prEN IEC 60127-1:2022

Miniature fuses - Part 1: Definitions for miniature fuses and general requirements for miniature fuse-links

This part of IEC 60127 covers the general requirements and tests applicable to all types of miniature fuse-links (e.g. cartridge fuse-links, sub-miniature fuse-links, universal modular fuse-links and miniature fuse-links for special applications) for the protection of electric appliances, electronic equipment and component parts thereof normally intended to be used indoors. This standard does not apply to fuses intended for the protection of low-voltage electrical installations. These are covered by IEC 60269, Low Voltage Fuses. Specific details covering each major subdivision are given in subsequent parts. This standard does not apply to fuses for appliances intended to be used under special conditions, such as in a corrosive or explosive atmosphere. The object of this standard is a) to establish uniform requirements for miniature fuses so as to protect appliances or parts of appliances in the most suitable way, b) to define the performance of the fuses, so as to give guidance to designers of electrical appliances and electronic equipment and to ensure replacement of fuse-links by those of similar dimensions and characteristics, c) to define methods of testing, d) to define maximum sustained dissipation of fuse-links to ensure good compatibility of stated power acceptance when used with fuse-holders according to this standard (see IEC 60127-6).

Geräteschutzsicherungen - Teil 1: Begriffe für Geräteschutzsicherungen und allgemeine Anforderungen an G-Sicherungseinsätze

Coupe-circuits miniatures - Partie 1: Définitions pour coupe-circuits miniatures et exigences générales pour éléments de remplacement miniatures

Miniaturne varovalke - 1. del: Definicije za miniaturne varovalke in splošne zahteve za miniaturne taljive vložke

General Information

• Status: Not Published
• Publication Date: 30-Oct-2023
• ICS: 29.120.50 - Fuses and other overcurrent protection devices
• Technical Committee: CLC/SR 32C - Miniature fuses
• Drafting Committee: IEC/SC 32C - IEC_SC_32C
• Current Stage: 4060 - Enquiry results established and sent to TC, SR, BTTF - Enquiry
• Start Date: 01-Jul-2022
• Completion Date: 01-Jul-2022
• 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 60127-1:2022 - Miniature fuses - Part 1: Definitions for miniature fuses and general requirements for miniature fuse-links

Relations

• Revises: EN 60127-1:2006/A2:2015 - Miniature fuses - Part 1: Definitions for miniature fuses and general requirements for miniature fuse-links
• Effective Date: 24-Aug-2021
• Revises: EN 60127-1:2006 - Miniature fuses - Part 1: Definitions for miniature fuses and general requirements for miniature fuse-links
• Effective Date: 07-Jun-2022
• Revises: EN 60127-1:2006/A1:2011 - Miniature fuses - Part 1: Definitions for miniature fuses and general requirements for miniature fuse-links
• Effective Date: 23-Jan-2023

Standards Content (Sample)

SLOVENSKI STANDARD
oSIST prEN IEC 60127-1:2022
01-junij-2022

Miniaturne varovalke - 1. del: Definicije za miniaturne varovalke in splošne zahteve

za miniaturne taljive vložke

Miniature fuses - Part 1: Definitions for miniature fuses and general requirements for

miniature fuse-links

Geräteschutzsicherungen - Teil 1: Begriffe für Geräteschutzsicherungen und allgemeine

Anforderungen an G-Sicherungseinsätze

Coupe-circuits miniatures - Partie 1: Définitions pour coupe-circuits miniatures et

exigences générales pour éléments de remplacement miniatures
Ta slovenski standard je istoveten z: prEN IEC 60127-1:2022
ICS:
29.120.50 Varovalke in druga Fuses and other overcurrent
nadtokovna zaščita protection devices
oSIST prEN IEC 60127-1:2022 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN IEC 60127-1:2022
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oSIST prEN IEC 60127-1:2022
32C/600/CDV
COMMITTEE DRAFT FOR VOTE (CDV)
PROJECT NUMBER:
IEC 60127-1 ED3
DATE OF CIRCULATION: CLOSING DATE FOR VOTING:
2022-04-08 2022-07-01
SUPERSEDES DOCUMENTS:
32C/588/CD, 32C/594/CC
IEC SC 32C : MINIATURE FUSES
SECRETARIAT: SECRETARY:
China Mr Jianqiang Zou
OF INTEREST TO THE FOLLOWING COMMITTEES: PROPOSED HORIZONTAL STANDARD:
Other TC/SCs are requested to indicate their interest, if
any, in this CDV to the secretary.
FUNCTIONS CONCERNED:
EMC ENVIRONMENT QUALITY ASSURANCE SAFETY

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

which they are aware and to provide supporting documentation.
TITLE:

Miniature fuses - Part 1: Definitions for miniature fuses and general requirements for miniature

fuse-links
PROPOSED STABILITY DATE: 2025
NOTE FROM TC/SC OFFICERS:

The mark of changes indicate the revision compared to the CD document (32C/588/CD).

Copyright © 2022 International Electrotechnical Commission, IEC. All rights reserved. It is permitted to download this

electronic file, to make a copy and to print out the content for the sole purpose of preparing National Committee positions.

You may not copy or "mirror" the file or printed version of the document, or any part of it, for any other purpose without

permission in writing from IEC.
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oSIST prEN IEC 60127-1:2022
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1 CONTENTS

2 1 Scope and object .............................................................................................................. 7

3 2 Normative references ....................................................................................................... 7

4 3 Terms and definitions ....................................................................................................... 7

5 4 General requirements ..................................................................................................... 11

6 5 Standard ratings ............................................................................................................. 11

7 6 Marking .......................................................................................................................... 11

8 7 General notes on tests ................................................................................................... 12

9 7.1 Atmospheric conditions for testing ......................................................................... 12

10 7.2 Type tests ............................................................................................................. 13

11 7.3 Fuse-bases for tests .............................................................................................. 13

12 7.4 Nature of supply .................................................................................................... 13

13 8 Dimensions and construction .......................................................................................... 14

14 8.1 Dimensions ........................................................................................................... 14

15 8.2 Construction .......................................................................................................... 14

16 8.3 Terminations ......................................................................................................... 14

17 8.4 Alignment and configuration of terminations .......................................................... 14

18 8.5 Soldered joints ...................................................................................................... 14

19 9 Electrical requirements ................................................................................................... 14

20 9.1 Voltage drop .......................................................................................................... 14

21 9.2 Time/current characteristic .................................................................................... 15

22 9.2.1 Time/current characteristic at normal ambient temperature ........................ 15

23 9.2.2 Test at elevated temperature ..................................................................... 15

24 9.2.3 Test procedure .......................................................................................... 15

25 9.2.4 Presentation of results ............................................................................... 16

26 9.3 Breaking capacity .................................................................................................. 16

27 9.3.1 Operating conditions .................................................................................. 16

28 9.3.2 Criteria for satisfactory performance .......................................................... 17

29 9.3.3 Insulation resistance .................................................................................. 17

30 9.3.4 Type test for fuse-links of homogeneous series ......................................... 17

31 9.4 Endurance tests .................................................................................................... 17

32 9.5 Maximum sustained dissipation ............................................................................. 18

33 9.7 Fuse-link temperature ........................................................................................... 18

34 Annex A (informative) Colour coding for miniature fuse-links ............................................... 19

35 Annex B (informative) Example presentations of time/current characteristic ......................... 21

36 Annex C (informative) Audit testing and surveillance – Guidelines for the application of

37 the principles of IECEE 03 (CB-FCS) to miniature fuse-links .......................................... 23

38 C.1 Introductory remarks ............................................................................................. 23

39 C.2 Overview ............................................................................................................... 23

40 C.3 Terms of reference ................................................................................................ 23

41 C.4 Conformity Assessment Report ............................................................................. 23

42 C.4.1 Product description .................................................................................... 23

43 C.4.2 Identification of significant samples ........................................................... 24

44 C.5 Use of the standard ............................................................................................... 25

45 C.6 Audit test and surveillance programme options ...................................................... 25

46 C.6.1 Audit testing and surveillance – Option 1 ................................................... 26

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47 C.6.2 Audit testing and surveillance – Option 2 ................................................... 26

48 C.6.3 Audit testing and surveillance – Option 3 ................................................... 26

49 C.6.4 Audit testing and surveillance – Option 4 ................................................... 27

50 C.7 Acceptability of audit test results ........................................................................... 28

51 C.8 Acceptability of surveillance results ....................................................................... 28

Annex D (informative) User guide for miniature fuses .......................................................... 21

53 D.1 Introduction .................................................................................................................... 30

54 General .......................................................................................................................... 30

D.2

55 D.3 Properties of miniature fuse-links ................................................................................... 30

56 Different types of fuse-links ............................................................................................ 31

D.4

57 D.4.1 Characteristics ...................................................................................................... 31

58 D.4.2 Breaking capacity .................................................................................................. 32

59 D.4.3 Cartridge fuse-links (IEC 60127-2) ........................................................................ 32

60 Sub-miniature fuse-links (IEC 60127-3) ................................................................. 33

D.4.4

61 D.4.5 Universal Modular Fuse-links (IEC 60127-4) .......................................................... 33

62 D.4.6 Miniature fuse-links for special applications (IEC 60127-7) .................................. 334

63 D.5 Applications .................................................................................................................. 335

64 D.5.1 Applications – Fuse-link selection criteria ............................................................ 335

65 D.5.2 Electrical criteria ................................................................................................. 345

66 D.5.3 Mechanical/physical dimensions .......................................................................... 345

67 D.6 Protection by I t limitation and pulse operation ............................................................. 356

68 D.6.1 I t value .............................................................................................................. 356

69 Pulse operation ................................................................................................... 356

D.6.2

70 D.6.3 I t limitation ......................................................................................................... 356

71 D.7 Direct current (d.c.) applications ................................................................................... 357

72 D.7.1 General information ............................................................................................. 357

73 Battery circuits .................................................................................................... 367

D.7.2

74 D.7.3 Inductive load circuits ............................................................................................ 36

75 D.8 Fuse-holders ................................................................................................................ 368

76 D.8.1 Features .............................................................................................................. 368

77 Safety aspects..................................................................................................... 368

D.8.2

78 D.8.3 Selection of a fuse-holder .................................................................................... 368

80 D.8.4 Exchange of fuse-links under load ....................................................................... 379

81 D.9 Performance on extra-low voltages ............................................................................... 379

82 D.10 ............................................................................................. Influence of ambient temperature 40

83 Bibliography .......................................................................................................................... 40

85 Figure A.1– Layout of colour bands....................................................................................... 19

86 Figure B.1 – Example presentation of time/current characteristic, ratio 2:1 ........................... 21

87 Figure B.2 – Example presentation of time/current characteristic, ratio 3:1 ........................... 22

88 Figure C.1 – Example of a fuse-link description .................................................................... 24

90 Table 1 – Prospective current/Breaking capcaity tolereance ................................................. 20

Table A.1 – Colour coding for miniature fuse-links ................................................................ 20

92 Table C.1 – Audit testing for option 3 .................................................................................... 27

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93 Table C.2 – Audit testing for option 4 .................................................................................... 28

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oSIST prEN IEC 60127-1:2022
IEC 60127-1:20XX – 5
95 INTERNATIONAL ELECTROTECHNICAL COMMISSION
97 ___________
99 MINIATURE FUSES –
100
101 Part 1: Definitions for miniature fuses and
102 general requirements for miniature fuse-links
103
104
105 FOREWORD

106 1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising

107 all national electrotechnical committees (IEC National Committees). The object of IEC is to promote

108 international co-operation on all questions concerning standardization in the electrical and electronic fields. To

109 this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,

110 Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC

111 Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested

112 in the subject dealt with may participate in this preparatory work. International, governmental and non-

113 governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely

114 with the International Organization for Standardization (ISO) in accordance with conditions determined by

115 agreement between the two organizations.

116 2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international

117 consensus of opinion on the relevant subjects since each technical committee has representation from all

118 interested IEC National Committees.

119 3) IEC Publications have the form of recommendations for international use and are accepted by IEC National

120 Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC

121 Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any

122 misinterpretation by any end user.

123 4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications

124 transparently to the maximum extent possible in their national and regional publications. Any divergence

125 between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in

126 the latter.

127 5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity

128 assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any

129 services carried out by independent certification bodies.

130 6) All users should ensure that they have the latest edition of this publication.

131 7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and

132 members of its technical committees and IEC National Committees for any personal injury, property damage or

133 other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and

134 expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC

135 Publications.

136 8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is

137 indispensable for the correct application of this publication.

138 9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of

139 patent rights. IEC shall not be held responsible for identifying any or all such patent rights.

140

141 International Standard IEC 60127-1 has been prepared by subcommittee 32C: Miniature fuses,

142 of IEC technical committee 32: Fuses.

143 This third edition cancels and replaces the second edition (2006), together with amendment 1

144 (2011) and amendment 2 (2015), and constitutes a technical revision.

145 This edition includes the following technical changes with respect to the previous edition:

146 a) modified subclause 6.3 to clarify the marking items;

147 b) modified subclause 9.3.1 to introduce a tolerance for the prospective current for the

148 breaking capacity test;
149 c) deleted clause 9.6, Pulse test;
150 d) added annex D user guide for miniature fuse-links.
151
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152 The text of this standard is based on the following documents:
FDIS Report on voting
32C/***/*** 32C/***/***
153

154 Full information on the voting for the approval of this standard can be found in the report on

155 voting indicated in the above table.

156 This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.

157 This Part 1 of the IEC 60127 series covers definitions, general requirements and tests

158 applicable to all types of miniature fuses (e.g. cartridge fuse-links, sub-miniature fuse-links,

159 universal modular fuse-links and miniature fuse-links for special applications). All subsequent

160 parts of the complete series are to be read in conjunction with this Part 1.

161 IEC 60127 consists of the following parts, under the general heading Mi ni ature fuses:

162 IEC 60127, Miniature fuses (general title).

163 IEC 60127-1, Miniature fuses – Part 1: Definitions for miniature fuses and general

164 requirements for miniature fuse-links
165 IEC 60127-2, Miniature fuses – Part 2: Cartridge fuse-links
166 IEC 60127-3, Miniature fuses – Part 3: Sub-miniature fuse-links

167 IEC 60127-4, Miniature fuses – Part 4: Universal modular fuse-links (UMF) – Through-hole

168 and surface mount types

169 IEC 60127-5, Miniature fuses – Part 5: Guidelines for quality assessment of miniature

170 fuselinks
171 IEC 60127-6, Miniature fuses – Part 6: Fuse-holders for miniature fuse-links

172 IEC 60127-7, Miniature fuses – Part 7: Miniature fuse-links for special applications

173 IEC 60127-8, Miniature fuses – Part 8: Fuse resistors with particular overcurrent protection

174 IEC 60127-9, (Free for further documents)
175 IEC 60127-10, Moved to IEC 60127-1 as an Annex.

176 The committee has decided that the contents of the base publication and its amendments will

177 remain unchanged until the stability date indicated on the IEC web site under

178 "http://webstore.iec.ch" in the data related to the specific publication. At this date, the

179 publication will be
180 • reconfirmed,
181 • withdrawn,
182 • replaced by a revised edition, or
183 • amended.
184
185
186
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IEC 60127-1:20XX – 7
187 MINIATURE FUSES –
188
189 Part 1: Definitions for miniature fuses and
190 general requirements for miniature fuse-links
191
192
193
194 1 Scope and object

195 This part of IEC 60127 covers the general requirements and tests applicable to all types of

196 miniature fuse-links (e.g. cartridge fuse-links, sub-miniature fuse-links, universal modular

197 fuse-links and miniature fuse-links for special applications) for the protection of electric

198 appliances, electronic equipment and component parts thereof normally intended to be used

199 indoors.

200 This standard does not apply to fuses intended for the protection of low-voltage electrical

201 installations. These are covered by IEC 60269, Low Voltage Fuses.

202 Specific details covering each major subdivision are given in subsequent parts.

203 This standard does not apply to fuses for appliances intended to be used under special

204 conditions, such as in a corrosive or explosive atmosphere.
205 The object of this standard is

206 a) to establish uniform requirements for miniature fuses so as to protect appliances or parts

207 of appliances in the most suitable way,

208 b) to define the performance of the fuses, so as to give guidance to designers of electrical

209 appliances and electronic equipment and to ensure replacement of fuse-links by those of

210 similar dimensions and characteristics,
211 c) to define methods of testing,

212 d) to define maximum sustained dissipation of fuse-links to ensure good compatibility of

213 stated power acceptance when used with fuse-holders according to this standard (see

214 IEC 60127-6).
215 2 Normative references

216 The following referenced documents are indispensable for the application of this document.

217 For dated references, only the edition cited applies. For undated references, the latest edition

218 of the referenced document (including any amendments) applies.
219 IEC 60038, IEC standard voltages

220 IEC 60127-6:2014, Miniature fuses – Part 6: Fuse-holders for miniature fuse-links

221 3 Terms and definitions
222 For the purposes of this document, the following definitions apply.
223 3.1
224 fuse

225 device that, by the fusing of one or more of its specially designed and proportioned

226 components, opens the circuit in which it is inserted by breaking the current when this

227 exceeds a given value for a sufficient time
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228 NOTE The fuse comprises all the parts that form the complete device.
229 3.2
230 miniature fuse
231 fuse in which the fuse-link is a miniature fuse-link
232 3.3
233 fuse-link

234 part of a fuse including the fuse-element(s) intended to be replaced after the fuse has

235 operated
236 3.4
237 enclosed fuse-link

238 fuse-link in which the fuse-element is totally enclosed, so that during operation within its

239 rating it cannot produce any harmful external effects, e.g. due to development of an arc, the

240 release of gas or the ejection of flame or metallic particles
241 3.5
242 miniature fuse-link

243 enclosed fuse-link for the protection of electric appliances, electronic equipment and

244 component parts thereof normally intended to be used indoors
245 3.5.1
246 cartridge fuse-link

247 enclosed miniature fuse-link of rated breaking capacity not exceeding 2 kA and which has at

248 least one of its principle dimensions not exceeding 10 mm
249 Note 1 to entry Principle dimensions are length, width, height and diameter.
250 3.5.2
251 miniature fuse-link for special applications

252 enclosed miniature fuse-link which is not covered in IEC 60127-2, IEC 60127-3 or IEC 60127-4 and of rated

253 breaking capacity not exceeding 50 kA and having a width and height not exceeding 12 mm and a length not

254 exceeding 50 mm
255 3.5.3
256 sub-miniature fuse-link

257 miniature fuse-link of which the case (body) has no principal dimension exceeding 10 mm

258 Note 1 to entry Principal dimensions are length, width, height and diameter.
259 3.5.4
260 universal modular fuse-link

261 miniature fuse-link primarily adapted for direct electrical connection to printed circuit boards

262 or other conductive substrates, incorporating features designed to provide a degree of non-

263 interchangeability where necessary
264 3.6
265 fuse-link contact

266 conductive part of a fuse-link designed to engage with a fuse-base contact or with a fuse-

267 carrier contact
268 3.7
269 fuse-holder
270 combination of a fuse-base with its fuse-carrier
271 3.8
272 fuse-base
273 fuse-mount

274 fixed part of a fuse provided with contacts and terminals for connection to the system

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IEC 60127-1:20XX – 9
275 3.9
276 fuse-base contact
277 fuse-mount contact

278 conductive part of a fuse-base, connected to a terminal designed to engage with a fuse-

279 carrier contact or with a fuse-link contact
280 3.10
281 fuse-carrier
282 movable part of a fuse designed to carry a fuse-link
283 3.11
284 fuse-carrier contact

285 conductive part of a fuse-carrier connected to a fuse-link contact and designed to engage with

286 a fuse-base contact
287 3.12
288 fuse-element
289 part of the fuse-link designed to melt when the fuse operates
290 3.13
291 homogeneous series (of fuse-links)

292 series of fuse-links, deviating from each other only in such characteristics that, for a given

293 test, the testing of one or a reduced number of particular fuse-links of the series may be taken

294 as representative of all the fuse-links of the series

295 Note 1 to entry Fuse-links are considered as forming a homogeneous series when the characteristics comply with

296 the following:
297 – the bodies have the same dimensions, material and method of manufacture;

298 – the caps or other end closures of the body have the same dimensions, materials and method of attachment and

299 sealing;

300 – the granular filler, if any, of the body is of the same material and completeness of filling. It should be of the

301 same size or any variation of the grain size with current rating should be monotonous;

302 – the fuse-elements are of the same material with the same principles of design and construction; any changes of

303 fuse-element dimensions with current rating should be monotonous;
304 – the rated voltage is the same;

305 – for low-breaking capacity fuse-links it is only necessary to test the highest rated breaking capacity in a

306 homogeneous series.
307 3.14
308 rating

309 general term employed to designate the characteristic values that together define the working

310 conditions upon which the tests are based and for which the fuse is designed
311 Examples of rated values usually stated for fuses:
312 − voltage (U );
313 − current (I );
314 − breaking capacity.
315 3.15
316 time/current characteristics (of a fuse-link)

317 a) For a.c.: curve giving, under stated conditions of operation, the value of time expressed as

318 virtual time as a function of the prospective symmetrical current, expressed as the r.m.s.

319 value

320 b) For d.c.: curve giving, under stated conditions of operation, the value of time expressed as

321 actual time as a function of the d.c. prospective current

322 Note 1 to entry Time/current characteristics usually stated for a fuse-link relate to the pre-arcing time and the

323 operating time.
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324 3.16
325 conventional non-fusing current

326 value of current specified as that which the fuse-link is capable of carrying for a specified time

327 (conventional time) without melting
328 3.17
329 prospective current (of a circuit and with respect to a fuse)

330 current that would flow in a circuit, if a fuse situated therein were replaced by a link of

331 negligible impedance
332 3.18
333 pre-arcing time (melting time)

334 interval of time between the beginning of a current large enough to cause a break in the fuse-

335 element and the instant when an arc is initiated
336 3.19
337 arcing time

338 interval of time between the instant of the initiation of the arc and the instant of final arc

339 extinction
340 3.20
341 operating time (total clearing time)
342 sum of the pre-arcing time and the arcing time
343 3.21
344 virtual time
345 t divided by the value of the square of the value of the prospective current
value of I

346 Note 1 to entry The values of the virtual times, usually stated for a fuse-link, are the values of the pre-arcing time

347 and of the operating time.
348 3.22
349 I t (joule integral)
350 integral of the square of the current over a given time interval:
351
2 2
352 Note 1 to entry The pre-arcing I t is the I
...