IEC 60127-4:2005

IEC 60127-4 ®
Edition 3.2 2012-12
CONSOLIDATED VERSION
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Miniature fuses –
Part 4: Universal modular fuse-links (UMF) – Through-hole and surface mount
types
Coupe-circuit miniatures –
Partie 4: Eléments de remplacement modulaires universels (UMF) – Types de
montage en surface et montage par trous

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IEC 60127-4 ®
Edition 3.2 2012-12
CONSOLIDATED VERSION
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Miniature fuses –
Part 4: Universal modular fuse-links (UMF) – Through-hole and surface mount

types
Coupe-circuit miniatures –
Partie 4: Eléments de remplacement modulaires universels (UMF) – Types de

montage en surface et montage par trous

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.120.50 ISBN 978-2-8322-0554-9

– 2 – 60127-4  IEC:2005+A1:2008+A2:2012
CONTENTS
FOREWORD . 3
INTRODUCTION . 5

1 Scope and object . 6
2 Normative references. 6
3 Terms and definitions . 7
4 General requirements . 7
5 Standard ratings . 7
6 Marking . 8
7 General notes on tests . 8
8 Dimensions and construction . 9
9 Electrical requirements . 12
10 Standard sheets . 24

Annex A (informative) Mounting for surface mount fuse-links . 28

Bibliography . 31

Figure 1 – Unique identifying symbol for UMFs . 19
Figure 2 – Test board for through-hole fuse-links . 19
Figure 3 − Test board for surface mount fuse-links . 20
Figure 4 – Test fuse base . 21
Figure 5 – Bending jig for surface mount fuse-links . 22
Figure 6 – Test circuits for breaking capacity tests . 23
Figure A.1 – Parameters for reflow temperature . 29

Table 1 – Maximum values of voltage drop and sustained dissipation . 15
Table 2 − Testing schedule for individual ampere ratings . 16
Table 3 – Testing schedule for maximum ampere rating of a homogeneous series . 17
Table 4 – Testing schedule for minimum ampere rating of a homogeneous series . 18

60127-4  IEC:2005+A1:2008+A2:2012 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
_________
MINIATURE FUSES –
Part 4: Universal modular fuse-links (UMF) –
Through-hole and surface mount types
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,
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Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
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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
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3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
This consolidated version of the official IEC Standard and its amendments has been prepared
for user convenience.
IEC 60127-4 edition 3.2 contains the third edition (2005) [documents 32C/362/FDIS and 32C/366/
RVD], its amendment 1 (2008) [documents 32C/411/FDIS and 32C/412/RVD] and its amendment
2 (2012) [documents 32C/456/CDV and 32C/463/RVC].
A vertical line in the margin shows where the base publication has been modified by
amendments 1 and 2. Additions and deletions are displayed in red, with deletions being struck
through.
– 4 – 60127-4  IEC:2005+A1:2008+A2:2012
International Standard IEC 60127-4 has been prepared by subcommittee 32C: Miniature fuses,
of IEC technical committee 32: Fuses.
The major technical changes with regard to the previous edition are as follows: introduction of
physically smaller devices with lower rated voltages. Fuse-link temperature test (9.7) is
modified.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
The clauses of this standard supplement, modify or replace the corresponding clauses in
IEC 60127-1.
Where there is no corresponding clause or subclause in this standard, the clause or subclause
of IEC 60127-1 applies without modification as far as is reasonable. When this standard states
“addition”, “modification” or “replacement”, the relevant text in IEC 60127-1 is to be adapted
accordingly.
The IEC 60127 series is subdivided as follows:
Part 1: Definitions for miniature fuses and general requirements for miniature fuse-links
Part 2: Cartridge fuse-links
Part 3: Sub-miniature fuse-links
Part 4: Universal modular fuse-links (UMF)
Part 5: Guidelines for quality assessment of miniature fuse-links
Part 6: Fuse-holders for miniature fuse-links
Part 7: (Free for further documents)
Part 8: (Free for further documents)
Part 9: (Free for further documents)
Part 10: User guide for miniature fuses

The committee has decided that the contents of the base publication and its amendments will
remain unchanged until the stability date indicated on the IEC web site under
"http://webstore.iec.ch" in the data related to the specific publication. At this date, the
publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
The “colour inside” logo on the cover page of this publication indicates
IMPORTANT –
that it contains colours which are considered to be useful for the correct understanding
of its contents. Users should therefore print this publication using a colour printer.

60127-4  IEC:2005+A1:2008+A2:2012 – 5 –
INTRODUCTION
The trend towards miniaturization of electronic equipment has caused users to require fuse-
links of small dimensions, and of appropriate design for application to printed circuit boards or
other substrate systems, possibly by automatic means. These fuse-links should be designed to
incorporate a degree of non-interchangeability.
Rated voltages of 12,5 V, 25 V, 32 V, 50 V, 63 V, 125 V, and 250 V are specified together with
the following characteristics: very quick acting (FF), quick acting (F), time-lag (T) and long
time-lag (TT).
Because of the increasing importance of limitation of transient overvoltages in new technology,
recommendations are included for limits to the overvoltages produced by these fuses under
specified test conditions related to typical circuit configurations.
The option is given to specify the breaking capacity with alternating current or direct current;
it is considered that fuses that meet the d.c. requirement will meet the a.c. requirement;
however, testing is required to validate this. Fuses may be dual rated, in which case the
manufacturer's literature should be referred to.
The users of miniature fuses express the wish that all standards, recommendations and other
documents relating to miniature fuses should have the same publication number in order to
facilitate reference to fuses in other specifications, for example, equipment specifications.
Furthermore, a single publication number and subdivision into parts would facilitate the
establishment of new standards, because clauses and subclauses containing general require-
ments need not be repeated.
– 6 – 60127-4  IEC:2005+A1:2008+A2:2012
MINIATURE FUSES –
Part 4: Universal modular fuse-links (UMF) –
Through-hole and surface mount types

1 Scope and object
This part of IEC 60127 relates to universal modular fuse-links (UMF) 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-links for appliances intended to be used under special conditions,
such as in a corrosive or explosive atmosphere.
These fuses are normally intended to be mounted or replaced only by appropriately skilled
persons using specialized equipment.
Fuse-links for use in fuse-holders are under consideration.
This standard applies in addition to the requirements of IEC 60127-1.
The objectives of this part of IEC 60127 are as given in IEC 60127-1, with the additional
requirement of a degree of non-interchangeability.
2 Normative references
The following referenced documents are indispensable for the application of this document. For
dated references, only the edition cited applies. For undated references, the latest edition of
the referenced document (including any amendments) applies.
IEC 60068-2-20:1979, Basic environmental testing procedures – Part 2: Tests – Test T:
Soldering
Amendment 2 (1987)
IEC 60068-2-20:2008, Environmental testing – Part 2-20: Tests – Test T: Test methods for
solderability and resistance to soldering heat of devices with leads
IEC 60068-2-21:1999, Environmental testing – Part 2-21: Tests – Test U: Robustness of
terminations and integral mounting devices
IEC 60068-2-58:2004, Environmental testing – Part 2-58: Tests – Test Td: Test methods for
solderability, resistance to dissolution of metallization and to soldering heat of surface
mounting devices (SMD)
IEC 60127-1:1988, Miniature fuses – Part 1: Definitions for miniature fuses and general
requirements for miniature fuse-links
Amendment 1 (1999)
Amendment 2 (2002)
IEC 60194:1999, Printed board design, manufacture and assembly – Terms and definitions
___________
There exists a consolidated version (2003).

60127-4  IEC:2005+A1:2008+A2:2012 – 7 –
IEC 60664-1:1992, Insulation coordination for equipment within low-voltage systems – Part 1:
Principles, requirements and tests
Amendment 1 (2000)
Amendment 2 (2002)
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
ISO 3:1973, Preferred numbers – Series of preferred numbers
3 Terms and definitions
For the purposes of this document, the terms and definitions given in Clause 3 of IEC 60127-1,
together with the following definitions, apply.
3.1
through-hole fuse-link
UMF designed for soldering directly into a printed wiring board, with insertion of its leads in
suitably designed holes
3.2
surface mount fuse-link
UMF designed for direct conductive attachment by solder or other means on to the surface of a
substrate, without insertion of its leads in suitably designed holes or sockets
3.3
land
portion of a conductive pattern usually but not exclusively used for the connection and/or
attachment of components (see IEC 60194)
NOTE Further definitions which may be useful in the application of surface mount fuse-links may be found in
3.
IEC 60115-1 and IEC 60115-8
4 General requirements
See IEC 60127-1.
5 Standard ratings
5.1 Rated voltage
See standard sheets.
5.2 Rated current
See Table 1 for preferred ratings.
5.3 Rated breaking capacity
See standard sheets.
___________
There exists a consolidated version (2002).
This standard has been withdrawn.

– 8 – 60127-4  IEC:2005+A1:2008+A2:2012
6 Marking
In addition to the requirements of Clause 6 in IEC 60127-1, the following criteria concerning
UMF shall be observed and marked:
6.1 Addition:
e) For fuse-links rated at 250 V, a symbol denoting the breaking capacity. This symbol shall
be placed between the marking for rated current and the marking for rated voltage.
These symbols are as follows:
H: denoting high-breaking capacity;
I: denoting intermediate-breaking capacity;
L: denoting low-breaking capacity.
f) The distinctive symbol shown in Figure 1.
g) The letters a.c. before the voltage for devices designed solely for alternating current
application.
6.4 Colour coding for universal modular fuse-links
Under consideration.
6.5 Where marking is impractical due to space limitations, the relevant information should
appear on the smallest package and in the manufacturer’s technical literature.
7 General notes on tests
In addition to the requirements of Clause 7 in IEC 60127-1, the following criteria shall be
observed:
7.2 Addition:
7.2.1 For testing of individual fuse ratings according to standard sheets 1 and 2, see Table 2.
For fuse-links designed and rated both for a.c. and d.c., the number of fuse-links required
is 63. For fuse-links designed only for a.c., the number of fuse-links required is 48. There are
nine spares.
For the maximum ampere rating of a homogeneous series according to standard sheets 1
and 2, see Table 3. For fuse-links designed and rated both for a.c. and d.c., the number of
fuse-links required is 53. For fuse-links designed only for a.c., the number of fuse-links
required is 48. There are 19 spares.
For the minimum ampere rating of a homogeneous series according to standard sheets 1 and
2, see Table 4. For fuse-links designed and rated both for a.c. and d.c., the number of fuse-
links required is 38. For fuse-links designed only for a.c., the number of fuse-links required
is 33. There are 16 spares.
60127-4  IEC:2005+A1:2008+A2:2012 – 9 –
7.3 Fuse-bases for tests
7.3.1 General requirements
Fuse-links shall be mounted upon the appropriate test board (see 7.3.2 or 7.3.3 as appropriate)
by soldering.
This test board shall then be mounted on the test fuse-base (Figure 4). 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 (0,070 mm above 6,3 A for rated
currents above 5 A).
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-links 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-links under test. 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 mm².
7.3.2 Through-hole fuse-links (standard sheet 1)
For electrical tests upon fuse-links covered by standard sheet 1, the fuse-link shall be mounted
on the test board, as shown in Figure 2 in the pair of holes appropriate to the spacing of the
terminations.
7.3.3 Surface mount fuse-links (standard sheet 2)
For electrical tests upon fuse-links covered by standard sheet 2, the fuse-link shall be mounted
on the test board, as shown in Figure 3. See Annex A for guidance.
8 Dimensions and construction
8.1 Dimensions
The dimensions of the UMFs shall comply with the relevant standard sheets.
Compliance is checked by measurement of length, width and height.
For fuse-links to standard sheet 1, the termination spacing is checked. 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.
8.2 Construction
The fuse-element shall be completely enclosed.
The UMF shall withstand the heat and chemical exposure of a printed circuit board or other
substrate assembly operations with its performance unimpaired.
Compliance is checked by the resistance to soldering heat test as specified in 8.7.

– 10 – 60127-4  IEC:2005+A1:2008+A2:2012
8.3 Terminations
8.3.1 Through-hole fuse-links
Terminations shall be firmly attached so that it is not possible to remove them without
damaging the UMF.
Compliance is checked by carrying out the following test.
The samples are preconditioned by immersion in water for 24 h at a temperature between
15 °C and 35 °C.
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 fuses for each test. After testing, the terminations shall remain firmly
attached. The voltage drop shall be measured in accordance with 9.1, and shall not exceed the
maximum allowed in Table 1. Bending test Ub is omitted if the terminations are less than
5 mm.
8.3.2 Surface mount fuse-links
The fuse-links shall be mounted on the test board as shown in Figure 3. The test board, with
the fuse-links on the underside, shall be placed in the bending jig as shown in Figure 5. The
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 the test, the terminations shall remain firmly attached, and the voltage drop shall be
measured in accordance with 9.1, and shall not exceed the maximum allowed in Table 1.
8.4 Alignment and configuration of terminations
The termination configuration and spacing shall be as specified in the standard sheets.
NOTE 1 Through-hole fuse-links
For through-hole mounting of UMFs (standard sheet 1), the dimensions shown on the standard sheets 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 mount fuse-links
For surface mounting of UMFs (standard sheet 2), electrical and electronic circuit designers are advised to design
substrate land areas to receive UMFs 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
See IEC 60127-1.
60127-4  IEC:2005+A1:2008+A2:2012 – 11 –
8.6 Solderability of terminations
8.6.1 Through-hole fuse-links
The fuse-links shall be subjected to Test Ta of IEC 60068-2-20:2008, using Method 1, with the
following conditions:
Ageing: None (as received)
Immersion conditions: 235 °C ± 5 °C, 2 s ± 0,5 s 250 °C ± 3 °C, 3 s ± 0,3 s
Depth of immersion: 2,0 mm ± 0,5 mm (from seating plane)
Flux type: Non-activated
Screen: A screen should be used.
After the test, the dipped surface shall be covered with a smooth and bright solder coating, with
no more than small amounts of scattered imperfections such as pin-holes or un-wetted or de-
wetted areas. These imperfections shall not be concentrated in one area. 10 × magnification
shall be used.
A different solder bath temperature may be chosen because of the usage of various solders.
The relevant combination of the solder bath temperature and the solder alloy shall be chosen
according to IEC 60068-2-20:2008, Table 1.
8.6.2 Surface mount fuse-links
The fuse-links shall be subjected to Test Td tested according to 6.2 of IEC 60068-2-58:2004,
with the following conditions:
Ageing: None (as received)
Immersion conditions: 235 °C ± 5 °C, 2 s ± 0,2 s for wave soldering application
215 °C ± 3 °C, 3 s ± 0,3 s for reflow soldering application
245 °C ± 5 °C, 3 s ± 0,3 s
Depth of immersion: The terminations shall be immersed successively in such a way
that the entire metal surfaces are covered by the solder bath
Flux type: Non-activated
After the test, the contact areas shall be covered with a smooth and bright solder coating with
no more than small amounts of scattered imperfections such as pin-holes or un-wetted or de-
wetted areas. These imperfections shall not be concentrated in one area. 10 × magnification
shall be used.
A different solder bath temperature may be chosen because of the usage of various solders.
The relevant combination of the solder bath temperature and the solder alloy shall be chosen
according to IEC 60068-2-58:2004 Table 2.
8.7 Resistance to soldering heat
8.7.1 Through-hole fuse-links
The fuse-links shall be subjected to Test Tb of IEC 60068-2-20:2008, Method 1A, with the
following conditions:
Ageing: None (as received)
Immersion conditions: 260 °C ± 5 °C, 10 s ± 1 s
Depth of immersion: 2,0 mm ± 0,5 mm (from seating plane)
Flux type: Activated
Screen: A screen should be used.

– 12 – 60127-4  IEC:2005+A1:2008+A2:2012
After the test, the fuse-link shall not be cracked. Marking shall be readable, and colour coding,
if used, shall not have changed colour.
The voltage drop is measured as specified in 9.1, and shall not exceed the maximum values
specified in Table 1.
8.7.2 Surface mount fuse-links
The fuse-links shall be subjected to Test Td tested according to 6.2 of IEC 60068-2-58, with
the following conditions:
Ageing: None (as received)
Immersion conditions: 260 °C ± 5 °C, 10 s ± 1 s
Depth of immersion: 10 mm
Flux type: Activated
After the test, the fuse-link shall not be cracked. Marking shall be readable and colour coding,
if used, shall not have changed colour.
The voltage drop is measured as specified in 9.1, and shall not exceed the maximum values
specified in Table 1.
NOTE For some designs, it may be necessary to use a less severe test. This should be in accordance with the
manufacturer’s recommendations, and should be recorded in the test report.
9 Electrical requirements
9.1 Voltage drop
For measurement of voltage drop, see IEC 60127-1.
The voltage drop shall be measured at the points marked U in Figure 2 for through-hole fuse-
links and in Figure 3 for surface mount fuse-links, using the test fuse-base shown in Figure 4
(see 7.3).
Values given in Table 1 apply.
9.2 Time/current characteristics
9.2.1 Time/current characteristics at normal ambient temperature
At 1,25 times rated current not less than 1 h (after completing endurance test).
At 2 times rated current not exceeding 2 min.
Pre-arcing time at 10 times rated current according to the following types:
Type FF: less than 0,001 s
Type F: from 0,001 s to 0,01 s
Type T: greater than 0,01 s to 0,1 s
Type TT: greater than 0,100 s to 1,00 s
9.2.2 Test at elevated temperature
None specified.
60127-4  IEC:2005+A1:2008+A2:2012 – 13 –
9.2.3 Test procedure
See IEC 60127-1.
9.2.4 Presentation of results
See IEC 60127-1.
9.3 Breaking capacity
9.3.1 Addition:
In the case of fuse-links in which any component is organic (such as with a moulded body), the
recovery voltage shall be maintained for 5 min after the fuse has operated.
Typical test circuits for a.c. and d.c. are given in Figure 6.
For low-breaking capacity fuse-links, the power factor of the a.c. test circuit shall be greater
than 0,95. To obtain this result, the circuit current shall be adjusted by the use of resistors of
negligible inductance.
For intermediate-breaking capacity fuse-links, the power factor of the a.c. test circuit shall be
between 0,8 and 0,9.
For high-breaking capacity fuse-links, the power factor of the a.c. test circuit shall be between
0,7 and 0,8.
The time constant of the d.c. test circuit for low-breaking capacity fuse-links shall be less than
1 ms. To obtain this result, the circuit current shall be adjusted by the use of resistors of
negligible inductance; additionally, the total inductance of the test circuit and source of supply
shall be less than 1 mH.
The time constant for the d.c. test circuit for intermediate-breaking capacity fuses shall be
+10 +10
1,5 ms % and for high-breaking capacity it shall be 2,3 ms %.
0 0
Where difficulties in testing arise, these limits may be exceeded with the permission of the
manufacturer. For tests at lower prospective currents, the inductance of the circuit shall remain
constant and the current shall be adjusted by changing the resistance only.
9.3.2 Criteria for satisfactory performance
Addition:
The UMF shall operate satisfactorily without any of the following phenomena:
− illegibility of marking after test.
The following phenomena are neglected:
− black spots or other marks on the fuse-link terminations.
9.3.3
Replacement:
After the breaking capacity test, the insulation resistance shall be measured with a d.c. voltage
equal to twice the rated voltage of the fuse-link. The resistance shall not be less than 0,1 MΩ.

– 14 – 60127-4  IEC:2005+A1:2008+A2:2012
9.4 Endurance tests
See IEC 60127-1.
9.5 Maximum sustained dissipation
See IEC 60127-1.
9.6 Pulse tests
None specified.
9.7 Fuse-link temperature
Replacement:
In place of the test in 9.7 of IEC 60127-1, the following test is performed during the final 5 min
of the endurance test at 1,25 I :
N
a) for fuse-links according to standard sheet 1 the temperature rise above ambient
temperature shall be measured at the hottest spot found on the surface of the fuse-link,
using a fine wire thermocouple (or other measuring methods that do not appreciably affect
the temperature). The temperature rise shall not exceed 70 75 K for fuse-links with rated
current up to and including 6,3 A and 85 95 K for rated current above 6,3 A;
b) for fuse-links according to standard sheet 2 the temperature rise above ambient
temperature shall be measured on the terminals of the fuse-link soldered to the relevant

test board, using a fine wire thermocouple not larger than 0,21 mm (or other measuring
methods that do not appreciably affect the temperature). The temperature rise shall not
exceed 85 95 K.
9.8 Operating overvoltage
During the breaking capacity tests, the voltage across the fuse shall be monitored by a suitable
oscilloscope and probe system, operated in such a way as to indicate and record the voltage
for a time which includes the interval from the moment of closure of the contactor until current
through the fuse-link is extinguished to a value of less than 10 mA (a suitable oscilloscope
should be capable of recording any overvoltage that persists for 5 µs or longer).
The maximum voltage in the interval shall be recorded. In no case shall it be higher than the
value of maximum operating overvoltage given on the standard sheet.

60127-4  IEC:2005+A1:2008+A2:2012 – 15 –
Table 1 – Maximum values of voltage drop and sustained dissipation
Rated current Maximum voltage drop Maximum sustained dissipation
mV mW
32 mA Under consideration Under consideration
50 mA Under consideration
Under consideration
63 mA Under consideration Under consideration
80 mA Under consideration Under consideration
100 mA 1 300 200
125 mA 1 000 200
160 mA 1 000 240
200 mA  1 000 500
250 mA 800 500
315 mA 750 500
400 mA 700 500
500 mA 600 500
630 mA 500 500
800 mA 400 500
1 A 300 500
1,25 A 300 1 000
1,6 A 300 1 000
2 A 300 1 000
2,5 A
300 1 200
3,15 A 300 1 500
4 A 300 2 000
5 A 300 2 500
6,3 A
300 3000
8 A 220 3000
10 A 220 3500
If intermediate rated currents are required, they shall be chosen from the series R20 or R40 according to ISO 3.
NOTE The values indicated in Table 1 apply to low-breaking capacity only. Values for intermediate-breaking
capacity and high-breaking capacity are under consideration.

– 16 – 60127-4 IEC:2005+A1:2008+A2:2012

Table 2 − Testing schedule for individual ampere ratings
Universal modular fuse-link number
Subclause Description
1 4 7 10 13 16 19 22 25 28 31 34 37 40 43 46 49 52 55 58 61
2 5 8 11 14 17 20 23 26 29 32 35 38 41 44 47 50 53 56 59 62
3 6 9 12 15 18 21 24 27 30 33 36 39 42 45 48 51 54 57 60 63
9.7 Temperature rise   X X
9.5 Maximum sustained dissipation   X X
9.4 Endurance test   X X
9.2.1 Time/current characteristic 10 I       X
N
2 I           X
N
1,25 I   X X
N
9.3 Breaking capacity
Rated breaking capacity a.c.    X
d.c.     X
5 times the rated current a.c.     X
d.c.      X
10 times the rated current a.c.       X
d.c.        X
50 times the rated current a.c.        X
d.c.         X
250 times the rated current a.c.          X
d.c.          X
9.3.3 Insulation resistance    X X X X  X X X X X X
8.3 Fuse-link terminations X X
8.5 Soldered joints   X X   X     X
a
6.2 Legibility and indelibility of marking   X X   X     X
8.6 Solderability  X
8.7 Resistance to soldering heat  X
A total of 63 fuse-links (48 for a.c. use only, omit d.c. breaking capacity samples) of which nine are kept as spares. Samples 1 to 12 are chosen at random.
Samples 13 to 63 (48) are soldered to the appropriate test board and sorted in descending order of voltage drop.
a
This subclause is to be found in IEC 60127-1.

60127-4 IEC:2005+A1:2008+A2:2012    – 17 –

Table 3 – Testing schedule for maximum ampere rating of a homogeneous series
Fuse-link numbers
Subclause Description 1-6 7 10 13-18 19 22-26 27-31 32-41 42 45 48 51
8 11 20 43 46 49 52
9 12 21 44 47 50 53
9.7 Temperature rise   X
9.5 Maximum sustained dissipation   X
9.4 Endurance test   X
9.2.1 Time/current characteristics  10 I     X
N
2 I      X
N
1,25 I  X
N
9.3 Rated breaking capacity a.c.   X
d.c.    X
9.3.3 Insulation resistance    X X
8.3 Fuse-link terminations X
8.5 Soldered joints   X   X X
a
6.2 Legibility and indelibility of marking   X   X X
8.6 Solderability  X
8.7 Resistance to soldering heat  X
A total of 53 fuse-links (48 for a.c. use only, omit d.c. breaking capacity samples) of which 19 are kept as spares. Samples 1 to 12 are chosen at random.
Samples 13 to 53 (48) are soldered to the test board and sorted in descending order of voltage drop.
a
This subclause is to be found in IEC 60127-1.

– 18 – 60127-4  IEC:2005+A1:2008+A2:2012
Table 4 – Testing schedule for minimum ampere rating of a homogeneous series
Fuse-link numbers in decreasing value of voltage drop
Subclause Description
1-6 7 10 13-17 18-22 23-32 33 36
8 11  34 37
9 12 35 38
9.4 Endurance test X
9.2.1 Time/current 10 I X
N
characteristics
X
2 IN
9.3 Rated breaking a.c.  X
capacity
d.c. (if   X
applicable)
A total of 38 fuse-links (33 for a.c. use only, omit d.c. breaking capacity samples) of which 16 are kept as spares.

The samples are soldered to the test board and sorted in descending order of voltage drop.

60127-4  IEC:2005+A1:2008+A2:2012 − 19 −

Figure 1 – Unique identifying symbol for UMFs
Dimensions in millimetres
Key
O copper layer, thickness 0,035 mm (0,070 mm for rated currents above 6,3 5 A)
U connection for voltage drop measurement
n 1, 2, 3, 4 or 5
e 2,50 mm
W 5,0 mm for rated current up to and including 6,3 5 A
7,5 mm for rated current above 6,3 5 A

NOTE A mechanical device may be used as long as it is demonstrated that the results are the same.

Figure 2 – Test board for through-hole fuse-links

– 20 – 60127-4  IEC:2005+A1:2008+A2:2012
Dimensions in millimetres
2T
P
Track width
U O U
(20)
Solder resist
IEC  137/05
Key
O copper layer, thickness 0,035 mm (0,070 mm for rated currents above 6,3 5 A)
U connection for voltage drop measurement
W 5,0 mm (7,5 mm for rated currents above 6,3 5 A). For small devices, it may be necessary to use reduced
track widths, representing normal use of these devices. This should be recorded in the test report and in the
manufacturer's literature.
P terminal spacing
R refer to standard sheet 2, page 1
T refer to standard sheet 2, page 1

NOTE 1 Solder resist to be applied in hatched areas.
NOTE 2 The land areas should be suitably prepared for soldering.
NOTE 3 A mechanical device may be used as long as it is demonstrated that the results are the same (not
applicable to 8.7).
Figure 3 − Test board for surface mount fuse-links

10,0
∅4,2
R1,5
0,5
W
16,5
60127-4  IEC:2005+A1:2008+A2:2012 − 21 −

Figure 4a – Through-hole fuse-link (printed circuit track underneath)

Figure 4b – Surface mount fuse-link (printed circuit track on top)
Dimensions in millimetres
H
30 40
IEC  606/96
Key
A base of low heat conducting material, F printed circuit board (see Figures 2 and 3)
thickness 10 mm G space between UMF body and board equals
B brass electrodes 10 mm x 10 mm    (0,5 ± 0,25) mm
C UMF soldered in place H top view of base with brass electrodes
D fixing screws J silver-plated brass washer (two places)
E contact screws holding solder terminal K silver-plated brass screw to make contact with the
conducting surface on top of the printed circuit board
(two places)
Figure 4 – Test fuse base
– 22 – 60127-4  IEC:2005+A1:2008+A2:2012
Dimensions in millimetres
Standard printed
Test sample
wiring board
Solder
Support
45 ± 2
45 ± 2
Radius = 340 Width = 45
IEC  607/96
Standard printed wiring
board before the test
Solder
...