prEN IEC 62146-1:2025
(Main)Capacitors for high-voltage alternating current circuit-breakers - Part 1: General and grading capacitors
Capacitors for high-voltage alternating current circuit-breakers - Part 1: General and grading capacitors
Spannungsausgleichskondensatoren für Hochspannungs-Wechselstrom-Leistungsschalter – Teil 1: Allgemeines und Kondensatoren mit Nennleistung
Condensateurs pour disjoncteurs à courant alternatif haute tension - Partie 1: Généralités et condensateurs de répartition
Kondenzatorji za izravnavo potenciala pri visokonapetostnih odklopnikih za izmenični tok - 1. del: Splošni in zaščitni kondenzatorji
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
01-julij-2025
Kondenzatorji za izravnavo potenciala pri visokonapetostnih odklopnikih za
izmenični tok - 1. del: Splošni in zaščitni kondenzatorji
Capacitors for high-voltage alternating current circuit-breakers - Part 1: General and
grading capacitors
Condensateurs pour disjoncteurs à courant alternatif haute tension - Partie 1:
Généralités et condensateurs de répartition
Ta slovenski standard je istoveten z: prEN IEC 62146-1:2025
ICS:
31.060.70 Močnostni kondenzatorji Power capacitors
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
33/720/CDV
COMMITTEE DRAFT FOR VOTE (CDV)
PROJECT NUMBER:
IEC 62146-1 ED2
DATE OF CIRCULATION: CLOSING DATE FOR VOTING:
2025-05-02 2025-07-25
SUPERSEDES DOCUMENTS:
33/712/CD, 33/717A/CC
IEC TC 33 : POWER CAPACITORS AND THEIR APPLICATIONS
SECRETARIAT: SECRETARY:
Italy Mr Stefano Zunino
OF INTEREST TO THE FOLLOWING COMMITTEES: HORIZONTAL FUNCTION(S):
SC 17A
ASPECTS CONCERNED:
Environment,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.
Recipients of this document are invited to submit, with their comments, notification of any relevant “In Some
Countries” clauses to be included should this proposal proceed. Recipients are reminded that the CDV stage is
the final stage for submitting ISC clauses. (SEE AC/22/2007 OR NEW GUIDANCE DOC).
TITLE:
Capacitors for high-voltage alternating current circuit-breakers - Part 1: General and grading
capacitors
PROPOSED STABILITY DATE: 2028
NOTE FROM TC/SC OFFICERS:
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.
2 IEC CDV 62146-1 ED2 © IEC 2025
1 CONTENTS
2 CONTENTS . 2
3 FOREWORD . 5
4 1 Scope . 7
5 2 Normative references . 7
6 3 Terms and definitions . 8
7 4 Abbreviations . 13
8 5 Service conditions . 14
9 5.1 General . 14
10 5.2 Normal service conditions . 14
11 5.2.1 Ambient temperature . 14
12 5.2.2 Altitude . 15
13 5.2.3 Mechanical stress and vibrations . 15
14 5.2.4 Additional service conditions for indoor and completely immersed
15 capacitor . 15
16 5.3 Special service conditions . 15
17 5.3.1 General . 15
18 5.3.2 Altitude correction. 15
19 5.3.3 Earthquakes . 16
20 6 Ratings . 16
21 6.1 Rated voltage (U ) . 16
cr
22 6.2 Rated insulation level . 17
23 6.3 Rated frequency (f ) . 18
r
24 7 Design and construction . 18
25 7.1 Capacitance tolerances . 18
26 7.2 Capacitor loss requirements. 18
27 7.3 Partial discharge level . 18
28 7.4 Angle of mounting . 18
29 7.5 Minimum withstand value of mechanical bending load . 19
30 7.5.1 Capacitors mounted on air insulated circuit-breaker . 19
31 7.5.2 Immersed capacitors . 19
32 7.6 Insulation fluids . 19
33 7.6.1 Liquid insulation . 19
34 7.6.2 Gas insulation . 20
35 7.7 Protection against corrosion . 20
36 7.8 Marking of the equipment . 20
37 7.9 Creepage distances for outdoor capacitors . 21
38 8 Type tests . 21
39 8.1 Information for identification of specimens . 21
40 8.2 Information to be included in type-test reports. 22
41 8.3 Test conditions . 22
42 8.4 Dielectric type tests . 22
43 8.4.1 General . 22
44 8.4.2 Switching impulse voltage test . 23
45 8.4.3 Lightning and chopped lightning impulse voltage tests . 24
46 8.5 Voltage test at low and high temperature . 24
IEC CDV 62146-1 ED2 © IEC 2025 3
47 8.5.1 Test procedure . 24
48 8.5.2 Capacitor reduced-scale model design . 25
49 8.6 Radio interference voltage (RIV) test . 25
50 8.7 Power frequency withstand voltage test . 25
51 8.8 Short-circuit discharge test . 26
52 8.9 Resonance frequency measurements . 26
53 8.10 Mechanical bending test . 26
54 8.11 Tightness test at different temperatures . 26
55 8.12 Tightness test to check gas ingress from a pressurised environment . 27
56 8.13 Vibration test . 27
57 9 Routine tests . 28
58 9.1 General . 28
59 9.2 Test conditions . 29
60 9.3 Capacitance and tan δ (loss angle) measurement at power frequency . 29
61 9.4 Power frequency withstand voltage test . 30
62 9.5 Partial discharge test . 30
63 9.6 Tightness test . 30
64 9.6.1 General . 30
65 9.6.2 Oil impregnated capacitor . 30
66 9.6.3 Tightness test for gas filled capacitors . 31
67 9.6.3.1Air insulated capacitors . 31
68 9.6.3.2Immersed capacitors . 31
69 9.7 Visual inspection and dimensional check . 32
70 10 Design test . 32
71 10.1 Aging test . 32
72 10.1.1 Test procedure . 32
73 10.1.2 Acceptance criteria . 33
74 11 Recommendations for transport, storage, erection, operation and maintenance . 33
75 11.1 General . 33
76 11.2 Conditions during transport, storage and installation . 33
77 11.3 Installation . 34
78 11.4 Unpacking and lifting . 34
79 11.5 Assembly . 34
80 11.5.1 Mounting . 34
81 11.5.2 Connections to metal parts . 34
82 11.5.3 Final installation inspection . 34
83 11.6 Operation . 34
84 11.7 Maintenance . 34
85 11.7.1 General . 34
86 11.7.2 Recommendation for the installation and maintenance . 35
87 12 Safety . 35
88 12.1 General . 35
89 12.2 Precautions by manufacturers . 35
90 12.3 Precautions by users . 35
91 12.4 National regulations . 35
92 13 Environmental aspects . 35
93 Annex A (informative) Corrosion: Information regarding service conditions and
94 recommended test requirements . 37
4 IEC CDV 62146-1 ED2 © IEC 2025
95 A.1 General . 37
96 A.2 Recommended test requirements . 37
97 Annex B (informative) Resonance frequency measurements . 38
98 B.1 General . 38
99 B.2 Time domain method . 38
100 B.2.1 Test procedure. 38
101 B.2.2 Measurement results. 39
102 B.3 Frequency domain method . 40
103 B.3.1 Test setup . 40
104 B.3.2 Measurement results. 41
105 Bibliography . 42
IEC CDV 62146-1 ED2 © IEC 2025 5
108 INTERNATIONAL ELECTROTECHNICAL COMMISSION
109 ____________
111 CAPACITORS FOR HIGH-VOLTAGE ALTERNATING CURRENT CIRCUIT-
112 BREAKERS
114 Part 1: General and grading capacitors
116 FOREWORD
117 1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
118 all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international
119 co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and
120 in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports,
121 Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). Their
122 preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with
123 may participate in this preparatory work. International, governmental and non-governmental organizations liaising
124 with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for
125 Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.
126 2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
127 consensus of opinion on the relevant subjects since each technical committee has representation from all
128 interested IEC National Committees.
129 3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
130 Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
131 Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
132 misinterpretation by any end user.
133 4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
134 transparently to the maximum extent possible in their national and regional publications. Any divergence between
135 any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.
136 5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
137 assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
138 services carried out by independent certification bodies.
139 6) All users should ensure that they have the latest edition of this publication.
140 7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
141 members of its technical committees and IEC National Committees for any personal injury, property damage or
142 other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
143 expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
144 Publications.
145 8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
146 indispensable for the correct application of this publication.
147 9) Attention to the possibility that the implementation of this document may involve the use of patents. IEC
148 Publication takes no position concerning the evidence, validity, or applicability of any claimed patent rights in
149 respect thereof. As of the date of publication of this document, IEC Publication had not received notice of patents,
150 which may be required to implement this document. However, implementers are cautioned that this may not
151 represent the latest information, which may be obtained from the patent database available at
152 https://patents.iec.ch [and/or] www.iso.org/patents. IEC Publication shall not be held responsible for identifying
153 any or all such patent rights.
154 IEC 62146-1 has been prepared by subcommittee JMT 17A: Joint Maintenance Team 17A, of
155 IEC technical committee TC 33: Power capacitors and their applications.
156 This second edition cancels and replaces the first edition published in 2016-06. This edition
157 constitutes a technical revision.
158 This edition includes the following significant technical changes with respect to the previous
159 edition:
160 a) Clause re-ordering and reworked sentences,
161 b) New type and special tests.
162 The text of this international standard is based on the following documents:
6 IEC CDV 62146-1 ED2 © IEC 2025
Draft Report on voting
33/XX/FDIS 33/XX/RVD
164 Full information on the voting for its approval can be found in the report on voting indicated in
165 the above table.
166 The language used for the development of this international standard is English.
167 This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
168 accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
169 at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
170 described in greater detail at www.iec.ch/publications.
171 A list of all parts in the IEC 62146 series, published under the general title Capacitors for high-
172 voltage alternating current circuit-breakers, can be found on the IEC website. The title of the
173 series was changed in 2022 by decision of TC 33, and the title of this standard, IEC 62146-1,
174 is modified accordingly.
175 The committee has decided that the contents of this document will remain unchanged until the
176 stability date indicated on the IEC website under webstore.iec.ch in the data related to the
177 specific document. At this date, the document will be replaced by a revised edition.
IEC CDV 62146-1 ED2 © IEC 2025 7
181 CAPACITORS FOR HIGH-VOLTAGE ALTERNATING CURRENT CIRCUIT-
182 BREAKERS
184 Part 1: General and grading capacitors
186 1 Scope
187 This part of the IEC 62146 series includes generalities of capacitors used on alternating current
188 circuit-breakers and introduce specifications for grading capacitors. Regarding grading
189 capacitors, their function is to control the voltage distribution across the individual interrupter
190 units of a multi-break circuit-breaker.
191 Capacitors can also be used in parallel to the interrupter unit on single break circuit-breakers
192 to modify the Transient Recovery Voltage (TRV). This TRV capacitor application is covered by
193 the IEC 62146-2:2023 standard.
194 Capacitors for high-voltage alternating circuit breakers is a sub-component for the circuit-
195 breaker and shall be specified in accordance with the circuit-breaker specifications according
196 to IEC 62271-1, IEC 62271-100, and if applicable to IEC 62271-203.
197 This standard applies to grading capacitors falling into one or both of the following categories
198 for:
199 − mounting on air-insulated circuit-breakers.
200 − mounting on enclosed circuit-breakers (for example immersed in insulating gas, in oil, etc.).
201 The testing for each of the above applications is in some cases different.
202 The object of this standard is:
203 − to define uniform rules regarding performances, testing and rating.
204 − to define specific safety rules.
205 − to provide a guidance for installation and operation.
206 NOTE CIGRE TB-368 presents a study about the operating environment of voltage grading capacitors applied to
207 high-voltage circuit-breakers (see [2]).
208 This standard does not apply to capacitors not directly associated with high-voltage alternating
209 current circuit-breakers.
210 2 Normative references
211 The following documents are referred to in the text in such a way that some or all of their content
212 constitutes requirements of this document. For dated references, only the edition cited applies.
213 For undated references, the latest edition of the referenced document (including any
214 amendments) applies.
215 IEC 60060-1, High-voltage test techniques – Part 1: General definitions and test requirements
216 IEC 60068-2-11, Environmental testing - Part 2-11: Tests - Test Ka: Salt mist
217 IEC 60068-2-17:2023, Environmental testing - Part 2-17: Tests - Test Q: Sealing
218 IEC 60068-2-42, Environmental testing - Part 2-42: Tests - Test Kc: Sulphur dioxide test for
219 contacts and connections
8 IEC CDV 62146-1 ED2 © IEC 2025
220 IEC 60071-1, Insulation co-ordination – Part 1: Definitions, principles and rules
221 IEC 60270:2000, High-voltage test techniques – Partial discharge measurements
222 IEC 60358-1, Coupling capacitors and capacitor dividers - Part 1: General rules
223 IEC 60567, Oil-filled electrical equipment – Sampling of gases and analysis of free and
224 dissolved gases – Guidance
225 IEC 60815 (all parts), Selection and dimensioning of high-voltage insulators intended for use in
226 polluted conditions
227 IEC 61462, Composite hollow insulators - Pressurized and unpressurized insulators for use in
228 electrical equipment with AC rated voltage greater than 1 000 V AC and D.C. voltage greater
229 than 1500V - Definitions, test methods, acceptance criteria and design recommendations
230 IEC 62146-2:2023, Capacitors for high‑voltage alternating current circuit‑breakers - Part 2: TRV
231 capacitors
232 IEC 62155:2003, Hollow pressurized and unpressurized ceramic and glass insulators for use in
233 electrical equipment with rated voltages greater than 1 000 V
234 IEC 62271-1, High-voltage switchgear and controlgear – Part 1: Common specifications
235 IEC 62271-100, High-voltage switchgear and controlgear – Part 100: Alternating current circuit-
236 breakers
237 IEC 62271-203, High-voltage switchgear and controlgear – Part 203: Gas-insulated metal-
238 enclosed switchgear for rated voltages above 52 kV
239 IEC 62271-205, High-voltage switchgear and controlgear - Part 205: Compact switchgear
240 assemblies for rated voltages above 52 kV
241 IEC 62271-300, High-voltage switchgear and controlgear – Part 300: Seismic qualification of
242 alternating current circuit-breakers
243 IEC Guide 109, Environmental aspects – Inclusion in electrotechnical product standards
244 CIGRE TB-368, Operating Environment of Voltage grading Capacitors applied to High Voltage
245 Circuit-Breakers
246 3 Terms and definitions
247 For the purposes of this document, the following terms and definitions apply.
248 ISO and IEC maintain terminology databases for use in standardization at the following
249 addresses:
250 • IEC Electropedia: available at https://www.electropedia.org/
251 • ISO Online browsing platform: available at https://www.iso.org/obp
IEC CDV 62146-1 ED2 © IEC 2025 9
253 3.1
254 arcing distance
255 shortest distance in the air external to the insulator between the metallic parts which normally
256 have the operating voltage between them.
257 [SOURCE: IEC 60050-471:2007, 471-01-01]
258 3.2
259 capacitor element
260 device consisting essentially of two electrodes separated by a dielectric.
261 [SOURCE: IEC 60050-436:1990, 436-01-03]
262 3.3
263 capacitor losses
264 active power dissipated in the capacitor.
265 [SOURCE: IEC 60050-436:1990, 436-04-10]
266 3.4
267 capacitor terminals
268 terminals intended for electrical and mechanical connection to the terminals of the interrupter
269 units of circuit-breakers.
270 3.5
271 capacitance tolerance
272 permissible difference between the actual capacitance and the rated capacitance under
273 specified conditions
274 Note 1 to entry: The actual capacitance should be measured at, or referred to, the temperature at which the rated
275 capacitance is defined.
276 [SOURCE: IEC 60050-436:1990, 436-04-01, modified by addition of Note to entry]
277 3.6
278 capacitor unit
279 assembly of one or more capacitor elements connected together and in the same container with
280 terminals brought out
281 Note 1 to entry: A common type of unit for grading capacitors has a cylindrical housing of insulating material and
282 metal end flanges which serve as terminals.
283 [SOURCE: IEC 60050-436:1990, 436-01-04, modified by addition of Note to entry]
284 3.7
285 completely immersed capacitor
286 capacitor, both ends of which are intended to be immersed in insulating media other than
287 ambient air (e.g. oil or gas)
288 [SOURCE: IEC 60050-471:2007, 471-02-04, modified (definition originally referred to "bushing"
289 instead of "capacitor")]
290 3.8
291 creepage distance
292 shortest distance along the surface of a solid insulating material between two conductive parts
293 Note 1 to entry: The surface of cement or any other non-insulating jointing material is not considered as forming
294 part of the creepage distance.
10 IEC CDV 62146-1 ED2 © IEC 2025
295 Note 2 to entry: If high-resistance coating is applied to parts of the insulating part of an insulator, such parts are
296 considered to be effective insulating surface and the distance over them is included in the creepage distance.
297 [SOURCE: IEC 60050-604:1987, 604-03-61, modified by addition of Notes to entry]
298 3.9
299 dielectric of a capacitor
300 insulating material between the electrodes of the capacitor element
301 Note 1 to entry: The major insulation generally consists of paper, plastic film, or a mixed of paper and plastic film
302 subsequently treated and impregnated with oil or gas at atmospheric pressure or higher.
303 3.10
304 external insulation
305 distance through the air and the surfaces in contact with the air of the grading capacitor that
306 are subjected to dielectric stresses.
307 Note 1 to entry: They are also subject to the effects of the atmospheric and other external conditions such as pollution,
308 humidity, ice, vermin, etc.
309 3.11
310 failure
311 termination of the ability of an item to perform a required function
312 Note 1 to entry: After failure the item has a fault.
313 Note 2 to entry: "Failure" is an event, as distinguished from "fault", which is a state.
314 Note 3 to entry: This concept as defined does not apply to items consisting of software only.
315 [SOURCE: IEC 60050-191:1990, 191-04-01]
316 3.12
317 flashover
318 electric breakdown between conductors in a gas or in a liquid or in a vacuum, at least partly
319 along the surface of solid insulation
320 [SOURCE: IEC 60050-212:2012, 212-11-47]
321 3.13
322 grading capacitor
323 capacitor for installation on high-voltage circuit-breakers to control the voltage distribution
324 across the individual interrupter unit
325 Note 1 to entry: The grading capacitors alone are accessories of the circuit-breaker
326 3.14
327 indoor capacitor
328 capacitor, both ends of which are intended to be in ambient air at atmospheric pressure but not
329 exposed to outdoor atmospheric conditions
330 [SOURCE: IEC 60050-471:2007, 471-02-05, modified (definition originally referred to "bushing"
331 instead of "capacitor")]
332 3.15
333 insulating envelope
334 insulator which is open from end to end, with or without sheds, including end fittings
335 Note 1 to entry An insulating envelope can be made from one or more permanently assembled insulating elements.
336 Note 2 to entry: The insulating envelope may be in ceramic, glass or analogous inorganic material, cast or moulded
337 resin, composite insulating material, in one piece or more pieces permanently assembled.
IEC CDV 62146-1 ED2 © IEC 2025 11
338 [SOURCE: IEC 60050-471:2007, 471-01-08, modified (definition originally referred to a hollow
339 insulator and Note 2 to entry has been added)]
340 3.16
341 outdoor capacitor
342 capacitor, both ends of which are intended to be in ambient air at atmospheric pressure, and
343 exposed to outdoor atmospheric conditions
344 [SOURCE: IEC 60050-471:2007, 471-02-07, modified (definition originally referred to "bushing"
345 instead of "capacitor")]
346 3.17
347 internal insulation
348 internal solid, liquid or gaseous parts of the insulation of the grading capacitor which are
349 protected from the effects of atmospheric conditions
350 Note 1 to entry: The parts are also protected from other external conditions such as pollution, humidity, ice, vermin,
351 etc.
352 3.18
353 major failure (of a capacitor)
354 failure of a capacitor which causes the cessation of its fundamental function.
355 Note 1 to entry: A major failure will result in a mandatory removal from service within 30 min for unscheduled
356 maintenance.
357 3.19
358 mechanical stress
359 any mechanical stress applied to the insulating envelope and to the terminals of the capacitor
360 Note 1 to entry: It is a function of the following main forces:
361 – forces on the terminals due to the circuit-breaker connection;
362 – forces due to the wind and ice;
363 – seismic forces;
364 – forces due to the operating conditions, opening and closing, of the circuit- breaker;
365 – thermal forces due to the ambient medium conditions;
366 – forces due to the transportation of the circuit-breaker or capacitors.
367 3.20
368 minor failure (of a capacitor)
369 any failure of a capacitor which does not cause a major failure of the capacitor
370 3.21
371 puncture
372 disruptive discharge occurring through a solid insulation material, producing a path of
373 permanent damage
374 Note 1 to entry: The term puncture is also used as a synonym for electrical breakdown in solids.
375 [SOURCE: IEC 60050-212:2010, 212-11-49]
376 3.22
377 rated capacitance of a capacitor
378 C
r
379 capacitance value for which the capacitor has been designed
12 IEC CDV 62146-1 ED2 © IEC 2025
380 3.23
381 rated chopped lightning impulse withstand voltage
382 required peak value of the chopped lightning impulse withstand voltage which characterises the
383 insulation of a capacitor as regards the withstand tests
384 Note 1 to entry: The definitions and the standard parameters applicable to chopped impulses are specified in
385 IEC 60060-1.
386 3.24
387 rated frequency of a capacitor
388 f
r
389 frequency for which the capacitor has been designed
390 [SOURCE: IEC 60050-436:1990, 436-01-14, modified by addition of symbol]
391 3.25
392 rated insulation level
393 test voltages, under specified conditions, that the insulation is designed to withstand
394 Note 1 to entry: These test voltages can be for instance:
395 a) rated chopped and lightning impulse and short duration power frequency withstand voltages for capacitors
396 installed on circuit-breaker with rated voltage lower than 300 kV.
397 b) rated switching, lightning, chopped impulse and short duration power frequency withstand voltages for
398 capacitors installed on circuit-breaker with rated voltage equal to or greater than 300 kV.
399 Note 2 to entry: The rated insulation levels of the capacitor should be equal to or higher than the relevant
400 requirements for the circuit-breaker interrupting unit.
401 [SOURCE: IEC 60050-421:1990, 421-09-02, modified Note to entry]
402 3.26
403 rated lightning impulse withstand voltage
404 U
C LI
405 required peak value of the lightning impulse withstand voltage which characterises the
406 insulation of an equipment as regards the withstand tests
407 Note 1 to entry: The standard lightning impulse has a front time of 1,2 µs and a time-to-half-value of 50 µs as
408 specified in IEC 60060-1.
409 3.27
410 rated short duration power frequency withstand voltage
411 U
C PF
412 required r.m.s. value of sinusoidal power frequency voltage that the equipment withstands
413 during tests made under specified conditions and for a duration of 1 min unless otherwise
414 specified
415 3.28
416 rated switching impulse withstand voltage
417 U
C SI
418 required peak value of the switching impulse withstand voltage which characterises the
419 insulation of an equipment as regards the withstand tests
420 Note 1 to entry: The standard switching impulse has a time-to-crest of 250 µs and a time-to-half-value of 2500 µs
421 as specified in IEC 60060-1.
422 3.29
423 rated temperature category of a capacitor
424 range of temperature of the ambient air or other medium in which the capacitor is immersed
425 during the service life and for which it has been designed.
IEC CDV 62146-1 ED2 © IEC 2025 13
426 3.30
427 rated voltage of a capacitor
428 U
cr
429 r.m.s. value of the alternating voltage assigned to the capacitor for identification and at which
430 the capacitor is designed to operate continuously.
431 3.31
432 rated voltage of circuit-breaker
433 U
r
434 indicates the upper limit of the highest voltage of systems for which the circuit-breaker is
435 intended
436 Note 1 to entry: See IEC 62271-1.
437 Note 2 to entry: U used in IEC 62271 series corresponds to U presented in IEC 60071.
r m
438 3.32
439 resonance frequency
440 frequency for which the reactance of the intrinsic capacitance of the capacitor is equal to the
441 reactance of the self-inductance of the capacitor.
442 3.33
443 sample
444 device for testing
445 Note 1 to entry: Examples of such devices are a complete small capacitor, or the housing of a grading capacitor with
446 metal end flanges filled with impregnating fluid.
447 3.34
448 tangent of the loss angle of a capacitor
449 tan δ
450 ratio between the equivalent series resistance and the capacitive reactance of a capacitor at
451 specified sinusoidal alternating voltage and frequency.
452 [SOURCE: IEC 60050-436:1990, 436-04-11]
453 3.35
454 voltage grading factor of a circuit-breaker
455 (F )
VG
456 value that defines the standard values of rated voltages for the grading capacitor.
457 Note 1 to entry: This factor is the ratio between the actual maximum power frequency voltage fraction across one
458 interrupter unit of a multi-break circuit-breaker and the calculated linear power frequency voltage distribution per
459 interrupting unit.
460 Note 2 to entry: It is dependent on the circuit-breaker design, of the capacitance value of the grading capacitor and
461 its tolerance and of the safety margin.
463 4 Abbreviations
464 TRV Transient Recovery Voltage
465 C Rated capacitance of a capacitor
r
466 f Rated frequency of a capacitor
r
14 IEC CDV 62146-1 ED2 © IEC 2025
467 U Rated voltage of a capacitor
cr
468 U Rated voltage of circuit-breaker
r
469 tan δ Tangent of the loss angle of a capacitor
470 F Voltage grading factor of a circuit-breaker
VG
471 U Rated short-duration power frequency withstand voltage for the grading capacitor
C PF
472 U Rated short-duration power frequency withstand voltage across the open circuit-breaker
PF
473 U Rated lightning impulse withstand voltage for the grading capacitor
C LI
474 U Combined lightning and power frequency withstand voltage for the circuit-
(LI + PF)
475 breaker
476 U Rated switching impulse withstand voltage for the grading capacitor
C SI
477 U Combined switching and power frequency withstand voltage for the circuit-
(SI + PF)
478 breaker
479 U Chopped lightning impulse voltage for the grading capacitor
C LIC
480 RIV Radio interference voltage
481 ESR Equivalent series resistance
483 5 Service conditions
484 5.1 General
485 The capacitors mentioned in this standard are intended to be installed on circuit-breakers, for
486 which the normal and special service conditions are described in IEC 62271-1.
487 Additional service conditions specific to the capacitors are given in 5.2.3.
488 5.2 Normal service conditions
489 5.2.1 Ambient temperature
490 For outdoor application the normal service conditions of the grading capacitor are given in
491 IEC 62271-1.
492 For an immersed capacitor, the temperature around the capacitor can be higher than the
493 ambient air around the breaker. The preferred values of maximum surrounding temperature to
494 be specified should be: 60 °C, 70 °C, 80 °C.
495 The internal operating temperature of the capacitor is higher than the maximum temperature
496 around the capacitor and should be considered by the capacitor manufacturer.
IEC CDV 62146-1 ED2 © IEC 2025 15
497 5.2.2 Altitude
498 The altitude does not exceed 1 000 m.
499 5.2.3 Mechanical stress and vibrations
500 Mechanical stress and vibrations due to:
501 − forces due to wind and ice are according to IEC 62271-1;
502 − forces on the terminals due to the circuit-breaker connection which value shall be defined by
503 agreement between purchaser and capacitor manufacturer;
504 − forces due to the operations consequent to vibrations, such as opening and closing, of the
505 circuit-breaker.
506 Vibrations due to earthquakes are not considered for normal service conditions.
507 5.2.4 Additional service conditions for indoor and completely immersed capacitor
508 The completely immersed capacitors are subjected to the following other conditions:
509 − the influence of the insulating gas pressure;
510 − the resistance of the capacitor materials against the decomposition products of the insulating
511 gas.
512 5.3 Special service conditions
513 5.3.1 General
514 The special service conditions are given in IEC 62271-1; if they are required, the purchaser will
515 specify it to the capacitor manufacturer.
516 5.3.2 Altitude correction
517 The coordination withstand voltages are considered valid up to an altitude of 1 000 m. To
518 consider the reduced withstand capability of the air at an installation site with an altitude above
519 1 000 m, the required type test insulation withstand level of external insulation at standard
520 reference atmospheric conditions shall be determined by multiplying the withstand voltage
521 required on site by an altitude correction factor K . The correction factor shall not be applied
a
522 for routine tests, because a routine test validates the quality of the internal insulation only.
523 For AC applications, the altitude correction factor shall be determined in accordance with
524 IEC 60071-2:2023, clause 7.2.2, using Equation H.13 from IEC 60071-2:2023, Annex H, clause
525 H3.4, as follows:
H−1000
( )
m
526 K = e
a
527 where
528 H is the altitude above sea level (in metres);
529 m is as follows:
530 m = 1,0 for co-ordination lightning impulse withstand voltages;
531 m = 1,0 for power-frequency withstand voltages in case of wet tests;
532 m is in accordance with Figure 1 for co-ordination switching impulse withstand voltages.
534 NOTE To determine the value of m for the switching impulse shown in Figure 1, use the switching impulse value
535 applicable to normal service conditions.
16 IEC CDV 62146-1 ED2 © IEC 2025
537 Figure 1 – Factor m for the switching impulse withstand test
538 To verify the withstand voltages corrected for altitude, the arcing distance of the capacitor needs
539 to be increased. If increasing the arcing distance is based on a verified arcing distance of a
540 similar product, it can be considered valid without further testing.
541 If the withstand voltages corrected for altitude cannot be validated by an increased arcing
542 distance of a similar product, external insulation shall be tested in accordance with IEC 60071-
543 2:2023, clause 8.3.7.
544 NOTE It is considered that the altitude does not affect the internal insulation.
545 5.3.3 Earthquakes
546 For the earthquake stress the grading capacitors must be considered as accessories of the
547 circuit-breaker and in this way, they must satisfy the seismic qualification rules according to
548 IEC 62271-300.
549 NOTE Assuming that the mechanical stresses on circuit-breakers due to seismic a
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.
Loading comments...