prEN IEC 62271-110:2022

High-voltage switchgear and controlgear - Part 110: Inductive load switching

Hochspannungs-Schaltgeräte und -Schaltanlagen - Teil 110: Schalten induktiver Lasten

Appareillage à haute tension - Partie 110: Manœuvre de charges inductives

Visokonapetostne stikalne in krmilne naprave - 110. del: Preklapljanje induktivnega bremena

General Information

• Status: Not Published
• ICS: 29.130.10 - High voltage switchgear and controlgear
• Technical Committee: CLC/TC 17AC - High-voltage switchgear and controlgear
• Drafting Committee: IEC/SC 17A - IEC_SC_17A
• Current Stage: 4020 - Enquiry circulated
• Due Date: 19-Aug-2022
• Completion Date: 19-Aug-2022
• Ref Project: oSIST prEN IEC 62271-110:2022 - High-voltage switchgear and controlgear - Part 110: Inductive load switching

RELATIONS

• Revised: EN IEC 62271-110:2018/AC:2018-03 - High-voltage switchgear and controlgear - Part 110: Inductive load switching
• Effective Date: 29-Mar-2022
• Revised: EN IEC 62271-110:2018 - High-voltage switchgear and controlgear - Part 110: Inductive load switching
• Effective Date: 29-Mar-2022

Standards Content (sample)

SLOVENSKI STANDARD
oSIST prEN IEC 62271-110:2022
01-oktober-2022
Visokonapetostne stikalne in krmilne naprave - 110. del: Preklapljanje
induktivnega bremena
High-voltage switchgear and controlgear - Part 110: Inductive load switching

Hochspannungs-Schaltgeräte und -Schaltanlagen - Teil 110: Schalten induktiver Lasten

Appareillage à haute tension - Partie 110: Manuvre de charges inductives
Ta slovenski standard je istoveten z: prEN IEC 62271-110:2022
ICS:
29.130.10 Visokonapetostne stikalne in High voltage switchgear and
krmilne naprave controlgear
oSIST prEN IEC 62271-110:2022 en

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

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oSIST prEN IEC 62271-110:2022
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oSIST prEN IEC 62271-110:2022
17A/1354/CDV
COMMITTEE DRAFT FOR VOTE (CDV)
PROJECT NUMBER:
IEC 62271-110 ED5
DATE OF CIRCULATION: CLOSING DATE FOR VOTING:
2022-08-19 2022-11-11
SUPERSEDES DOCUMENTS:
17A/1345/CD, 17A/1353/CC
IEC SC 17A : SWITCHING DEVICES
SECRETARIAT: SECRETARY:
Sweden Mr Anne Bosma
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:
High-voltage switchgear and controlgear - Part 110: Inductive load switching
PROPOSED STABILITY DATE: 2030
NOTE FROM TC/SC OFFICERS:

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 62271-110:2022
IEC CDV 62271-110 © IEC 2022 2 17A/1354/CDV
1 CONTENTS

2 FOREWORD ........................................................................................................................... 4

3 1 Scope .............................................................................................................................. 6

4 2 Normative references ...................................................................................................... 6

5 3 Terms and definitions ...................................................................................................... 7

6 4 Type tests ....................................................................................................................... 8

7 4.1 General ................................................................................................................... 8

8 4.2 Miscellaneous provisions for inductive load switching tests ..................................... 8

9 4.3 High-voltage motor current switching tests .............................................................. 9

10 4.3.1 Applicability ..................................................................................................... 9

11 4.3.2 General ........................................................................................................... 9

12 4.3.3 Characteristics of the supply circuits .............................................................. 10

13 4.3.4 Characteristics of the load circuit ................................................................... 11

14 4.3.5 Test voltage ................................................................................................... 11

15 4.3.6 Test-duties .................................................................................................... 12

16 4.3.7 Test measurements ....................................................................................... 12

17 4.3.8 Behaviour and condition of switching device .................................................. 12

18 4.3.9 Test report ..................................................................................................... 13

19 4.4 Shunt reactor current switching tests .................................................................... 14

20 4.4.1 Applicability ................................................................................................... 14

21 4.4.2 General ......................................................................................................... 15

22 4.4.3 Test circuits ................................................................................................... 15

23 4.4.4 Characteristics of the supply circuit ............................................................... 18

24 4.4.5 Characteristics of the connecting leads .......................................................... 18

25 4.4.6 Characteristics of the load circuits ................................................................. 18

26 4.4.7 Earthing of the test circuit .............................................................................. 23

27 4.4.8 Test voltage ................................................................................................... 23

28 4.4.9 Test-duties .................................................................................................... 23

29 Annex A (normative) Calculation of t values ....................................................................... 27

30 Bibliography .......................................................................................................................... 29

32 Figure 1 – Motor switching test circuit and summary of parameters ....................................... 10

33 Figure 2 – Illustration of voltage transients at interruption of inductive current for first

34 phase clearing in a three-phase non-effectively earthed circuit ............................................. 14

35 Figure 3 – Reactor switching test circuit – Three-phase test circuit for in-service load

36 circuit configurations 1 and 2 (Table 2) ................................................................................. 16

37 Figure 4 – Reactor switching test circuit – Single-phase test circuit for in-service load

38 circuit configurations 1, 2 and 4 (Table 2) ............................................................................. 17

39 Figure 5 – Reactor switching test circuit − Three-phase test circuit for in-service load

40 circuit configuration 3 (Table 2) ............................................................................................. 18

41 Figure 6 – Illustration of voltage transients at interruption of inductive current for a

42 single-phase test .................................................................................................................. 26

44 Table 1 – Test-duties at motor current switching tests ........................................................... 12

45 Table 2 – In-service load circuit configurations ..................................................................... 15

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46 Table 3 –Values of prospective transient recovery voltages – Rated voltages 12 kV to

47 170 kV for effectively and non-effectively earthed systems – Switching shunt reactors

48 with isolated neutrals (Table 2: In-service load circuit configuration 1) .................................. 19

49 Table 4 – Values of prospective transient recovery voltages – Rated voltages 100 kV to

50 1 200 kV for effectively earthed systems – Switching shunt reactors with earthed

51 neutrals (See Table 2: In-service load circuit configuration 2) ............................................... 20

52 Table 5 – Values of prospective transient recovery voltages – Rated voltages 12 kV to

53 52 kV for effectively and non-effectively earthed systems – Switching shunt reactors

54 with isolated neutrals (See Table 2: In-service load circuit configuration 3) ........................... 21

55 Table 6 – Values of prospective transient recovery voltages – Rated voltages 12 kV to

56 52 kV for effectively and non-effectively earthed systems – Switching shunt reactors

57 with earthed neutrals (See Table 2: In-service load circuit configuration 4) ........................... 22

58 Table 7 – Load circuit 1 test currents .................................................................................... 22

59 Table 8 – Load circuit 2 test currents .................................................................................... 23

60 Table 9 – Test-duties for reactor current switching tests ....................................................... 24

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oSIST prEN IEC 62271-110:2022
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63 INTERNATIONAL ELECTROTECHNICAL COMMISSION
64 ____________
66 HIGH-VOLTAGE SWITCHGEAR AND CONTROLGEAR –
68 Part 110: Inductive load switching
70 FOREWORD

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

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

73 co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and

74 in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports,

75 Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). Their

76 preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with

77 may participate in this preparatory work. International, governmental and non-governmental organizations liaising

78 with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for

79 Standardization (ISO) in accordance with conditions determined by agreement betw een the two organizations.

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

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

82 interested IEC National Committees.

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

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

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

86 misinterpretation by any end user.

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

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

89 any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.

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

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

92 services carried out by independent certification bodies.

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

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

95 members of its technical committees and IEC National Committees for any personal i njury, property damage or

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

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

98 Publications.

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

100 indispensable for the correct application of this publication.

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

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

103 International Standard IEC 62271-110 has been prepared by subcommittee 17A: Switching

104 devices, of IEC technical committee 17: High-voltage switchgear and controlgear.

105 This fifth edition cancels and replaces the fourth edition published in 2017 and constitutes an

106 editorial revision.

107 This edition includes the following significant technical changes with respect to the previous

108 edition:

109 – references to IEC 62271-100 and IEC 62271-106 have been updated to the latest editions.

110 The text of this International Standard is based on the following documents:
FDIS Report on voting
17A/xxx/FDIS 17A/xxx/RVD
111

112 Full information on the voting for the approval of this International Standard can be found in the

113 report on voting indicated in the above table.
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114 This document has been drafted in accordance with the ISO/IEC Directives, Part 2.

115 A list of all parts of the IEC 62271 series can be found, under the general title High-voltage

116 switchgear and controlgear, on the IEC website.

117 The committee has decided that the contents of this document will remain unchanged until the

118 stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to

119 the specific document. At this date, the document will be
120 • reconfirmed,
121 • withdrawn,
122 • replaced by a revised edition, or
123 • amended.
124
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125 HIGH-VOLTAGE SWITCHGEAR AND CONTROLGEAR –
126
127 Part 110: Inductive load switching
128
129
130
131 1 Scope

132 This part of IEC 62271 is applicable to AC switching devices designed for indoor or outdoor

133 installation, for operation at frequencies of 50 Hz and 60 Hz on systems having voltages above

134 1 000 V and applied for inductive current switching. It is applicable to switching devices

135 (including circuit-breakers in accordance with IEC 62271-100) that are used to switch

136 high-voltage motor currents and shunt reactor currents and also to high-voltage contactors used

137 to switch high-voltage motor currents as covered by IEC 62271-106.

138 Switching unloaded transformers, i.e. breaking transformer magnetizing current, is not

139 considered in this document. The reasons for this are as follows:

140 a) Owing to the non-linearity of the transformer core, it is not possible to correctly model t he

141 switching of transformer magnetizing current using linear components in a test laboratory.

142 Tests conducted using an available transformer, such as a test transformer, will only be

143 valid for the transformer tested and cannot be representative for other transformers.

144 b) As detailed in IEC TR 62271-306, the characteristics of this duty are usually less severe

145 than any other inductive current switching duty. Such a duty may produce severe

146 overvoltages within the transformer winding(s) depending on the re-ignition behaviour of the

147 switching device and transformer winding resonance frequencies.

148 NOTE 1 The switching of tertiary reactors from the high-voltage side of the transformer is not covered by this

149 document.

150 NOTE 2 The switching of shunt reactors earthed through neutral reactors is not covered by this document. However,

151 the application of test results according to this document, on the switching of neutral reactor earthed reactors (4-leg

152 reactor scheme), is discussed in IEC TR 62271-306.
153 2 Normative references

154 The following documents are referred to in the text in such a way that some or all of their content

155 constitutes requirements of this document. For dated references, only the edition cited applies.

156 For undated references, the latest edition of the referenced document (including any

157 amendments) applies.

158 IEC 60050-441:1984, International Electrotechnical Vocabulary – Chapter 441: Switchgear,

159 controlgear and fuses (available at www.electropedia.org)
160 IEC 60050-441:1984/AMD1:2000

161 IEC 62271-1:2017, High-voltage switchgear and controlgear – Part 1: Common specifications

162 for alternating current switchgear and controlgear
163 IEC 62271-1:2017/AMD1:2021

164 IEC 62271-100:2021, High-voltage switchgear and controlgear – Part 100: Alternating current

165 circuit-breakers

166 IEC 62271-106:2021, High-voltage switchgear and controlgear – Part 106: Alternating current

167 contactors, contactor-based controllers and motor-starters
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168 3 Terms and definitions

169 For the purposes of this document, the terms and definitions given in IEC 60050-441,

170 IEC 62271-1 and the following apply.

171 ISO and IEC maintain terminological databases for use in standardization at the following

172 addresses:
173 • IEC Electropedia: available at http://www.electropedia.org/
174 • ISO Online browsing platform: available at http://www.iso.org/obp
175 3.1
176 inductive current

177 power-frequency current drawn by an inductive circuit having a power factor 0,5 or less

178 3.2
179 current chopping

180 abrupt current interruption in a switching device at a point-on-wave other than the natural

181 power-frequency current zero
182 3.3
183 virtual current chopping

184 current chopping in one of the three phases in a three-phase circuit originated by transients in

185 another phase of the circuit
186 3.4
187 suppression peak

188 first peak of the transient voltage to earth on the load side of the switching device following

189 current interruption

190 Note 1 to entry: Suppression peak is not necessarily the absolute maximum of the transient recovery voltage.

191 Previous breakdowns may have appeared at higher voltage values.
192 3.5
193 recovery peak

194 maximum value of the voltage across the switching device occurring when the polarity of the

195 recovery voltage is equal to the polarity of the power-frequency voltage

196 Note 1 to entry: Recovery peak is not necessarily the absolute maximum of the transient recovery voltage. Previous

197 breakdowns may have appeared at higher voltage values.
198 3.6
199 re-ignition

200 resumption of current between the contacts of a mechanical switching device during a breaking

201 operation with an interval of zero current of less than a quarter cycle of power frequency

202 Note 1 to entry: In the case of inductive load switching the initiation of the re-ignition is a high-frequency event,

203 which can be of a single or multiple nature and may in some cases be interrupted without power -frequency follow

204 current.
205 3.7
206 re-ignition-free arcing time window

207 period of arc duration during a breaking operation during which the contacts of a mechanical

208 switching device reach sufficient distance to exclude re-ignition
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209 4 Type tests
210 4.1 General

211 Circuit-breakers according to IEC 62271-100 and contactors according to IEC 62271-106 do

212 not have dedicated inductive switching ratings. However, switching devices applied for this

213 purpose shall meet the requirements of this document.

214 For shunt reactor switching test of circuit-breakers, the rated insulation level values stated in

215 Tables 1, 2, 3 and 4 of IEC 62271-1:2017 are applicable with the exception of combined voltage

216 tests across the isolating distance (columns (6) and (8) in Table 3 and column (5) in Table 4).

217 The type tests are in addition to those specified in the relevant product standard, with the

218 exception of short-line faults, out-of-phase switching and capacitive current switching.

219 NOTE 1 The reason for this exception is the source-less nature of the shunt reactor load circuit.

220 NOTE 2 In some cases (high chopping overvoltage levels, or where a neutral reactor is present or in cases of shunt

221 reactors with isolated neutral), it can be necessary to specify an appropriate insulation level which is higher than the

222 rated values stated above.

223 Inductive current switching tests performed for a given current level and type of application may

224 be considered valid for another current rating and same type of application as detailed below:

225 a) for shunt reactor switching at rated voltages of 52 kV and above, tests at a particular current

226 level are to be considered valid for applications with a higher current level up to 150 % of

227 the tested current value;

228 b) for shunt reactor switching at rated voltages below 52 kV, type testing is required;

229 c) for high-voltage motor switching, type testing for stalled motor currents at 100 A and 300 A

230 is considered to cover stalled motor currents in the range 100 A to 300 A and up to the

231 current associated with the short-circuit current of test-duty T10 according to 7.107.2 of

232 IEC 62271-100:2021 for circuit-breakers and up to the rated operational current for

233 contactors.

234 With respect to a) the purpose of type testing is also to determine a re-ignition-free arcing time

235 window for controlled switching purposes (refer to IEC TR 62271-302) and caution should be

236 exercised when considering applications at higher currents than the tested values since the re-

237 ignition-free arcing window can increase at higher current.

238 Annex B of IEC 62271-100:2021 can be used with respect to tolerances on test quantities.

239 4.2 Miscellaneous provisions for inductive load switching tests

240 Subclause 7.102 of IEC 62271-100:2021 is applicable with the following addition:

241 High-voltage motor current and shunt reactor switching tests shall be performed at rated

242 auxiliary and control voltage or, where necessary, at maximum auxiliary and control voltage to

243 facilitate consistent control of the opening and closing operation according to 7.102.3.1 of

244 IEC 62271-100:2021.

245 For gas filled switching devices (including vacuum switching devices using gaseous media for

246 insulation), tests shall be performed at the rated functional pressure for interruption and

247 insulation, except for test-duty 4, where the pressure shall be the minimum functional pressure

248 for interruption and insulation.
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249 4.3 High-voltage motor current switching tests
250 4.3.1 Applicability

251 Subclause 4.3 is applicable to three-phase alternating current switching devices having rated

252 voltages above 1 kV and up to 17,5 kV, which are used for switching high-voltage motors. Tests

253 may be carried out at 50 Hz with a relative tolerance of 10 % or 60 Hz with a relative tolerance

254 of 10 %, both frequencies being considered equivalent.

255 Motor switching tests are applicable to all three-pole switching devices having rated voltages

256 equal to or less than 17,5 kV, which may be used for the switching of three-phase asynchronous

257 squirrel-cage or slip-ring motors. The switching device may be of a higher rated voltage than

258 the motor when connected to the motor through a stepdown transformer. However, the usual

259 application is a direct cable connection between switching device and motor. When tests are

260 required, they shall be made in accordance with 4.3.2 to 4.3.9.

261 When overvoltage limitation devices are mandatory for the tested equipment, the voltage

262 limiting devices may be included in the test circuit provided that the devices are an intrinsic part

263 of the equipment under test.

264 No limits to the overvoltages are given as the overvoltages are only relevant to the specific

265 application. Overvoltages between phases may be as significant as phase-to-earth

266 overvoltages.
267 4.3.2 General

268 The switching tests can be either field tests or laboratory tests. As regards overvoltages, the

269 switching of the current of a starting or stalled motor is usually the more severe operation.

270 Due to the non-linear behaviour of the motor iron core, it is not possible to exactly model the

271 switching of motor current using linear components in a test station. Tests using linear

272 components to simulate the motors can be considered to be more conservative than switching

273 actual motors.

274 For laboratory tests a standardized circuit simulating the stalled condition of a motor is specified

275 (refer to Figure 1). The parameters of this test circuit have been chosen to represent a relatively

276 severe case with respect to overvoltages and will cover the majority of service applications.

277 The laboratory tests are performed to prove the ability of a switching device to switch motors

278 and to establish its behaviour with respect to switching overvoltages , re-ignitions and current

279 chopping. These characteristics may serve as a basis for estimates of the switching device’s

280 performance in other motor circuits. Tests performed with the test currents defined in 4.3.3 and

281 4.3.4 demonstrate the capability of the switching device to switch high-voltage motors up to its

282 rated interrupting current.

283 For field tests, actual circuits are used with a supply system on the source side and a cable and

284 motor on the load side. There may be a transformer between the switching device and motor.

285 However, the results of such field tests are only valid for switching devices working in circuits

286 similar to those during the tests.

287 The apparatus under test includes the switching device with overvoltage protection devices if

288 they are normally fitted.

289 NOTE 1 Overvoltages can be produced when switching running motors. This condition is not represented by the

290 substitute circuit and is generally considered to be less severe than the stalled motor case.

291 NOTE 2 The starting period switching of a slip-ring motor is generally less severe due to the effect of the starting

292 resistor.
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Switchgear
Motor substitute
Source U under test
Bus representation Cable
L L R
b1 R
s p
IEC
293
Key
U rated voltage
earthing impedance impedance high enough to limit the phase-to-earth
fault current to less than the test current (can be
infinite)
L source side inductance
L  0,1 L, but prospective short-circuit current 
the rated short-circuit current of the tested switching
device
C supply side capacitance 0,03 µF to 0,05 µF for supply circuit A
1,5 µF to 2 µF for supply circuit B
L inductance of capacitors and
 2 µH
connections
Bus representation 5 m to 7 m in length spaced appropriate to the rated
voltage
L inductance of connections
 5 µH
Cable 100 m  10 m, screened, surge impedance 30  to
50 
L motor substitute inductance
load circuit 1: 100 A  10 A
load circuit 2: 300 A  30 A
R motor substitute resistance
cos φ  0,2
C motor substitute parallel frequency 10 kHz to 15 kHz
capacitance
R motor substitute parallel resistance amplitude factor 1,6 to 1,8
294
295 Figure 1 – Motor switching test circuit and summary of parameters
296 4.3.3 Characteristics of the supply circuits
297 4.3.3.1 General

298 A three-phase supply circuit shall be used. The tests shall be performed using two different

299 supply circuits A and B as specified in 4.3.3.2 and 4.3.3.3, respectively. Supply circuit A

300 represents the case of a motor connected directly to a transformer. Supply circuit B represents

301 the case where parallel cables are applied on the supply side.
302 4.3.3.2 Supply circuit A

303 The three-phase supply may be earthed through a high ohmic impedance so that the supply

304 voltage is defined with respect to earth. The impedance value shall be high enough to limit a

305 prospective line-to-earth fault current to a value below the test current.
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306 The source inductance L shall not be lower than that corresponding to the rated short-circuit

307 breaking current of the tested switching device. Its impedance shall also be not higher than

308 0,1 times the impedance of the inductance in the load circuit (see 4.3.4).
309 The su
...