SIST EN 60127-4:2006
(Main)Miniature fuses -- Part 4: Universal modular fuse-links (UMF) - Through-hole and surface mount types
Miniature fuses -- Part 4: Universal modular fuse-links (UMF) - Through-hole and surface mount types
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.
Geräteschutzsicherungen -- Teil 4: Welteinheitliche modulare Sicherungseinsätze (UMF) - Bauarten für Steck- und Oberflächenmontage
Coupe-circuit miniatures -- Partie 4: Eléments de remplacement modulaires universels (UMF) - Types de montage en surface et montage par trous
La présente partie de la EN 60127 s'applique aux éléments de remplacement modulaires universels (UMF) conçus pour le montage sur circuit imprimé et autres substrats, et employés pour la protection d'appareils électriques, de matériels électroniques et de leurs éléments constituants, normalement utilisés à l'intérieur. Elle n'est pas applicable aux éléments de remplacement pour les appareils destinés à être employés dans des conditions particulières, telles que des atmosphères corrosives ou explosives. La présente norme renvoie en outre aux exigences de la EN 60127-1.
Miniaturne varovalke – 4. del: Univerzalni modularni taljivi vložki – Skoznji vložki in vložki za površinsko montažo (IEC 60127-4:2005)
Ta del standarda IEC 60127 se nanaša na univerzalne modularne taljive vložke (UMF) za tiskane tokokroge in sisteme z drugo podlago, ki se uporabljajo za zaščito električnih aparatov, elektronske opreme in delov njenih komponent, ki so namenjeni za notranjo uporabo. Ne velja za taljive vložke za aparate, namenjene uporabi pod posebnimi pogoji, npr. v korozivni ali eksplozivni atmosferi. Te varovalke morajo običajno montirati ali zamenjati samo ustrezno usposobljene osebe s posebno opremo. Taljivi vložki za uporabo v držalih varovalk so v obravnavi. Ta standard se poleg tega uporablja za zahteve iz standarda IEC 60127-1. Cilji tega dela standarda IEC 60127 so enaki, kot je določeno v standardu IEC 60127-1, z dodatno zahtevo stopnje nezmožnosti zamenljivosti.
General Information
Relations
Standards Content (Sample)
SLOVENSKI SIST EN 60127-4:2006
STANDARD
januar 2006
Miniaturne varovalke – 4. del: Univerzalni modularni taljivi vložki – Skoznji
vložki in vložki za površinsko montažo (IEC 60127-4:2005)
(istoveten EN 60127-4:2005)
Miniature fuses - Part 4: Universal modular fuse-links (UMF) - Through-hole and
surface mount types (IEC 60127-4:2005)
ICS 29.120.50 Referenčna številka
SIST EN 60127-4:2006(en)
© Standard je založil in izdal Slovenski inštitut za standardizacijo. Razmnoževanje ali kopiranje celote ali delov tega dokumenta ni dovoljeno
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EUROPEAN STANDARD EN 60127-4
NORME EUROPÉENNE
EUROPÄISCHE NORM April 2005
ICS 29.120.50 Supersedes EN 60127-4:1996 + A1:2002 + A2:2003
English version
Miniature fuses
Part 4: Universal modular fuse-links (UMF) –
Through-hole and surface mount types
(IEC 60127-4:2005)
Coupe-circuit miniatures Geräteschutzsicherungen
Partie 4: Eléments de remplacement Teil 4: Welteinheitliche modulare
modulaires universels (UMF) – Sicherungseinsätze (UMF) –
Types de montage en surface Bauarten für Steck- und
et montage par trous Oberflächenmontage
(CEI 60127-4:2005) (IEC 60127-4:2005)
This European Standard was approved by CENELEC on 2005-03-01. CENELEC members are bound to
comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European
Standard the status of a national standard without any alteration.
Up-to-date lists and bibliographical references concerning such national standards may be obtained on
application to the Central Secretariat or to any CENELEC member.
This European Standard exists in three official versions (English, French, German). A version in any other
language made by translation under the responsibility of a CENELEC member into its own language and
notified to the Central Secretariat has the same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Cyprus, Czech
Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden,
Switzerland and United Kingdom.
CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
Central Secretariat: rue de Stassart 35, B - 1050 Brussels
© 2005 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 60127-4:2005 E
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EN 60127-4:2005 - 2 -
Foreword
The text of document 32C/362/FDIS, future edition 3 of IEC 60127-4, prepared by SC 32C, Miniature
fuses, of IEC TC 32, Fuses, was submitted to the IEC-CENELEC parallel vote and was approved by
CENELEC as EN 60127-4 on 2005-03-01.
This European Standard supersedes EN 60127-4:1996 + A1:2002 + A2:2003.
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.
The clauses of this standard supplement, modify or replace the corresponding clauses in EN 60127-1.
Where there is no corresponding clause or subclause in this standard, the clause or subclause of
EN 60127-1 applies without modification as far as is reasonable. When this standard states “addition”,
“modification” or “remplacement”, the relevant text in EN 60127-1 is to be adapted accordingly.
The following dates were fixed:
– latest date by which the EN has to be implemented
at national level by publication of an identical
national standard or by endorsement (dop) 2005-12-01
– latest date by which the national standards conflicting
with the EN have to be withdrawn (dow) 2008-03-01
Annex ZA has been added by CENELEC.
__________
Endorsement notice
The text of the International Standard IEC 60127-4:2005 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following notes have to be added for the standards indicated:
IEC 60115-1 NOTE Harmonized as EN 60115-1:2001 (modified).
IEC 61191-2 NOTE Harmonized as EN 61191-2:1998 (not modified).
ISO 9453 NOTE Harmonized as EN 29453:1993 (not modified).
__________
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- 3 - EN 60127-4:2005
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
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.
NOTE Where an international publication has been modified by common modifications, indicated by (mod), the relevant
EN/HD applies.
Publication Year Title EN/HD Year
IEC 60068-2-20 1979 Basic environmental testing procedures
+ A2 1987 Part 2: Tests - Test T: Soldering HD 323.2.20 S3 1988
IEC 60068-2-21 1999 Part 2-21: Tests - Test U: Robustness of EN 60068-2-21 1999
terminations and integral mounting
devices
IEC 60068-2-58 2004 Part 2-58: Tests - Test Td: Test methods EN 60068-2-58 2004
for solderability, resistance to dissolution + corr. December 2004
of metallization and to soldering heat of
surface mounting devices (SMD)
IEC 60127-1 1988 Miniature fuses EN 60127-1 1991
Part 1: Definitions for miniature fuses and
general requirements for miniature fuse-
links
A1 1999 A1 1999
A2 2002 A2 2003
IEC 60194 1999 Printed board design, manufacture and - -
assembly - Terms and definitions
IEC 60664-1 1992 Insulation coordination for equipment
+ A1 2000 within low-voltage systems
+ A2 2002 Part 1: Principles, requirements and tests EN 60664-1 2003
IEC 61249-2-7 2002 Materials for printed boards and other EN 61249-2-7 2002
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
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NORME CEI
INTERNATIONALE IEC
60127-4
INTERNATIONAL
Troisième édition
STANDARD
Third edition
2005-01
Coupe-circuit miniatures –
Partie 4:
Eléments de remplacement modulaires
universels (UMF) – Types de montage
en surface et montage par trous
Miniature fuses –
Part 4:
Universal modular fuse-links (UMF) –
Through-hole and surface mount types
IEC 2005 Droits de reproduction réservés Copyright - all rights reserved
Aucune partie de cette publication ne peut être reproduite ni No part of this publication may be reproduced or utilized in any
utilisée sous quelque forme que ce soit et par aucun procédé, form or by any means, electronic or mechanical, including
électronique ou mécanique, y compris la photocopie et les photocopying and microfilm, without permission in writing from
microfilms, sans l'accord écrit de l'éditeur. the publisher.
International Electrotechnical Commission, 3, rue de Varembé, PO Box 131, CH-1211 Geneva 20, Switzerland
Telephone: +41 22 919 02 11 Telefax: +41 22 919 03 00 E-mail: inmail@iec.ch Web: www.iec.ch
CODE PRIX
Commission Electrotechnique Internationale PRICE CODE U
International Electrotechnical Commission
Международная Электротехническая Комиссия
Pour prix, voir catalogue en vigueur
For price, see current catalogue
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60127-4 IEC:2005 – 3 –
CONTENTS
FOREWORD .5
INTRODUCTION .9
1 Scope and object.11
2 Normative references .11
3 Terms and definitions .13
4 General requirements.13
5 Standard ratings.13
6 Marking.15
7 General notes on tests .15
8 Dimensions and construction .17
9 Electrical requirements .23
10 Standard sheets .47
Annex A (informative) Mounting for surface mount fuse-links.55
Bibliography .59
Figure 1 – Unique identifying symbol for UMFs .37
Figure 2 – Test board for through-hole fuse-links .37
Figure 3 − Test board for surface mount fuse-links .39
Figure 4 – Test fuse base .41
Figure 5 – Bending jig for surface mount fuse-links .43
Figure 6 – Test circuits for breaking capacity tests .45
Table 1 – Maximum values of voltage drop and sustained dissipation .29
Table 2 − Testing schedule for individual ampere ratings.31
Table 3 – Testing schedule for maximum ampere rating of a homogeneous series.33
Table 4 – Testing schedule for minimum ampere rating of a homogeneous series.35
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60127-4 IEC:2005 – 5 –
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,
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 provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with an IEC Publication.
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 60127-4 has been prepared by subcommittee 32C: Miniature
fuses, of IEC technical committee 32: Fuses.
This third edition cancels and replaces the second edition (1996), together with amendment 1
(2002) and amendment 2 (2003), and constitutes a technical revision.
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.
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60127-4 IEC:2005 – 7 –
The text of this standard is based on the following documents:
FDIS Report on voting
32C/362/FDIS 32C/366/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
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 this publication will remain unchanged until
the maintenance result 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.
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60127-4 IEC:2005 – 9 –
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
requirements need not be repeated.
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60127-4 IEC:2005 – 11 –
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 60068-2-21:1999, 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
1
requirements for miniature fuse-links
Amendment 1 (1999)
Amendment 2 (2002)
IEC 60194:1999, Printed board design, manufacture and assembly – Terms and definitions
___________
1
There exists a consolidated version (2003).
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60127-4 IEC:2005 – 13 –
IEC 60664-1:1992, Insulation coordination for equipment within low-voltage systems – Part 1:
2
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.
___________
2
There exists a consolidated version (2002).
3
This standard has been withdrawn.
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60127-4 IEC:2005 – 15 –
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.
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60127-4 IEC:2005 – 17 –
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).
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.
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60127-4 IEC:2005 – 19 –
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;
1
− thrust test Ua , applied force 2 N;
2
− 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.
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60127-4 IEC:2005 – 21 –
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, using Method 1, with the
following conditions:
Ageing: None (as received)
Immersion conditions: 235 °C ± 5 °C, 2 s ± 0,5 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 unwetted or
dewetted areas. These imperfections shall not be concentrated in one area. 10×
magnification shall be used.
8.6.2 Surface mount fuse-links
The fuse-links shall be subjected to Test Td of IEC 60068-2-58, 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
Depth of immersion: The terminations shall be immersed successively in such a way
that the entire metal surfaces are covered
...
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