prEN IEC 60269-100:2026

• Status: Not Published
• Publication Date: 23-Feb-2028
• ICS: 29.120.50 - Fuses and other overcurrent protection devices
• Technical Committee: CLC/SR 32B - Low-voltage fuses
• Current Stage: 4020 - Enquiry circulated - Enquiry
• Start Date: 18-Sep-2026
• Due Date: 28-Nov-2025
• Completion Date: 18-Sep-2026
• Directive: 2014/35/EU - Directive 2014/35/EU of the European Parliament and of the Council of 26 February 2014 on the harmonisation of the laws of the Member States relating to the making available on the market of electrical equipment designed for use within certain voltage limits
• Mandate: M/511 - Mandate to CEN, CENELEC and ETSI relating to harmonised standards in the field of the Low Voltage Directive
• Ref Project: oSIST prEN IEC 60269-100:2026 - Low-Voltage Fuses. Part 100: General requirements and tests

prEN IEC 60269-100:2026 is an IEC and CENELEC draft standard for low-voltage fuses. It sets the general requirements and test methods for enclosed current-limiting fuse-links, fuse-holders and complete fuses used in power-frequency AC circuits up to 1 000 V and DC circuits up to 1 500 V. It is the base document for the restructured IEC 60269 series, to be combined with one 200-series part for the utilization class and one 300-series part for the fuse system.

What does prEN IEC 60269-100:2026 specify?

prEN IEC 60269-100:2026 specifies the common rules for low-voltage fuses: their ratings, constructional conditions, markings and type tests. The document is aimed at making fuse-links and fuse parts interchangeable where their dimensions and characteristics are compatible.

The scope covers enclosed current-limiting fuse-links with rated breaking capacities of not less than 6 kA for AC or DC circuits within the stated voltage limits. It excludes miniature fuses covered by IEC 60127. The same requirements also apply to fuse-links used in fuse-combination units according to IEC 60947-3.

The document is organized into clauses for scope, normative references, terms and definitions, service conditions, classification, characteristics, markings, construction, and type tests.

Annex	What it covers
Annex A	Planned documents in the restructured IEC 60269-200 and -300 series
Annex B	Methods for measuring short-circuit power factor
Annex C	Calculation of pre-arcing I²t and operating I²t at reduced voltage
Annex D	Effect of ambient temperature and surroundings on fuse-link performance
Annex E	Special test for cable overload protection
Annex F	Survey of complete tests across the 200 and 300 series
Annex G	Components of a fuse and their arrangement

What are the key requirements of prEN IEC 60269-100:2026?

prEN IEC 60269-100:2026 sets the shared performance base for fuse systems, and the main requirements are in Clauses 4 to 9. In practice, these clauses tell the user what environment the fuse is designed for, which ratings must be stated, how the fuse must be built, and which tests prove the design.

Service conditions and application limits

Clause 4 defines the normal service conditions under which the fuse is deemed to operate satisfactorily. The reference conditions include ambient air temperature, altitude, atmospheric cleanliness, humidity, voltage and current limits, and installation conditions.

This matters because the standard ratings and test results assume those conditions unless a subsequent part says otherwise. If a fuse is used outside the stated temperature or altitude range, the manufacturer has to provide the relevant information or the applicable subsequent part has to add the needed requirements.

Ratings and characteristics

Clause 6 requires rated voltage, rated current, rated frequency where applicable, power dissipation and maximum power acceptance to be defined. It also covers time-current characteristics, breaking capacity, cut-off current and I²t characteristics.

This is the core of fuse selection in practice. A buyer or engineer needs these values to match the fuse to the circuit voltage, the expected load current, the available short-circuit current and the desired protective behavior.

Clause 6 also distinguishes breaking ranges and utilization classes, including "g" fuse-links for full-range breaking capacity and "a" fuse-links for partial-range breaking capacity. That distinction matters because "a" fuse-links are generally used with another device for overload protection, while "g" fuse-links can clear a wider range of overcurrents on their own.

Marking and product identification

Clause 7 requires durable, legible markings and gives separate marking expectations for fuse-holders and fuse-links. The markings include manufacturer identification, voltage and current ratings, current type where applicable, utilization class for fuse-links, system and size, and the IEC 60269 designation.

This matters for installation and maintenance because the marking is the main way to confirm compatibility. For small fuse-links, the clause allows a reduced marking set when full marking is impracticable, with the rest of the information placed in product documentation.

Constructional and safety conditions

Clause 8 sets the standard conditions for construction, including mechanical design, clearances, creepage distances, impulse withstand, leakage current, temperature rise, breaking capacity, protection against electric shock, corrosion resistance, abnormal heat and fire, and electromagnetic compatibility.

In practice, these requirements protect users, terminals and nearby equipment. For example, the standard specifies temperature-rise limits for terminals, and it requires the fuse-holder to be able to carry the fuse-link current without exceeding those limits under standard service conditions.

Type tests and acceptance

Clause 9 describes the type tests used to verify the characteristics in Clauses 6 and 8. The tests cover insulation, suitability for isolation, temperature rise, operation, breaking capacity, cut-off current, I²t characteristics, enclosure protection, heat resistance, contact endurance, mechanical strength, corrosion-related checks and marking durability.

For manufacturers and certification bodies, this clause is the basis for design validation and product qualification. For users, it shows which performances are proven by test rather than only declared.

What terms does prEN IEC 60269-100:2026 define?

• Fuse - A device that opens a circuit by fusing one or more designed components when current exceeds a given value for long enough.
• Fuse-holder - The combination of the fuse-base and fuse-carrier that supports the fuse-link and provides the connection interface.
• Fuse-link - The replaceable part of a fuse that contains the fuse-element(s) and operates when overcurrent persists.
• Current-limiting fuse-link - A fuse-link that limits the current to a substantially lower value than the prospective peak current during operation.
• Breaking capacity - The prospective current value a fuse-link can interrupt at a stated voltage under specified conditions.
• "g" fuse-link - A full-range breaking-capacity fuse-link that can break all currents that melt its element up to rated breaking capacity.
• "a" fuse-link - A partial-range breaking-capacity fuse-link used mainly for short-circuit protection.
• I²t characteristic - The curve or values describing the Joule integral of a fuse during pre-arcing and/or operating time.

Who uses prEN IEC 60269-100:2026?

prEN IEC 60269-100:2026 is used by fuse manufacturers, test laboratories, certification bodies, specifiers, installers and quality managers. It is also relevant to buyers who need to compare fuse products on the basis of common technical rules.

The document is used for product design, type testing, marking, selection of compatible fuse-links and fuse-holders, and checking installation suitability. It is especially relevant in electrical power distribution, switchgear, fuse-combination units and other low-voltage equipment using AC or DC protection within the stated voltage range.

What changed in prEN IEC 60269-100:2026 from the previous edition?

prEN IEC 60269-100:2026 reissues IEC 60269-1:2024 in a restructured form as part 100 of the IEC 60269 series. The foreword states that technical changes were kept to a minimum, but some minor changes, corrections and clarifications were made during the restructuring. The new structure separates the general requirements in part 100 from the supplementary and modified requirements in the 200 and 300 series.

Which standards are used with prEN IEC 60269-100:2026?

• IEC 60050-441, IEC 60050-442, IEC 60050-482, IEC 60050-521, IEC 60050-551, IEC 60050-651 and IEC 60050-826 - provide the vocabulary used for devices, accessories, batteries, semiconductor devices, power electronics, live working and electrical installations.
• IEC 60364-5-51 - supports the voltage-related installation rules for electrical equipment.
• IEC 60529 - supplies the IP code basis used when fuse enclosures are checked.
• IEC 60664-1 - provides insulation coordination principles, requirements and tests.
• IEC 60695-2-10 and IEC 60695-2-11 - provide the glow-wire fire test methods used for fire-related verification.
• IEC 60947-3 - covers fuse-combination units and is named for fuse-links used in those units.
• IEC 61140 - provides common aspects of protection against electric shock.
• ISO 3 - gives the preferred number series used for intermediate rated voltages.
• IEC TR 60269-5 - gives guidance for applying low-voltage fuses, including de-rating for higher altitude.
• IEC 60269-200 series and IEC 60269-300 series - provide the supplementary and modified requirements that complete the restructured fuse series.

What does the prEN IEC 60269-100:2026 document contain?

prEN IEC 60269-100:2026 contains the main test and reference machinery for the series, including figures for cut-off characteristics, isolation marking, overload behavior, breaking-capacity circuits and oscillogram interpretation. It also includes tables for preferred voltages, conventional times, clearances, creepage distances, impulse withstand voltage, temperature-rise limits, arc-voltage limits and breaking-capacity test conditions.

The annexes add the working tools that users often need in practice: power-factor measurement methods, I²t calculation formulas, a cable-overload protection test, and a survey of the complete tests used across the series. Annex G gives a simple component map of a fuse, which helps readers relate the terminology in the clauses to the physical parts of the device.

SLOVENSKI STANDARD
01-november-2026
Nizkonapetostne varovalke. 100.del: Splošne zahteve in preskusi
Low-Voltage Fuses. Part 100: General requirements and tests
Ta slovenski standard je istoveten z: prEN IEC 60269-100:2026
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.

32B/791/CDV
COMMITTEE DRAFT FOR VOTE (CDV)
PROJECT NUMBER:
IEC 60269-100 ED1
DATE OF CIRCULATION: CLOSING DATE FOR VOTING:
2026-09-18 2026-12-11
SUPERSEDES DOCUMENTS:
32B/777/CD, 32B/783/CC
IEC SC 32B : LOW-VOLTAGE FUSES
SECRETARIAT: SECRETARY:
Germany Mr Andreas Schüppel
OF INTEREST TO THE FOLLOWING COMMITTEES: HORIZONTAL FUNCTION(S):
SC 23E,SC 37A,TC 64,SC 121A,SC 121B
ASPECTS CONCERNED:
Electricity transmission and distribution,Energy Efficiency
SUBMITTED FOR CENELEC PARALLEL VOTING NOT SUBMITTED FOR CENELEC PARALLEL VOTING
Attention IEC-CENELEC parallel voting
The attention of IEC National Committees, members of
CENELEC, is drawn to the fact that this Committee Draft
for Vote (CDV) is submitted for parallel voting.
The CENELEC members are invited to vote through the
CENELEC online voting system.
This document is still under study and subject to change. It should not be used for reference purposes.
Recipients of this document are invited to submit, with their comments, notification of any relevant patent rights of
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Recipients of this document are invited to submit, with their comments, notification of any relevant “In Some
Countries” clauses to be included should this proposal proceed. Recipients are reminded that the CDV stage is
the final stage for submitting ISC clauses. (SEE AC/22/2007 OR NEW GUIDANCE DOC).

TITLE:
Low-Voltage Fuses. Part 100: General requirements and tests

PROPOSED STABILITY DATE: 2030
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IEC CDV 60269-100 © IEC 2026
CONTENTS
CONTENTS . 1
FOREWORD . 6
Introduction. 8
1 Scope . 9
2 Normative references . 9
3 Terms and definitions . 10
3.1 Fuses and their component parts . 11
3.2 General terms . 13
3.3 Characteristic quantities . 16
3.4 Application related terms . 21
3.4.1 Semiconductor protection . 21
3.4.2 PV systems . 22
3.4.3 Battery protection . 22
4 Conditions for operation in service . 22
4.1 General . 22
4.2 Ambient air temperature (T ) . 22
a
4.3 Altitude . 22
4.4 Atmospheric conditions . 22
4.5 Voltage . 23
4.6 Current . 23
4.7 Frequency, power factor and time constant . 23
4.7.1 Frequency . 23
4.7.2 Power factor . 23
4.7.3 Time constants . 23
4.8 Conditions of installation . 23
4.8.1 General . 23
4.8.2 Utilization class . 24
4.8.3 Selectivity . 24
4.8.4 Selection of a fuse-link . 24
5 Classification . 24
6 Characteristics of fuses . 24
6.1 Summary of characteristics . 24
6.1.1 General . 24
6.1.2 Fuse-holders . 24
6.1.3 Fuse-links . 24
6.1.4 Complete fuses. 25
6.2 Rated voltage . 25
6.3 Rated current . 25
6.3.1 Rated current of the fuse-link . 25
6.3.2 Rated current of the fuse-holder . 25
6.3.3 Peak withstand current of a fuse-holder . 26
6.4 Rated frequency . 26
6.5 Rated power dissipation of a fuse-link and rated maximum power
acceptance of a fuse-holder . 26
6.6 Limits of time-current characteristics . 26
6.6.1 General . 26
IEC CDV 60269-100 © IEC 2026
6.6.2 Time-current characteristics, time-current zones . 26
6.6.3 Conventional times and currents . 27
6.6.4 Gates . 27
6.7 Utilization class and rated breaking capacity . 27
6.7.1 General . 27
6.7.2 Identification of the breaking range . 27
6.7.3 Application category . 27
6.7.4 Rated breaking capacity . 27
6.8 Cut-off current and I t characteristics . 28
6.8.1 General . 28
6.8.2 Cut-off current characteristics . 28
6.8.3 I t characteristics . 28
7 Markings . 29
7.1 General . 29
7.2 Markings of fuse-holders . 29
7.3 Markings of fuse-links . 29
8 Standard conditions for construction . 30
8.1 Mechanical design . 30
8.1.1 Replacement of fuse-links. 30
8.1.2 Connections, including terminals . 30
8.1.3 Fuse-contacts . 30
8.1.4 Construction of a gauge-piece . 31
8.1.5 Mechanical strength of the fuse-link . 31
8.2 Insulating properties and suitability for isolation . 31
8.2.1 General . 31
8.2.2 Clearances and creepage distances . 31
8.2.3 Rated impulse withstand voltage . 32
8.2.4 Leakage currents of fuses. 33
8.2.5 Additional constructional requirements for fuses with linked fuse-
carriers . 33
8.3 Temperature rise, power dissipation of the fuse-link and maximum power
acceptance of a fuse-holder . 33
8.4 Operation . 34
8.5 Breaking capacity . 35
8.6 Cut-off current characteristic . 35
8.7 I t characteristics . 35
8.8 Overcurrent selectivity of fuse-links . 36
8.9 Protection against electric shock . 36
8.9.1 General . 36
8.9.2 Requirements for fuses to be used by authorized persons only . 36
8.9.3 Additional requirements for fuses to be used by ordinary persons . 37
8.10 Resistance to heat . 37
8.11 Mechanical strength . 38
8.12 Resistance to corrosion . 38
8.12.1 General . 38
8.12.2 Resistance to rusting . 38
8.12.3 Resistance to season cracking . 38
8.13 Resistance to abnormal heat, and fire . 38
IEC CDV 60269-100 © IEC 2026
8.14 Electromagnetic compatibility . 38
9 Type Tests . 38
9.1 General requirements for Type Tests . 38
9.1.1 General . 38
9.1.2 Ambient air temperature (T ) . 39
a
9.1.3 Condition of the fuse. 39
9.1.4 Arrangement of the fuse and dimensions . 39
9.1.5 Testing of fuse-links . 39
9.1.6 Testing of fuse-holders . 39
9.1.7 Complete tests . 40
9.1.8 Testing of fuse-links of a homogeneous series . 40
9.2 Verification of the insulating properties and of the suitability for isolation . 40
9.2.1 Arrangement of the fuse-holder . 40
9.2.2 Verification of the insulating properties . 41
9.2.3 Verification of the suitability for isolation . 42
9.2.4 Acceptability of test results . 43
9.3 Verification of temperature rise and power dissipation . 43
9.3.1 Arrangement of the fuse . 43
9.3.2 Measurement of the temperature rise . 43
9.3.3 Measurement of the power dissipation of the fuse-link . 43
9.3.4 Temperature rise of the fuse-holder . 44
9.3.5 Test method . 45
9.3.6 Acceptability of test results . 45
9.4 Verification of operation . 45
9.4.1 Arrangement of the fuse . 45
9.4.2 Ambient air temperature . 45
9.4.3 Test method and acceptability of test results . 45
9.5 Verification of the breaking capacity. 49
9.5.1 General . 49
9.5.2 Arrangement of the fuse . 49
9.5.3 Characteristics of the test circuit . 49
9.5.4 Measuring instruments . 51
9.5.5 Calibration of test circuit . 51
9.5.6 Test method . 53
9.5.7 Interpretation of oscillograms . 54
9.5.8 Acceptability of test results . 57
9.6 Verification of the cut-off current characteristics. 57
9.6.1 Test method . 57
9.6.2 Acceptability of test results . 57
9.7 Verification of I t characteristics and overcurrent selectivity . 57
9.7.1 Test method . 57
9.7.2 Acceptability of test results . 58
9.7.3 Verification of overcurrent selectivity . 58
9.8 Verification of the degree of protection of enclosures . 58
9.9 Verification of resistance to heat . 58
9.10 Verification of non-deterioration of contacts . 58
9.10.1 Arrangement of the fuse . 58
9.10.2 Test method . 58
IEC CDV 60269-100 © IEC 2026
9.10.3 Acceptability of test results . 59
9.11 Mechanical and miscellaneous tests . 59
9.11.1 Mechanical strength . 59
9.11.2 Verification of freedom from season cracking. 59
9.11.3 Verification of resistance of insulating materials to abnormal heat, and
fire . 60
9.11.4 Verification of resistance to rusting . 60
9.12 Test of durability of markings . 60
Annex A (informative) List of planned documents within IEC 60269-200 and -300
series . 61
Annex B (normative) Measurement of short-circuit power factor . 63
Annex C (normative) Calculation of pre-arcing I t values and calculation of operating
I t values at reduced voltage . 66
C.1 Approximation of the pre-arcing I2t value at 0,01 s . 66
C.2 Calculation of the value of pre-arcing I²t under the conditions of test no. 2 . 66
C.3 Calculation of the value of operating I²t at reduced voltage . 66
Annex D (informative) Effect of change of ambient temperature and surroundings on
the performance of fuse-links . 68
D.1 Effect of increase of ambient temperature . 68
D.1.1 Effect on current rating . 68
D.1.2 Effect on temperature rise . 68
D.1.3 Effect on conventional fusing and non-fusing current (I and I ) . 68
f nf
D.1.4 Effects on motor starting conditions . 68
D.2 Effects caused by a decrease in ambient air temperature . 68
D.3 Influences of installation conditions . 68
Annex E (normative) Special test for cable overload protection . 69
E.1 General . 69
E.2 Arrangement of the fuse. 69
E.2.1 Special test for fuses according to IEC 60269-301 (NH system) for
cable overload protection . 69
E.2.2 Special test for fuses according to IEC 60269-302 (D) for cable
overload protection . 69
E.3 Test method and acceptability of test results . 70
Annex F (normative) Survey of complete tests . 71
Annex G (informative) Components of a fuse . 72
Bibliography . 74

Figure 1 – General presentation of the cut-off characteristics for a series of AC fuse-
links 28
Figure 2 – Symbol for marking fuse-holders suitable for isolation . 33
Figure 3 – Overload curve and time-current characteristic for "a" fuse-links . 47
Figure 4 – Typical diagram of the circuit used for breaking capacity test . 50
Figure 5 – Interpretation of oscillograms taken during the AC breaking-capacity tests
(see 9.5.7) . 55
Figure 6 – Interpretation of oscillograms taken during the DC breaking-capacity tests
(see 9.5.7) . 56
Figure B.1 – Determination of circuit-impedance for calculation of power factor in
accordance with method I . 65
IEC CDV 60269-100 © IEC 2026
Figure G.1 – Characteristic parts of fuses . 73

Table 1 – Maximum values of applied voltage . 23
Table 2 – preferred values of rated voltages . 25
Table 3 – Conventional times . 27
Table 4 – Minimum clearances in air . 31
Table 5 – Minimum creepage distances . 32
Table 6 – rated impulse withstand voltage . 32
Table 7 – Temperature rise limits Δ𝑇 = (𝑇 − 𝑇𝑎) for terminals . 34
Table 8 – Maximum arc voltage . 35
Table 9 – Test voltages. 41
Table 10 – Test voltages across the open contacts of fuses suitable for isolation . 42
Table 11 – Cross-sectional area of copper conductors for tests according to 9.3 and
9.4 44
Table 12 – Conventional cable overload protection test parameters . 48
Table 13 – Values for breaking-capacity tests on AC fuses . 51
Table 14 – Values for breaking capacity tests on DC fuses . 52
Table A.1 – Subsequent parts of IEC 60269-200 series (planned). 61
Table A.2 – Subsequent parts of IEC 60269-300 series (planned). 62

IEC CDV 60269-100 © IEC 2026
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
Low-Voltage Fuses. Part 100: General requirements and tests

FOREWORD
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced
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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,
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IEC CDV 60269-100 © IEC 2026
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 60269-100 has been prepared by subcommittee 32B: Low-voltage fuses, of IEC technical
committee 32: Fuses. It is an International Standard.
IEC 60269-1:2024 [1] has been restructured and reissued as IEC 60269-100 and subsequent
parts of 200 and 300 series. The documents IEC 60269-1:2024 [1] and its subsequent parts 2
to 7 cannot be used in conjunction with IEC 60269-100 and its subsequent parts of IEC 60269-
200 series (all parts) and IEC 60269-300 series (all parts), except part 5, which is an
independent guide, currently covering both series of standards.
The restructured IEC 60269 series consist of the following parts, under the general title Low-
voltage fuses:
– IEC 60269-100: General Rules
– IEC 60269-200 series (all parts): Supplementary and modified requirements for utilization
classes
– IEC 60269-300 series (all parts): Supplementary and modified requirements for fuse
systems
– IEC TR 60269-5:2014/AMD1:2020 [2]: Guidance for the application of low-voltage fuses
A comprehensive list of all parts in the IEC 60269 series, published under the general title Low-
voltage fuses, can be found on the IEC website.
The text of this International Standard is based on the following documents:
Draft Report on voting
XX/XX/FDIS XX/XX/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.
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.
IEC CDV 60269-100 © IEC 2026
Introduction
The IEC 60269 series is a series of International Standards with a very long history. Over the
decades, the structure and the content of its documents has changed and evolved, leading to
a mixture of fuse characteristics (e.g. "gG") and fuse systems defining geometries and specific
requirements.
Based on the developments in the last decades, the IEC 60269 series in its current form is not
easy to apply to new products, nor is it easy to maintain. Therefore, IEC Subcommittee 32B has
decided to start a complete restructuring of the series with the following targets:
– IEC 60269-1 was not "general", it contains requirements for the characteristics "gG" and
"aM" besides other general requirements and tests for fuses; after the restructuring phase,
the new part 100 (this document) contains general requirements and tests only
– other parts of the old IEC 60269 series also contain requirements, that are needed in more
than one subsequent parts; These parts are moved to part 100, as soon as it is needed for
at least two subsequent parts, to avoid duplicated text in subsequent parts
– describe a specific fuse system (e.g. "cylindrical fuses") in one single document, not in every
single document it can be used for
– describe a specific characteristic (e.g. "gG", which is currently defined in three subsequent
parts) in one single document
– to simplify the maintenance of the standard series by reducing the need to maintain only
one document in case of necessary changes
– to enhance and simplify the development of new fuses (e.g. new characteristics) or new
combinations of fuse system and characteristic by the ability to combine these documents
in new ways
– To align the IEC US systems with the UL series of standards
– Clear and identical structure throughout the whole series of standards
– Harmonisation of requirements and tests defined in the different subsequent parts (as far
as possible)
This document defines general requirements and tests for fuses, and it is the first part to be
released within the new series. Annex A in this document provides a comprehensive list of
documents planned to represent the new structure.
At this first stage of the restructuring project, it was agreed that the technical changes should
be kept to a minimum, so that the adaptation to the new series is as easy as possible. Some
minor changes had to be made though, since the thorough rework of the documents and the
collection of requirements unveiled some errors and/or misunderstandings that have been
corrected or clarified.
The newly structured IEC 60269 series is applied as a combination of three documents: part
100 (this document) defining the general requirements, one part of 200 series to define
supplementary or modified requirements for a specific utilization class, and one part of 300
series to define supplementary or modified requirements for a specific fuse system. Single
documents are not intended to be used alone.
IEC CDV 60269-100 © IEC 2026
1 Scope
This part of IEC 60269 series is applicable to fuses incorporating enclosed current-limiting fuse-
links with rated breaking capacities of not less than 6 kA, intended for protecting power -
frequency AC circuits of rated voltages not exceeding 1 000 V or DC circuits of rated voltages
not exceeding 1 500 V.
Subsequent parts of this document cover supplementary or modified requirements for such
fuses intended for specific conditions of use or applications.
NOTE 1 Modifications of, and supplements to this document that apply for specific types of fuses for particular
applications - for example, certain fuses for rolling stock, automotive applications or fuses for high-frequency circuits
- are covered by separate standards.
NOTE 2 See Annex A for a list of (planned) subsequent parts of this document.
This standard does not apply to miniature fuses as covered by IEC 60127 [3] series.
The requirements defined in this document and its subsequent parts are also applicable to fuse-
links intended to be used in fuse-combination units according to IEC 60947-3 [4].
The object of this standard is to establish the characteristics of fuses or parts of fuses ( fuse-
base , fuse-carrier , fuse-link ) in such a way that they can be replaced by other fuses or parts
of fuses having the same characteristics provided, that they are interchangeable as far as their
dimensions are concerned. For this purpose, this standard and its subsequent parts refer to
– the following characteristics of fuses:
• their rated values
• their dielectric properties
• their temperature rise in normal service
• the power dissipation of the fuse-link and the maximum power acceptance of a fuse-
holder.
• their time-current characteristics
• their breaking capacity
• their cut-off current characteristics and their I t characteristics.
– type test for verification of the characteristics of fuses
– the marking of fuses.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies.
For undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 60050-151:2001, International Electrotechnical Vocabulary (IEV) - Part 151: Electrical and
magnetic devices
IEC 60050-428:2024, International Electrotechnical Vocabulary (IEV) - Part 428: Safety of
machinery
IEC 60050-441:1984, International Electrotechnical Vocabulary (IEV) - Part 441: Switchgear,
controlgear and fuses
IEC CDV 60269-100 © IEC 2026
IEC 60050-442:1998, International Electrotechnical Vocabulary (IEV) - Part 442: Electrical
accessories
IEC 60050-482:2004, International Electrotechnical Vocabulary (IEV) - Part 482: Primary and
secondary cells and batteries
IEC 60050-521:2002, International Electrotechnical Vocabulary (IEV) - Part 521:
Semiconductor devices and integrated circuits
IEC 60050-551:1998, International Electrotechnical Vocabulary (IEV) - Part 551: Power
electronics
IEC 60050-651:2014, International Electrotechnical Vocabulary (IEV) - Part 651: Live working
IEC 60050-826:2022, International Electrotechnical Vocabulary (IEV) - Part 826: Electrical
installations
IEC 60364-5-51:2005, Electrical installations of buildings - Part 5-51: Selection and erection of
electrical equipment - Common rules
IEC 60529:1989/AMD2:2013,
IEC 60664-1:2020, Insulation coordination for equipment within low-voltage supply systems -
Part 1: Principles, requirements and tests
IEC 60664-1:2020/AMD1:2025, Amendment 1 - Insulation coordination for equipment within
low-voltage supply systems - Part 1: Principles, requirements and tests
IEC 60695-2-10:2021, Fire hazard testing - Part 2-10: Glowing/hot-wire based test methods -
Glow-wire apparatus and common test procedure
IEC 60695-2-11:2021, Fire hazard testing - Part 2-11: Glowing/hot-wire based test methods -
Glow-wire flammability test method for end products (GWEPT)
IEC 60947-3:2020/AMD1:2025, Amendment 1 - Low-voltage switchgear and controlgear - Part
3: Switches, disconnectors, switch-disconnectors and fuse-combination units
IEC 61140:2016, Protection against electric shock - Common aspects for installation and
equipment
ISO 3:1973, Preferred numbers — Series of preferred numbers
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following
addresses:
– IEC Electropedia: available at https://www.electropedia.org/
– ISO Online browsing platform: available at https://www.iso.org/obp
IEC CDV 60269-100 © IEC 2026
3.1 Fuses and their component parts
3.1.1
fuse
device that by the fusing of one or more of its specially designed and proportioned components
opens the circuit in which it is inserted by breaking the current when this exceeds a given value
for a sufficient time
Note 1 to entry: The fuse comprises all the parts that form the complete device.
Note 2 to entry: Annex G of this document shows a general drawing of a fuse and its parts.
[SOURCE: IEC 60050-441:1984 Chapter 441-18-01]
3.1.2
fuse-holder
combination of the fuse-base (3.1.2.1) with its fuse-carrier (3.1.2.2)
Note 1 to entry: Where, in this standard and its subsequent parts, the term fuse-holder (3.1.2) is used, it covers
both fuse-base (3.1.2.1) and/or fuse-carrier (3.1.2.2), if no clearer distinction is necessary.
[SOURCE: IEC 60050-441:1984 Chapter 441-18-14, modified (added note to entry)]
3.1.2.1
fuse-base
fuse-mount
fixed part of a fuse (3.1.1) provided with contacts and terminals
Note 1 to entry: Where applicable, covers are considered as part of the fuse-base (3.1.2.1).
[SOURCE: IEC 60050-441:1984 Chapter 441-18-02, modified (added note to entry)]]
3.1.2.2
fuse-carrier
movable part of a fuse (3.1.1) designed to carry a fuse-link (3.1.3)
[SOURCE: IEC 60050-441:1984 Chapter 441-18-13]
3.1.3
fuse-link
fuse-links
part of a fuse (3.1.1) including the fuse-element (3.1.5)(s), intended to be replaced after the
fuse (3.1.1) has operated
[SOURCE: IEC 60050-441:1984 Chapter 441-18-09 modified (brackets removed)]
3.1.4
fuse-contact
two or more conductive parts designed to ensure circuit continuity between a fuse-link (3.1.3)
and the corresponding fuse-holder (3.1.2)
Note 1 to entry: a fuse-contact (3.1.4) can either be a fuse-base contact according to IEC 60050-441:1984 Chapter
441-18-03, or a fuse-link contact according to IEC 60050-441:1984 chapter 441-15-04, or a fuse-carrier contact
according to IEC 60050-441:1984 Chapter 441-18-05.
3.1.5
fuse-element
part of the fuse-link (3.1.3) designed to melt under the action of current exceeding some definite
value for a definite period
Note 1 to entry: The fuse-link (3.1.3) may comprise several fuse-elements in parallel.
IEC CDV 60269-100 © IEC 2026
[SOURCE: IEC 60050-441:1984 Chapter 441-18-08, modified (added note to entry)]
3.1.6
indicating device
indicator
part of a fuse (3.1.1) provided to indicate whether the fuse-link (3.1.3) has operated
[SOURCE: IEC 60050-441:1984 Chapter 441-18-17]
3.1.7
striker
mechanical device forming part of a fuse-link (3.1.3) which, when the fuse-link (3.1.3) operates,
releases the energy required to cause operation of other apparatus or indicators or to provide
interlocking
[SOURCE: IEC 60050-441:1984 Chapter 441-18-18]
3.1.8
signalling device
fuse monitoring
device forming part of the fuse and signalling the fuse operation to a remote p
...