 mm. Attention is drawn to the fact that in some parts of the world the value e = 2,54 mm
is still in use by printed circuit designers.
Electrical and electronic circuit designers are advised to apply the requirements of IEC 60326-3 .
NOTE 2 Surface mounting of fuse resistors with particular overcurrent protection
For surface mounting of fuse resistors with particular overcurrent protection, electrical and electronic circuit
designers are advised to design substrate land areas to receive the fuse resistor with particular overcurrent
protection with due consideration for achieving the maximum area of contact in the application, taking into account
the tolerance applied to mechanical placing of the component and the dimensions and tolerances for terminals in
this standard.
8.5 Soldered joints
No test specified.
___________
This standard has been withdrawn.
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© IEC 2024
8.6 Solderability of terminations
No test specified.
8.7 Resistance to soldering heat
No test specified.
9 Electrical requirements
The requirements of IEC 60127-1:2006, Clause 9, are replaced as follows:
9.1 Resistance value
The samples are drawn at random and numbered consecutively (without being sorted in
descending order of resistance value). The resistance value shall be measured at the points
marked U in Figure 1 for through-hole mount fuse resistors with particular overcurrent
protection and in Figure 2 for surface mount fuse resistors with particular overcurrent
protection, using the test fuse-base shown in Figure 3 (see 7.3).
Resistance values including tolerances as specified by the manufacturer apply.
9.2 Functioning characteristic at the minimum breaking dissipation
9.2.1 Functioning characteristic at an ambient temperature of 70 °C 23 °C ± 1 °C
The breaking dissipation across the fuse resistor with particular overcurrent protection shall
be adjusted to within ± 1 % of the value required in this standard document. The breaking
dissipation stability during the test shall be maintained within ± 1 % of the adjusted value.
The accuracy of the measurement of time shall be within a tolerance of ± 5 % for times of less
than 10 s and ± 2 % for times of 10 s or more.
Compliance is checked as follows:
+0
a) The samples are exposed in the test oven to a temperature of 70 until the temperature
−5
has stabilized, shown when two consecutive readings are equal within 1 K.
a) After stabilization of the test oven at 70 °C, An initial load of 16 times the rated dissipation
is applied across the sample.
NOTE To adjust the initial load it could be necessary to use a separate resistor which is less heat-sensitive
than the test sample.
For the measurement it is necessary to apply the test load for a minimum of 50 ms.
b) The temperature rise, as measured on the terminations where they enter the test board,
shall not exceed 180 °C or 135 K 157 K taking into account the standard use of SnAgCu
or SnCu based solders.
c) In addition, the measured operating times shall not exceed the maximum values specified
by the manufacturer and shall be not more than 60 s.
d) Subsequent assessment according to 9.3.2 and testing according to 9.3.3 and 9.3.3.1
9.3.4.
9.2.2 Test at elevated temperature
None specified.
© IEC 2024
9.2.3 Test procedure
The requirements of IEC 60127-1:2006, 9.2.3, are replaced as follows:
Direct current shall be used for these tests.
NOTE Direct current is used because it is easier to control and eliminates the variation inherent with alternating
current caused by the point on the voltage wave that switching occurs.
9.2.4 Presentation of results
Not applicable.
9.3 Rated breaking capacity
9.3.1 Operating conditions
The requirements of IEC 60127-1:2006, 9.3.1, are replaced as follows:
Fuse resistors with particular overcurrent protection shall operate satisfactorily without
endangering the surroundings when breaking a prospective current of 35 A at the rated
voltage but not less than AC 250 V and/or DC 250 V.
The recovery voltage shall be between 1,02 and 1,05 times the rated voltage of the fuse
resistor with particular overcurrent
...
IEC 60127-8 ®
Edition 1.0 2018-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Miniature fuses –
Part 8: Fuse resistors with particular overcurrent protection
Coupe-circuit miniatures –
Partie 8: Résistances de protection avec protection particulière contre les
surintensités
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IEC 60127-8 ®
Edition 1.0 2018-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Miniature fuses –
Part 8: Fuse resistors with particular overcurrent protection
Coupe-circuit miniatures –
Partie 8: Résistances de protection avec protection particulière contre les
surintensités
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.120.50 ISBN 978-2-8322-6238-2
– 2 – IEC 60127-8:2018 © IEC 2018
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 8
4 General requirements . 10
5 Standard ratings . 10
6 Marking . 11
7 General notes on tests . 11
7.1 Atmospheric conditions for testing . 11
7.2 Type tests . 11
7.2.1 General . 11
7.3 Fuse-bases for tests . 12
7.3.1 General . 12
7.3.2 General requirements . 12
7.3.3 Through-hole mounting of fuse resistors with particular overcurrent
protection . 13
7.3.4 Surface mounting of fuse resistors with particular overcurrent protection . 13
7.4 Nature of supply . 13
8 Dimensions and construction . 13
8.1 Dimensions . 13
8.1.1 Creepage distances and clearances . 13
8.2 Construction . 14
8.3 Terminations . 14
8.3.1 Through-hole mount fuse resistors with particular overcurrent protection . 15
8.3.2 Surface mount fuse resistors with particular overcurrent protection . 15
8.4 Alignment and configuration of terminations . 15
8.5 Soldered joints . 15
8.6 Solderability of terminations . 16
8.7 Resistance to soldering heat . 16
9 Electrical requirements . 16
9.1 Resistance value . 16
9.2 Functioning characteristic at the minimum breaking dissipation. 16
9.2.1 Functioning characteristic at an ambient temperature of 70 °C . 16
9.2.2 Test at elevated temperature . 16
9.2.3 Test procedure . 16
9.2.4 Presentation of results . 17
9.3 Rated breaking capacity. 17
9.3.1 Operating conditions . 17
9.3.2 Criteria for satisfactory performance . 17
9.3.3 Insulation resistance . 18
9.3.4 Dielectric strength. 18
9.4 Endurance tests . 18
9.5 Maximum sustained dissipation . 18
9.6 Pulse tests . 18
9.7 Temperature of fuse resistors with particular overcurrent protection. 18
9.8 Operating overvoltage . 19
Bibliography . 25
Figure 1 – Test board for through-hole mount fuse resistors with particular overcurrent
protection . 21
Figure 2 – Test board for surface mount fuse resistors with particular overcurrent
protection . 22
Figure 3 – Test fuse-base . 23
Figure 4 – Bending jig for surface mount fuse resistors with particular overcurrent
protection . 24
Figure 5 – Test circuit for the tests according to 9.3 . 24
Table 1 – Creepage distances and clearances (absolute minimum values) . 14
Table 2 – Test voltages for dielectric strength . 18
Table 3 – Testing schedule for individual dissipation ratings . 20
– 4 – IEC 60127-8:2018 © IEC 2018
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
MINIATURE FUSES –
Part 8: Fuse resistors with particular
overcurrent protection
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 60127-8 has been prepared by subcommittee SC 32C: Miniature
fuses, of IEC technical committee 32: Fuses
This bilingual version (2018-12) corresponds to the monolingual English version, published in
2018-06.
This first edition of IEC 60127-8 cancels and replaces IEC PAS 60127-8:2014.
This international standard is to be used in conjunction with IEC 60127-1.
The text of this International Standard is based on the following documents:
FDIS Report on voting
32C/542/FDIS 32C/546/RVD
Full information on the voting for the approval of this International Standard can be found in
the report on voting indicated in the above table.
The French version of this standard has not been voted upon.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts in the IEC 60127 series, published under the general title Miniature 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 "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
– 6 – IEC 60127-8:2018 © IEC 2018
INTRODUCTION
In recent years, so-called “fuse resistors” have increasingly been used in electrical and
electronic applications. The term “fuse resistor”, however, which has become established in
the market, is misleading. The actual function of a fuse resistor is that of a resistor in an
electrical or electronic circuit. Only when an overload of multiple times the rated dissipation
occurs can fuse resistors interrupt an electric current. In a wide range between the rated
dissipation and the manufacturer’s specified breaking dissipation, fuse resistors provide poor
or no overcurrent protection. Therefore if they are incorrectly rated and improperly used in an
application, this may result in potential risk of fire.
Fuse resistors perform the function of a fuse only within a particular overcurrent range, and,
from a technical point of view, must therefore be referred to as “fuse resistors with particular
overcurrent protection”.
Fuse resistors with particular overcurrent protection can safely interrupt high short-circuit
currents, but are not capable of interrupting overload currents.
For safety reasons, they are only used in combination with an accompanying overload current
protection device, if overload currents cannot be excluded to occur in the respective
application.
MINIATURE FUSES –
Part 8: Fuse resistors with particular
overcurrent protection
1 Scope
This part of IEC 60127 relates to fuse resistors with particular overcurrent protection rated up
to AC 500 V and/or DC 500 V for printed circuits and other substrate systems, used for the
protection of electric appliances, electronic equipment and component parts thereof, normally
intended to be used indoors.
It does not apply to fuse resistors with particular overcurrent protection for appliances
intended to be used under special conditions, such as in a corrosive or explosive atmosphere.
The object of this part of IEC 60127 is
a) to establish uniform requirements for fuse resistors with particular overcurrent protection
so as to protect appliances or parts of appliances in the most suitable way;
b) to define the performance of the fuse resistors with particular overcurrent protection, so as
to give guidance to manufacturers of electrical appliances and electronic equipment and to
ensure replacement of fuse resistors with particular overcurrent protection by those of
similar dimensions and characteristics;
c) to establish uniform test methods for fuse resistors with particular overcurrent protection,
so as to allow verification of the values (for example rated dissipation, functioning
characteristic and rated breaking capacity values) specified by the manufacturer.
Manufacturers of fuse resistors with particular overcurrent protection shall ensure on their
own responsibility that their products comply with the requirements of the resistor-related
standards IEC 60115-1, IEC 60115-4-101 and IEC 60115-4-102 .
This part of IEC 60127 applies in addition to the requirements of IEC 60127-1.
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 60063:2015, Preferred number series for resistors and capacitors
IEC 60068-2-21:2006, Environmental testing – Part 2-21: Tests – Test U: Robustness of
terminations and integral mounting devices
IEC 60115-1:2008, Fixed resistors for use in electronic equipment – Part 1: Generic
specification
___________
This standard has been withdrawn.
– 8 – IEC 60127-8:2018 © IEC 2018
IEC 60115-4-101:1995, Fixed resistors for use in electronic equipment – Part 4: Detail
specification: Fixed power wirewound resistors with solderable axial wire leads – Stability
class 5%. Assessment level E
IEC 60115-4-102:1995, Fixed resistors for use in electronic equipment – Part 4: Detail
specification: Fixed power wirewound resistors with solderable axial wire leads – Stability
class 1 % – Assessment level E
IEC 60127-1:2006, Miniature fuses – Part 1: Definitions for miniature fuses and general
requirements for miniature fuse-links
IEC 60127-1:2006/AMD1:2011
IEC 60127-1:2006/AMD2:2015
IEC 60194:2015, Printed board design, manufacture and assembly – Terms and definitions
IEC 60664-1:2007, Insulation coordination for equipment within low-voltage systems – Part 1:
Principles, requirements and tests
IEC 60695-2-12:2010, Fire hazard testing – Part 2-12: Glowing/hot-wire based test methods –
Glow-wire flammability index (GWFI) test method for materials
IEC 60695-2-13:2010, Fire hazard testing – Part 2-13: Glowing/hot-wire based test methods –
Glow-wire ignition temperature (GWIT) test method for materials
IEC 60695-4:2012, Fire hazard testing – Part 4: Terminology concerning fire tests for
electrotechnical products
IEC 61249-2-7:2002, Materials for printed boards and other interconnecting structures –
Part 2-7: Reinforced base materials clad and unclad – Epoxide woven E-glass laminated
sheet of defined flammability (vertical burning test), copper-clad
3 Terms and definitions
For the purposes of this document, the terms and definitions given in Clause 3 of IEC 60127-
1:2006 as well as IEC 60115-1, IEC 60115-4-101 and IEC 60115-4-102 and the following
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
3.1
fuse resistor with particular overcurrent protection
resistor with the added function of a fuse, characterized as being capable of continuously
carrying currents up to at least the rated dissipation and of interrupting currents above a
defined multiple of the rated dissipation up to its rated breaking capacity
Note 1 to entry: Fuse resistors with particular overcurrent protection can safely interrupt high short-circuit
currents, but are not capable of interrupting overload currents. They are therefore allowed to be used only in
combination with an accompanying overload current protection device such as a miniature fuse according to parts
2, 3, 4 and 7, if overload currents cannot be excluded to occur in the respective application.
3.2
fuse resistor with particular overcurrent protection for through-hole mounting
fuse resistor with particular overcurrent protection designed for soldering directly into a
printed wiring board, with insertion of its leads in suitably designed holes
3.3
fuse resistor with particular overcurrent protection for surface mounting
fuse resistor with particular overcurrent protection designed for direct conductive attachment
by solder or other means onto the surface of a substrate, without insertion of its leads in
suitably designed holes or sockets
3.4
land
portion of a conductive pattern usually but not exclusively used for the connection and/or
attachment of components
SEE: IEC 60194
Note 1 to entry: Further definitions which may be useful in the application of surface-mount fuse resistors with
particular overcurrent protection may be found in IEC 60115-1 and IEC 60115-8.
3.5
critical resistance
resistance value at which the rated voltage is equal to the limiting element voltage
Note 1 to entry: At an ambient temperature of 70 °C, the maximum voltage which may be applied across the
terminations of a fuse resistor with particular overcurrent protection is either the calculated rated voltage, if the
resistance is less than the critical resistance, or the limiting element voltage, if the resistance is equal to or greater
than the critical resistance. At temperatures other than 70 °C, it is important that account be taken of the derating
curve and of the limiting element voltage in the calculation of any voltage to be applied
Note 2 to entry: Related terminology: Rated voltage, limiting element voltage.
3.6
limiting element voltage
U
max
maximum DC or AC r.m.s. voltage that may be continuously applied to the terminations of a
fuse resistor with particular overcurrent protection (generally dependent upon size and
manufacturing technology of the fuse resistor with particular overcurrent protection)
Note 1 to entry: Where the term "AC r.m.s. voltage" is used in this standard, the peak voltage should not exceed
1,42 times the r.m.s. value.
Note 2 to entry: This voltage can only be applied to fuse resistors with particular overcurrent protection when the
resistance value is equal to or higher than the critical resistance value.
Note 3 to entry: Related terminology: rated voltage, critical resistance.
3.7
rated resistance
resistance value for which the fuse resistor with particular overcurrent protection has been
designed, and which is generally used for denomination of the fuse resistor with particular
overcurrent protection
3.8
rated dissipation
P
maximum permissible dissipation at an ambient temperature of 70 °C under the conditions of
the respective acceptance criteria
Note 1 to entry: If the rated dissipation depends on special means supporting the abduction of the dissipation to
the environment, for example, special circuit board material, special conductor dimensions, heat-sink, such means
have to be identified whenever the rated dissipation is mentioned.
Note 2 to entry: Related terminology: rated temperature, rated voltage.
– 10 – IEC 60127-8:2018 © IEC 2018
3.9
rated temperature
maximum ambient temperature at which the rated dissipation may be applied continuously
Note 1 to entry: The rated temperature has a value of 70 °C, unless otherwise prescribed in IEC 60115-1.
Note 2 to entry: Related terminology: rated dissipation.
3.10
rated voltage
U
r
DC or AC r.m.s. voltage calculated from the square root of the product of the rated resistance
and the rated dissipation
Note 1 to entry: At high values of resistance, the rated voltage may not be applicable because of the size and the
construction of the fuse resistor with particular overcurrent protection.
Note 2 to entry: Related terminology: rated dissipation, limiting element voltage.
3.11
minimum breaking dissipation
minimum value of the breaking dissipation which is equal to a multiple of the rated dissipation
and at which the fuse resistor with particular overcurrent protection can still safely interrupt
the circuit
Note 1 to entry: In this standard the minimum breaking dissipation is specified to be 16 times the rated dissipation.
This value corresponds to the values given by most of the manufacturers.
4 General requirements
The requirements of IEC 60127-1:2006, Clause 4, are replaced as follows:
Fuse resistors with particular overcurrent protection shall be so constructed that their fuse
function is reliable and safe and they are consistent in performance at the minimum breaking
dissipation up to and including the breaking capacity rating and at any voltage up to the rated
voltage, when used within the limits of this standard.
During normal use of the fuse resistor with particular overcurrent protection and within the
conditions given in this standard, no permanent arc, nor external arcing, nor any flame that
can endanger the surroundings, shall be produced. During testing and after operation, the
fuse resistor with particular overcurrent protection shall not have suffered damage and the
surroundings shall be unimpaired. Marking shall still be legible.
In general, compliance is checked by carrying out all the tests specified.
5 Standard ratings
The values of rated resistance shall be selected from the E12 or E24 series as given in
IEC 60063.
6 Marking
The requirements of IEC 60127-1:2006, Clause 6, are replaced as follows:
6.1 Each fuse resistor with particular overcurrent protection shall be marked as follows:
a) Rated resistance in ohms (abbreviation Ω or mΩ).
b) The marking of the tolerance on rated resistance shall follow and be adjacent to the
marking of the rated resistance.
c) Rated dissipation in watts (W).
d) Manufacturer's name or trade mark.
e) The symbol “F” shall precede and be adjacent to the marking of the rated resistance.
6.2 Marking shall be indelible and easily legible.
In the case of screen or pad printing, compliance is checked by inspection and by rubbing the
marking by hand for 15 s with a piece of cloth soaked in water and again for 15 s with a piece
of cloth soaked in petroleum spirit.
NOTE 1 For petroleum spirit the use of an aliphatic solvent hexane, with an aromatics content of maximum 0,1 %
volume, a kauri-butanol value of 29, initial boiling point approximately 65 °C, dry-point approximately 69 °C and
specific gravity of approximately 0,68 is recommended.
NOTE 2 For all other printing techniques, the above test is not applicable.
6.3 The marking according to 6.2 shall also be printed on the packing together with a
reference to this standard. The marking of the rated resistance on the packing shall include
the abbreviation Ω or mΩ. In addition, the marking of the rated voltage, rated dissipation P
and minimum breaking dissipation shall be printed on the packing.
Compliance is checked by inspection.
6.4 For colour coding, no test or requirement is specified.
6.5 Where marking is impracticable due to space limitations, the relevant information
should appear on the smallest packing unit and in the manufacturer’s technical literature.
7 General notes on tests
7.1 Atmospheric conditions for testing
See IEC 60127-1:2006, 7.1.
7.2 Type tests
7.2.1 General
The requirements of IEC 60127-1:2006, 7.2, are replaced as follows:
7.2.2 For fuse resistors with particular overcurrent protection designed and rated both for
AC and DC, the number of fuse resistors with particular overcurrent protection required is 45.
For fuse resistors with particular overcurrent protection designed only for AC or DC, the
number of fuse resistors with particular overcurrent protection required is 36.
18 fuse resistors with particular overcurrent protection are kept as spares.
– 12 – IEC 60127-8:2018 © IEC 2018
The fuse resistors with particular overcurrent protection shall be tested or inspected in
accordance with the following subclauses:
a) Marking (see 6.1);
b) Dimensions (see 8.1);
c) Construction (see 8.2);
d) Resistance (see 9.1);
with such additional tests as are specified in Subclauses 7.2.3 to 7.4.
7.2.3 Testing of the minimum and maximum rated resistance of the fuse resistors with
particular overcurrent protection shall then be performed according to the testing schedule
shown in Table 3.
In addition, any one rated resistance value per resistance decade shall be tested.
7.2.4
a) No failure is allowed in any of the tests covered by 8.1.1, 9.1, 9.2 and 9.3.
b) If in the test covered by Clause 6 and those tests described in 8.1 and 8.3, one failure
occurs, the test shall be repeated on twice the number of fuse resistors with particular
overcurrent protection, at the same breaking dissipation and a second failure shall be a
cause for rejection.
If two failures occur, but not both in the same test, the fuse resistors with particular
overcurrent protection shall be deemed to comply provided that there are no further
failures in repeat tests with twice the number of test samples.
If more than two failures occur, the fuse resistors with particular overcurrent protection
shall be deemed not to comply with this standard.
7.3 Fuse-bases for tests
7.3.1 General
The requirements of IEC 60127-1:2006, 7.3, are replaced as follows:
7.3.2 General requirements
The fuse resistors with particular overcurrent protection shall be mounted upon the
appropriate test board (see 7.3.3 or 7.3.4 as appropriate) by soldering.
This test board shall then be mounted on the test fuse-base (Figure 3). The test board shall
be made of epoxide woven glass fabric copper-clad laminated sheet, as defined in
IEC 61249-2-7.
• The nominal sheet thickness shall be 1,6 mm.
• The nominal thickness of copper layer shall be 0,035 mm or 0,070 mm for rated
dissipation values above 5 W.
Metal parts of the fuse-base shall be made of brass with a copper content between 58 % and
70 %. Contact parts shall be silver-plated.
When two or more fuse resistors with particular overcurrent protection are tested in series,
the test fuse-bases shall be located so that there will be a spacing of not less than 50 mm
between any two fuse resistors with particular overcurrent protection. The conductor
connecting the test fuse-bases together, and connecting the test fuse-bases to the ammeter
and the source of supply shall be insulated copper wire. The length of each conductor shall be
250 mm, and the cross-sectional area of the wire shall be approximately 1 mm .
7.3.3 Through-hole mounting of fuse resistors with particular overcurrent protection
For electrical tests, the fuse resistors with particular overcurrent protection shall be mounted
on the test board as shown in Figure 1 in the pair of holes appropriate to the spacing of the
terminations.
7.3.4 Surface mounting of fuse resistors with particular overcurrent protection
For electrical tests, the fuse resistors with particular overcurrent protection shall be mounted
on the test board as shown in Figure 2.
7.4 Nature of supply
See IEC 60127-1:2006, 7.4.
8 Dimensions and construction
8.1 Dimensions
The requirements of IEC 60127-1:2006, 8.1, are replaced as follows:
• The dimensions of the fuse resistors with particular overcurrent protection shall be as
specified by the manufacturer.
• Compliance is checked by measurement of length, width and height.
For through-hole mount fuse resistors with particular overcurrent protection the termination
spacing is checked. In addition, the following applies:
• The termination shall also pass through a 1 mm hole.
• The length of the termination is not specified as this is subject to the method of packaging.
8.1.1 Creepage distances and clearances
The creepage distances and clearances between current-carrying parts (contacts together
with their terminals) and the outside of the enclosure of the fuse resistor with particular
overcurrent protection including insulated metal parts thereof, shall be not less than the
values given in Table 1. The values indicated are absolute minimum values and inclusive of
manufacturing tolerances.
These distances do not apply across the disconnection (between the open contacts) of the
fuse resistors with particular overcurrent protection.
Compliance is checked by measuring the distances concerned.
– 14 – IEC 60127-8:2018 © IEC 2018
Table 1 – Creepage distances and clearances
(absolute minimum values)
Rated voltage, U Clearance Creepage distance
r
V mm mm
0 to 32 0,2 0,53
33 to 50 0,2 1,2
51 to 125 0,5 1,5
126 to 250 1,5 2,5
251 to 400 3,0 4,0
401 to 500 4,0 6,9
NOTE 1 The clearances/creepage distances are specified according to IEC 60664-1.
NOTE 2 The values specified are for typical applications of fuse resistors with particular overcurrent protection
assuming:
a) continuous voltage stress;
b) altitude of 2 000 m;
c) basic insulation;
d) inhomogeneous field;
e) overvoltage category II;
f) pollution degree 2;
g) material group III.
NOTE 3 If conditions are different from those specified in note 2, adjustments in clearances/creepage distances
will be necessary as per IEC 60664-1.
8.2 Construction
The requirements of IEC 60127-1:2006, 8.2, are replaced as follows:
The fuse resistor with particular overcurrent protection shall be completely enclosed.
8.2.1 The fuse resistor with particular overcurrent protection shall be resistant to fire
according to IEC 60695-2-12 and IEC 60695-2-13.
Compliance is checked by inspection. This is not applicable for fuse resistors with particular
overcurrent protection which represent small parts according to IEC 60695-4:2012, 3.78.
For fuse resistor bodies made of plastic material or of material containing organic substances,
the following minimum requirements apply:
• Glow-wire ignition temperature (GWIT) = 775 °C
• Glow-wire flammability index (GWFI) = 850 °C
NOTE 1 For the glow wire tests, the material plates with dimensions according to IEC 60695-2-12:2010, 4.2
and/or IEC 60695-2-13:2010, 4.2, are used.
NOTE 2 For materials such as glass and ceramic whose GWIT and GWFI are thought to be higher than 775 °C
and respectively 850 °C the glow-wire tests do not apply.
8.3 Terminations
The requirements of IEC 60127-1:2006, 8.3, are replaced as follows:
8.3.1 Through-hole mount fuse resistors with particular overcurrent protection
The terminations shall be firmly attached so that it is not possible to remove them without
damaging the fuse resistor with particular overcurrent protection.
Compliance is checked by carrying out the following test.
The tests are carried out in accordance with IEC 60068-2-21.
The following tests shall be applied:
• tensile test Ua , applied force 10 N;
• thrust test Ua , applied force 2 N;
• bending test Ub, applied force 5 N, number of bends: 1.
The sample size is two fuse resistors with particular overcurrent protection for each test. After
testing, the terminations shall remain firmly attached. The resistance shall be measured in
accordance with 9.1, and the change in resistance shall not exceed the value specified by the
manufacturer. Bending test Ub is omitted, if the terminations are less than 5 mm.
The samples are then mounted on the test board as shown in Figure 1.
8.3.2 Surface mount fuse resistors with particular overcurrent protection
The fuse resistors with particular overcurrent protection shall be mounted on the test board as
shown in Figure 2. The test board, with the fuse resistors with particular overcurrent
protection on the underside, shall be placed in the bending jig as shown in Figure 4. The test
board shall then be bent by 1 mm at a rate of 1 mm/s. The test board shall be allowed to
recover from the bent position, and then be removed from the test jig.
After testing, the terminations shall remain firmly attached. The resistance shall be measured
in accordance with 9.1, and the change in resistance shall not exceed the value specified by
the manufacturer.
8.4 Alignment and configuration of terminations
The termination configuration and spacing shall be as specified by the manufacturer.
NOTE 1 Through-hole mounting of fuse resistors with particular overcurrent protection
For through-hole mounting of fuse resistors with particular overcurrent protection, the dimensions specified by the
manufacturer are such as to permit installation on printed circuit boards having a grid system of holes located on
centres of distance e = 2,5 mm. Attention is drawn to the fact that in some parts of the world the value e = 2,54 mm
is still in use by printed circuit designers.
Electrical and electronic circuit designers are advised to apply the requirements of IEC 60326-3 .
NOTE 2 Surface mounting of fuse resistors with particular overcurrent protection
For surface mounting of fuse resistors with particular overcurrent protection, electrical and electronic circuit
designers are advised to design substrate land areas to receive the fuse resistor with particular overcurrent
protection with due consideration for achieving the maximum area of contact in the application, taking into account
the tolerance applied to mechanical placing of the component and the dimensions and tolerances for terminals in
this standard.
8.5 Soldered joints
No test specified.
___________
This standard has been withdrawn.
– 16 – IEC 60127-8:2018 © IEC 2018
8.6 Solderability of terminations
No test specified.
8.7 Resistance to soldering heat
No test specified.
9 Electrical requirements
The requirements of IEC 60127-1:2006, Clause 9, are replaced as follows:
9.1 Resistance value
The samples are drawn at random and numbered consecutively (without being sorted in
descending order of resistance value). The resistance value shall be measured at the points
marked U in Figure 1 for through-hole mount fuse resistors with particular overcurrent
protection and in Figure 2 for surface mount fuse resistors with particular overcurrent
protection, using the test fuse-base shown in Figure 3 (see 7.3).
Resistance values including tolerances as specified by the manufacturer apply.
9.2 Functioning characteristic at the minimum breaking dissipation
9.2.1 Functioning characteristic at an ambient temperature of 70 °C
The breaking dissipation across the fuse resistor with particular overcurrent protection shall
be adjusted to within ± 1 % of the value required in this standard. The breaking dissipation
stability during the test shall be maintained within ± 1 % of the adjusted value.
The accuracy of the measurement of time shall be within a tolerance of ± 5 % for times of less
than 10 s and ± 2 % for times of 10 s or more.
Compliance is checked as follows:
+0
a) The samples are exposed in the test oven to a temperature of 70 until the temperature
−5
has stabilized, shown when two consecutive readings are equal within 1 K.
b) After stabilization of the test oven at 70 °
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