EN 62146-1:2014
(Main)Grading capacitors for high-voltage alternating current circuit-breakers - Part 1: General
Grading capacitors for high-voltage alternating current circuit-breakers - Part 1: General
IEC 62146-1:2013 is applicable to grading capacitors used on circuit-breakers. Their function is to control the voltage distribution across the individual interrupter units of a multi-break circuit-breaker. Grading capacitors can also be used in parallel to the interrupter unit on single break circuit-breakers to modify the Transient Recovery Voltage (TRV). The grading capacitor is a sub-component for the circuit-breaker and shall be specified in accordance with the circuit-breaker specifications. This standard applies to grading capacitors falling into one or both of the following categories for: - mounting on air-insulated circuit-breakers; - mounting on enclosed circuit-breakers (for example immersed in SF6, in oil, etc.). The testing for each of the above applications is in some cases different. The object of this standard is: - to define uniform rules regarding performances, testing and rating; - to define specific safety rules; - to provide a guidance for installation and operation. Keywords: grading capacitors, circuit-breakers
Steuerkondensatoren für Hochspannungs-Wechselstrom-Leistungsschalter - Teil 1: Allgemeines
Condensateurs de répartition pour disjoncteurs à courant alternatif haute tension - Partie 1: Généralités
La CEI 62146-1:2013 s'applique aux condensateurs de répartition utilisés sur les disjoncteurs. Ces condensateurs ont pour fonction de contrôler la répartition de la tension entre chaque interrupteur d'un disjoncteur à coupure multiple. Les condensateurs de répartition peuvent également être utilisés parallèlement à l'interrupteur de disjoncteurs à coupure unique afin de modifier la tension transitoire de rétablissement (TRV - Transient Recovery Voltage). Le condensateur de répartition est un sous-composant du disjoncteur et il est spécifié conformément aux spécifications des disjoncteurs. La présente norme s'applique aux condensateurs de répartition à l'huile, à gaz et céramique relevant de l'une ou des deux catégories suivantes pour: - l'installation sur les disjoncteurs isolés dans l'air; - l'installation sur des disjoncteurs protégés (par exemple, immergés dans du gaz SF6, dans l'huile, etc.). L'essai applicable à chacune des applications susmentionnées est différent dans certains cas. La présente norme a pour objet de: - définir des règles uniformes concernant les performances, essais et caractéristiques assignées; - définir des règles de sécurité spécifiques; - fournir un guide d'installation et d'exploitation. Mots clés: Le condensateur de repartition, disjoncteurs
Kondenzatorji za izravnavo potenciala pri visokonapetostnih odklopnikih za izmenični tok - 1. del: Splošno (IEC 62146-1:2013)
Serija standardov EN-IEC 62146-1 se uporablja za kondenzatorje za izravnavo potenciala, ki se uporabljajo pri odklopnikih. Njihova naloga je, da nadzorujejo napetostne razdelilne sisteme v posameznih prekinitvenih enotah večprekinitvenega odklopnika. Kondenzatorji za izravnavo potenciala se lahko uporabijo tudi vzporedno s prekinitveno enoto enoprekinitvenih odklopnikov za izravnavo tranzientne povrnitve napetosti (TRV). Kondenzator za izravnavo potenciala je sestavni del odklopnika in se določi v skladu s specifikacijami odklopnika. Ta standard se uporablja za kondenzatorje za izravnavo potenciala, ki spadajo v eno ali v obe kategoriji za: – nameščanje na zračno izolirane odklopnike; – nameščanje na izolirane odklopnike (npr. potopljeni v SF6, olje itd.). Preskušanje za vsako zgoraj navedeno uporabo se v nekaterih primerih razlikuje. Namen tega standarda je: – določitev enotnih pravil glede lastnosti zmogljivosti, preskušanja in ocenjevanja; – določitev posebnih varnostnih pravil; – pomoč pri namestitvi in delovanju.
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
01-maj-2014
.RQGHQ]DWRUML]DL]UDYQDYRSRWHQFLDODSULYLVRNRQDSHWRVWQLKRGNORSQLNLK]D
L]PHQLþQLWRNGHO 6SORãQR ,(&
Grading capacitors for high-voltage alternating current circuit-breakers - Part 1: General
/
Condensateurs de répartition pour disjoncteurs à courant alternatif haute tension - Partie
1: Généralités
Ta slovenski standard je istoveten z: EN 62146-1:2014
ICS:
31.060.70 0RþQRVWQLNRQGHQ]DWRUML Power capacitors
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
EUROPEAN STANDARD
EN 62146-1
NORME EUROPÉENNE
March 2014
EUROPÄISCHE NORM
ICS 31.060.01; 31.060.70
English version
Grading capacitors for high-voltage alternating current circuit-breakers -
Part 1: General
(IEC 62146-1:2013)
Condensateurs de répartition pour Spannungsausgleichskondensatoren für
disjoncteurs à courant alternatif haute Hochspannungs-Wechselstrom-
tension - Leistungsschalter -
Partie 1: Généralités Teiln 1: Allgemeines
(CEI 62146-1:2013) (IEC 62146-1:2013)
This European Standard was approved by CENELEC on 2013-10-30. CENELEC members are bound to comply
with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard
the status of a national standard without any alteration.
Up-to-date lists and bibliographical references concerning such national standards may be obtained on
application to the CEN-CENELEC Management Centre or to any CENELEC member.
This European Standard exists in three official versions (English, French, German). A version in any other
language made by translation under the responsibility of a CENELEC member into its own language and notified
to the CEN-CENELEC Management Centre has the same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus,
the Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany,
Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland,
Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom.
CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Avenue Marnix 17, B - 1000 Brussels
© 2014 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 62146-1:2014 E
Foreword
The text of document 33/535/FDIS, future edition 1 of IEC 62146-1, prepared by IEC/TC 33, "Power
capacitors and their applications" was submitted to the IEC-CENELEC parallel vote and approved by
CENELEC as EN 62146-1:2014.
The following dates are fixed:
(dop) 2014-09-14
• latest date by which the document has
to be implemented at national level by
publication of an identical national
standard or by endorsement
• latest date by which the national (dow) 2016-10-30
standards conflicting with the
document have to be withdrawn
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC [and/or CEN] shall not be held responsible for identifying any or all such patent
rights.
Endorsement notice
The text of the International Standard IEC 62146-1:2013 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following notes have to be added for the standards indicated:
IEC 60068-2-11 NOTE Harmonized as EN 60068-2-11
IEC 60068-2-42 NOTE Harmonized in EN 60068-2-42
- 3 - EN 62146-1:2014
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
NOTE When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD
applies.
Publication Year Title EN/HD Year
CISPR 18-2 1986 Radio interference characteristics of overhead - -
power lines and high-voltage equipment - Part
2: Methods of measurement and procedure
for determining limits
IEC Guide 109 Environmental aspects - Inclusion in - -
electrotechnical product standards
IEC 60050 (Series) International Electrotechnical Vocabulary - -
(IEV)
IEC 60060-1 2010 High-voltage test techniques - Part 1: General EN 60060-1 2010
definitions and test requirements
IEC 60068-2-17 1994 Environmental testing - Part 2: Tests - Test Q: EN 60068-2-17 1994
Sealing
IEC 60071-1 2006 Insulation co-ordination - Part 1: Definitions, EN 60071-1 2006
principles and rules
IEC 60270 2000 High-voltage test techniques - Partial EN 60270 2001
+ corr. October 2001 discharge measurements
IEC 60376 2005 Specification of technical grade sulfur EN 60376 2005
hexafluoride (SF6) for use in electrical
equipment
IEC 60507 1991 Artificial pollution tests on high-voltage EN 60507 1993
insulators to be used on a.c. systems
IEC 60567 2011 Oil-filled electrical equipment - Sampling of EN 60567 2011
gases and analysis of free and dissolved
gases - Guidance
IEC 60721-1 1990 Classification of environmental conditions - EN 60721-1 1995
+ A1 1992 Part 1: Environmental parameters and their - -
1)
+ A2 1995 severities + A2 1995
IEC/TS 60815 Selection and dimensioning of high-voltage - -
(series) insulators intended for use in polluted
conditions
IEC 61462 2007 Composite hollow insulators - Pressurized and EN 61462 2007
unpressurized insulators for use in electrical
equipment with rated voltage greater than 1
000 V - Definitions, test methods, acceptance
criteria and design recommendations
1)
EN 60721-1 includes A1 to IEC 60721-1.
IEC 62155 (mod) 2003 Hollow pressurized and unpressurized EN 62155 2003
ceramic and glass insulators for use in
electrical equipment with rated voltages
greater than 1 000 V
IEC 62271-1 2007 High-voltage switchgear and controlgear - EN 62271-1 2008
Part 1: Common specifications
IEC 62271-100 2008 High-voltage switchgear and controlgear - EN 62271-100 2009
Part 100: Alternating current circuit-breakers
2)
IEC 62271-203 2003 High-voltage switchgear and controlgear - EN 62271-203 2004
Part 203: Gas-insulated metal-enclosed
switchgear for rated voltages above 52 kV
IEC/TR 62271-300 2006 High-voltage switchgear and controlgear - - -
Part 300: Seismic qualification of alternating
current circuit-breakers
2)
EN 62271-203 is superseded by EN 62271-203:2012, which is based on IEC 62271-203:2011.
IEC 62146-1 ®
Edition 1.0 2013-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Grading capacitors for high-voltage alternating current circuit-breakers –
Part 1: General
Condensateurs de répartition pour disjoncteurs à courant alternatif haute
tension –
Partie 1: Généralités
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX W
ICS 31.060.01; 31.060.70 ISBN 978-2-8322-1109-0
– 2 – 62146-1 © IEC:2013
CONTENTS
FOREWORD . 4
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 7
4 Abbreviations . 12
5 Normal and special service conditions . 13
5.1 General . 13
5.2 Normal service conditions . 13
5.2.1 Ambient temperature . 13
5.2.2 Mechanical stress and vibrations . 13
5.2.3 Additional service conditions for indoor and completely immersed
grading capacitor . 13
5.3 Special service conditions . 13
5.3.1 General . 13
5.3.2 Earthquakes . 13
6 Ratings . 14
6.1 Rated voltage (U ) . 14
cr
6.2 Rated insulation level . 14
6.3 Rated frequency (f ) . 15
r
7 Design and construction . 15
7.1 Capacitance tolerances . 15
7.2 Capacitor loss requirements . 15
7.3 Angle of mounting . 15
7.4 Minimum withstand value of mechanical bending load . 15
7.5 Requirements for impregnation medium in capacitor . 16
7.6 Protection against corrosion . 16
7.7 Nameplates . 16
7.8 Creepage distances for outdoor insulators . 16
7.9 Tightness . 16
7.9.1 Liquid tightness . 16
7.9.2 Gas tightness for grading capacitors immersed in gas . 17
8 Type tests . 17
8.1 Information for identification of specimens . 17
8.2 Information to be included in type-test reports . 17
8.3 Test conditions . 18
8.4 Dielectric tests . 18
8.4.1 General . 18
8.4.2 Capacitance measurement at power frequency . 19
8.4.3 Measurement of the tangent of the loss angle (tanδ) . 20
8.4.4 Partial discharge test . 20
8.4.5 Switching impulse voltage test . 21
8.4.6 Lightning and chopped impulse voltage test. 21
8.4.7 Power frequency voltage test. . 22
8.5 Voltage test at low and high temperature . 22
8.6 Radio interference voltage (RIV) test . 23
8.7 Resonance frequency measurements . 23
62146-1 © IEC:2013 – 3 –
8.8 Mechanical bending test . 23
8.9 Tightness test at different temperatures . 23
8.10 Tightness test to check gas ingress from a pressurised environment . 24
8.11 Vibration test . 24
9 Routine tests . 25
9.1 General . 25
9.2 Test conditions . 25
9.3 Capacitance and loss angle measurement at power frequency . 25
9.4 Power frequency voltage test . 26
9.5 Partial discharge test . 26
9.6 Tightness test . 26
9.6.1 General . 26
9.6.2 Oil impregnated capacitor . 26
9.6.3 Tightness test for gas filled grading capacitors . 26
9.7 Visual inspection and dimensional check . 27
10 Recommendations for transport, storage, erection, operation and maintenance . 27
10.1 General . 27
10.2 Conditions during transport, storage and installation . 27
10.3 Installation. 27
10.4 Unpacking and lifting . 28
10.5 Assembly . 28
10.5.1 Mounting . 28
10.5.2 Connections to metal parts . 28
10.5.3 Final installation inspection . 28
10.6 Operation . 28
10.7 Maintenance . 28
10.7.1 General . 28
10.7.2 Recommendation for the installation and maintenance . 28
10.7.3 Recommendations for the user . 29
10.7.4 Failure report . 29
11 Safety . 30
11.1 General . 30
11.2 Precautions by manufacturers . 30
11.3 Precautions by users . 31
11.4 National regulations . 31
12 Environmental aspects . 31
Annex A (informative) Corrosion: Information regarding service conditions and
recommended test requirements . 32
Annex B (informative) Resonance frequency measurements . 33
Bibliography . 34
Figure 1 – Dielectric type tests . 19
Figure 2 – Dielectric routine test . 25
Figure B.1 – Example of resonance frequency measurement recording (see 8.7) . 33
Table 1 – Partial discharge test voltages and permissible levels . 21
– 4 – 62146-1 © IEC:2013
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
GRADING CAPACITORS FOR HIGH-VOLTAGE
ALTERNATING CURRENT CIRCUIT-BREAKERS –
Part 1: General
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 62146-1 has been prepared by IEC technical committee 33: Power
capacitors and their applications.
The text of this standard is based on the following documents:
FDIS Report on voting
33/535/FDIS 33/541/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts in the IEC 62146 series, published under the general title Grading
capacitators for high-voltage alternating current circuit-breakers, can be found on the IEC
website.
62146-1 © IEC:2013 – 5 –
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
– 6 – 62146-1 © IEC:2013
GRADING CAPACITORS FOR HIGH-VOLTAGE
ALTERNATING CURRENT CIRCUIT-BREAKERS –
Part 1: General
1 Scope
This part of the IEC 62146 series is applicable to grading capacitors used on circuit-breakers.
Their function is to control the voltage distribution across the individual interrupter units of a
multi-break circuit-breaker.
Grading capacitors can also be used in parallel to the interrupter unit on single break circuit-
breakers to modify the Transient Recovery Voltage (TRV).
The grading capacitor is a sub-component for the circuit-breaker and shall be specified in
accordance with the circuit-breaker specifications.
This standard applies to grading capacitors falling into one or both of the following categories
for:
– mounting on air-insulated circuit-breakers;
– mounting on enclosed circuit-breakers (for example immersed in SF , in oil, etc.).
The testing for each of the above applications is in some cases different.
The object of this standard is:
– to define uniform rules regarding performances, testing and rating;
– to define specific safety rules;
– to provide a guidance for installation and operation.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and
are indispensable for its application. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 60050 (all parts), International electrotechnical vocabulary (available at
http://www.electropedia.org)
IEC 60060-1:2010, High-voltage test techniques – Part 1: General definitions and test
requirements
IEC 60068-2-17:1994, Official version in Russian – Basic environmental testing procedures –
Part 2-17: Tests – Test Q: Sealing
IEC 60071-1:2006, Insulation co-ordination – Part 1: Definitions, principles and rules
IEC 60270:2000, High-voltage test techniques – Partial discharge measurements
62146-1 © IEC:2013 – 7 –
IEC 60376:2005, Specification of technical grade sulfur hexafluoride (SF ) for use in electrical
equipment
IEC 60507-1:1991, Artificial pollution tests on high-voltage insulators to be used on a.c.
systems
IEC 60567:2011, Oil-filled electrical equipment – Sampling of gases and analysis of free and
dissolved gases – Guidance
IEC 60721-1:2002, Classification of environmental conditions – Part 1: Environmental
parameters and their severities
IEC 60815 (all parts), Selection and dimensioning of high-voltage insulators intended for use
in polluted conditions
IEC 61462:2007, Composite hollow insulators – Pressurized and unpressurized insulators for
use in electrical equipment with rated voltage greater than 1 000 V – Definitions, test
methods, acceptance criteria and design recommendations
IEC 62155:2003, Hollow pressurized and unpressurized ceramic and glass insulators for use
in electrical equipment with rated voltages greater than 1 000 V
IEC 62271-1:2007, High-voltage switchgear and controlgear – Part 1: Common specifications
IEC 62271-100:2008, High-voltage switchgear and controlgear – Part 100: Alternating current
circuit-breakers
IEC 62271-203:2003, High-voltage switchgear and controlgear – Part 203: Gas-insulated
metal-enclosed switchgear for rated voltages above 52 kV
IEC 62271-300:2006, High-voltage switchgear and controlgear – Part 300: Seismic
qualification of alternating current circuit-breakers
IEC Guide 109, Environmental aspects – Inclusion in electrotechnical product standards
CISPR 18-2:1986, Radio interference characteristics of overhead power lines and high-
voltage equipment – Part 2: Methods of measurement and procedure for determining limits
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
arcing distance
shortest distance in the air external to the insulator between the metallic parts which normally
have the operating voltage between them
[SOURCE: IEC 60050-471:2007, 471-01-01]
3.2
capacitor element
device consisting essentially of two electrodes separated by a dielectric
[SOURCE: IEC 60050-436:1990, 436-01-03]
– 8 – 62146-1 © IEC:2013
3.3
capacitor losses
active power dissipated in the capacitor
[SOURCE: IEC 60050-436:1990, 436-04-10]
3.4
capacitor terminals
terminals intended for electrical and mechanical connection to the terminals of the interrupter
units of circuit-breakers
3.5
capacitance tolerance
permissible difference between the actual capacitance and the rated capacitance under
specified conditions
Note 1 to entry: The actual capacitance should be measured at, or referred to, the temperature at which the rated
capacitance is defined.
[SOURCE: IEC 60050-436:1990, 436-04-01, modified by addition of Note to entry]
3.6
capacitor unit
assembly of one or more capacitor elements in the same container with terminals brought out
Note 1 to entry: A common type of unit for grading capacitors has a cylindrical housing of insulating material and
metal end flanges which serve as terminals.
[SOURCE: IEC 60050-436:1990, 436-01-04, modified by addition of Note to entry]
3.7
completely immersed capacitor
capacitor, both ends of which are intended to be immersed in insulating media other than
ambient air (e.g. oil or gas)
[SOURCE: IEC 60050-471:2007, 471-02-04, modified (definition originally referred to
"bushing" instead of "capacitor")]
3.8
creepage distance
shortest distance along the surface of a solid insulating material between two conductive
parts
Note 1 to entry: The surface of cement or any other non-insulating jointing material is not considered as forming
part of the creepage distance.
Note 2 to entry: If high-resistance coating is applied to parts of the insulating part of an insulator, such parts are
considered to be effective insulating surface and the distance over them is included in the creepage distance.
[SOURCE: IEC 60050-604:1987, 604-03-61, modified by addition of Notes to entry]
3.9
dielectric of a capacitor
insulating material between the electrodes of the capacitor element
Note 1 to entry: The major insulation generally consists of paper, plastic film, or a mixed of paper and plastic film
subsequently treated and impregnated with oil or gas at atmospheric pressure or higher.
62146-1 © IEC:2013 – 9 –
3.10
external insulation
distance in air and the surfaces in contact with open air of insulation of the grading capacitor
which are subject to dielectric stresses
Note 1 to entry: They are also subject to to the effects of the atmospheric and other external conditions such as
pollution, humidity, ice, vermin, etc.
3.11
failure
termination of the ability of an item to perform a required function
Note 1 to entry: After failure the item has a fault.
Note 2 to entry: "Failure" is an event, as distinguished from "fault", which is a state.
Note 3 to entry: This concept as defined does not apply to items consisting of software only.
[SOURCE: IEC 60050-191:1990, 191-04-01]
3.12
flashover
electric breakdown between conductors in a gas or in a liquid or in a vacuum, at least partly
along the surface of solid insulation
[SOURCE: IEC 60050-212:2012, 212-11-47]
3.13
grading capacitor
capacitor for installation on high-voltage circuit-breakers to control the voltage distribution
across the individual interrupter unit
Note 1 to entry: The grading capacitors alone are accessories of the circuit-breaker
3.14
indoor capacitor
capacitor, both ends of which are intended to be in ambient air at atmospheric pressure but
not exposed to outdoor atmospheric conditions
[SOURCE: IEC 60050-471:2007, 471-02-05, modified (definition originally referred to
"bushing" instead of "capacitor")]
3.15
insulating envelope
insulator which is open from end to end, with or without sheds, including end fittings
Note 1 to entry An insulating envelope can be made from one or more permanently assembled insulating
elements.
Note 2 to entry: The insulating envelope may be in ceramic, glass or analogous inorganic material, cast or
moulded resin, composite insulating material, in one piece or more pieces permanently assembled.
[SOURCE: IEC 60050-471:2007, 471-01-08, modified (definition originally referred to a hollow
insulator and Note 2 to entry has been added)]
3.16
outdoor capacitor
capacitor, both ends of which are intended to be in ambient air at atmospheric pressure, and
exposed to outdoor atmospheric conditions
– 10 – 62146-1 © IEC:2013
[SOURCE: IEC 60050-471:2007, 471-02-07, modified (definition originally referred to
"bushing" instead of "capacitor")]
3.17
internal insulation
internal solid, liquid or gaseous parts of the insulation of the grading capacitor which are
protected from the effects of atmospheric conditions
Note 1 to entry: The parts are also protected from other external conditions such as pollution, humidity, ice, vermin,
etc.
3.18
major failure (of a grading capacitor)
failure of a grading capacitor which causes the cessation of its fundamental function.
Note 1 to entry: A major failure will result in a mandatory removal from service within 30 min for unscheduled
maintenance.
3.19
mechanical stress
any mechanical stress applied to the insulating envelope and to the terminals of the grading
capacitor
Note 1 to entry: It is a function of the following main forces:
– forces on the terminals due to the circuit-breaker connection;
– forces due to the wind and ice;
– seismic forces;
– forces due to the operating conditions, opening and closing, of the circuit- breaker;
– thermal forces due to the ambient medium conditions;
– forces due to the transportation of the circuit-breaker or grading capacitors.
3.20
minor failure (of a grading capacitor)
any failure of a grading capacitor which does not cause a major failure of the grading
capacitor
3.21
puncture
disruptive discharge occurring through a solid insulation material, producing a path of
permanent damage
Note 1 to entry: The term puncture is also used as a synonym for electrical breakdown in solids.
[SOURCE: IEC 60050-212:2010, 212-11-49]
3.22
rated capacitance of a capacitor
C
r
capacitance value for which the capacitor has been designed
3.23
rated chopped lightning impulse withstand voltage
required peak value of the chopped lightning impulse withstand voltage which characterises
the insulation of a grading capacitor as regards the withstand tests
Note 1 to entry: The definitions and the standard parameters applicable to chopped impulses are specified in
IEC 60060-1.
62146-1 © IEC:2013 – 11 –
3.24
rated frequency of a capacitor
f
r
frequency for which the capacitor has been designed
[SOURCE: IEC 60050-436:1990, 436-01-14, modified by addition of symbol]
3.25
rated insulation level
test voltages, under specified conditions, that the insulation is designed to withstand
Note 1 to entry: These test voltages can be for instance:
a) rated chopped and lightning impulse and short duration power frequency withstand voltages for capacitors
installed on circuit-breaker with rated voltage lower than 300 kV.
b) rated switching, lightning, chopped impulse and short duration power frequency withstand voltages for
capacitors installed on circuit-breaker with rated voltage equal to or greater than 300 kV.
Note 2 to entry: The rated insulation levels of the grading capacitor should be equal to or higher than the relevant
requirements for the circuit-breaker interrupting unit.
[SOURCE: IEC 60050-421:1990, 421-09-02, modified Note to entry]
3.26
rated lightning impulse withstand voltage
required peak value of the lightning impulse withstand voltage which characterises the
insulation of an equipment as regards the withstand tests
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
specified in IEC 60060-1.
3.27
rated short duration power frequency withstand voltage
required r.m.s. value of sinusoidal power frequency voltage that the equipment withstands
during tests made under specified conditions and for a duration of 1 min unless otherwise
specified
3.28
rated switching impulse withstand voltage
required peak value of the switching impulse withstand voltage which characterises the
insulation of an equipment as regards the withstand tests
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
as specified in IEC 60060-1.
3.29
rated temperature category of a capacitor
range of temperature of the ambient air or other medium in which the capacitor is immersed
during the service life and for which it has been designed
3.30
rated voltage of a capacitor
U
cr
r.m.s. value of the alternating voltage assigned to the capacitor for identification and at which
the capacitor is designed to operate continuously
3.31
rated voltage of circuit-breaker
U
r
indicates the upper limit of the highest voltage of systems for which the circuit-breaker is
intended
– 12 – 62146-1 © IEC:2013
Note 1 to entry: See IEC 62271-1.
Note 2 to entry: U used in IEC 62271 series corresponds to U presented in IEC 60071.
r m
3.32
resonance frequency
frequency for which the reactance of the intrinsic capacitance of the capacitor is equal to the
reactance of the self-inductance of the capacitor
3.33
sample
device for testing
Note 1 to entry: Examples of such devices are a complete small capacitor, or the housing of a grading capacitor
with metal end flanges filled with impregnating fluid.
3.34
tangent of the loss angle of a capacitor
tan δ
ratio between the equivalent series resistance and the capacitive reactance of a capacitor at
specified sinusoidal alternating voltage and frequency
[SOURCE: IEC 60050-436:1990, 436-04-11]
3.35
voltage grading factor of a circuit-breaker
(F )
VG
value that defines the standard values of rated voltages for the grading capacitor.
Note 1 to entry: This factor is the ratio between the actual maximum power frequency voltage fraction across one
interrupter unit of a multi-break circuit-breaker and the calculated linear power frequency voltage distribution per
interrupting unit.
Note 2 to entry: It is dependent on the circuit-breaker design, of the capacitance value of the grading capacitor and
its tolerance and of the safety margin.
4 Abbreviations
TRV Transient Recovery Voltage
C Rated capacitance of a capacitor
r
f Rated frequency of a capacitor
r
U
Rated voltage of a capacitor
cr
U Rated voltage of circuit-breaker
r
tan δ Tangent of the loss angle of a capacitor
F
Voltage grading factor of a circuit-breaker
VG
U Short-duration power frequency withstand voltage for the grading capacitor
CPF
U Short-duration power frequency withstand voltage across the open circuit-breaker
PF
U Rated lightning impulse withstand voltage for the grading capacitor
CLIWL
U Combined lightning and frequency withstand voltage for the circuit-breaker
(LIWL + PF)
U Rated switching impulse withstand voltage for the grading capacitor
CSIWL
U Combined switching and frequency withstand voltage for the circuit-breaker
(SIWL + PF)
U
Chopped lightning impulse voltage for the grading capacitor
CCHOPPED
BIL Bushings insulated level
SIL Standard insulation level
RIV
Radio interference voltage
62146-1 © IEC:2013 – 13 –
5 Normal and special service conditions
5.1 General
The grading capacitors are intended to be installed on circuit-breakers, for which the normal
and special service conditions are described in IEC 62271-1.
Additional service conditions specific to the capacitors are given in 5.2.3.
5.2 Normal service conditions
5.2.1 Ambient temperature
For outdoor application the normal service conditions of the grading capacitor are given in
IEC 62271-1.
For an immersed capacitor, the temperature around the capacitor can be higher than the
ambient air around the breaker. The preferred values of maximum surrounding temperature to
be specified should be: 60 °C, 70 °C, 80 °C.
The internal operating temperature of the capacitor is higher than the maximum temperature
around the capacitor and should be considered by the capacitor manufacturer.
5.2.2 Mechanical stress and vibrations
Mechanical stress and vibrations due to:
– forces due to wind and ice are according to IEC 62271-1;
– forces on the terminals due to the circuit-breaker connection which value shall be defined
by agreement between purchaser and capacitor manufacturer;
– forces due to the operations consequent to vibrations, such as opening and closing, of the
circuit-breaker.
Vibrations due to earthquakes are not considered for normal service conditions.
5.2.3 Additional service conditions for indoor and completely immersed grading
capacitor
The completely immersed grading capacitors are subjected to the following other conditions:
pressure;
– the influence of SF
– the resistance of the capacitor materials against the decomposition products of SF .
5.3 Special service conditions
5.3.1 General
The special service conditions are given in IEC 62271-1; if they are required, the purchaser
will specify it to the capacitor manufacturer.
5.3.2 Earthquakes
For the earthquake stress the grading capacitors have to be considered as accessories of the
circuit-breaker and in this way they have to satisfy the seismic qualification rules according to
IEC 62271-300.
NOTE Assuming that the mechanical stresses on circuit-breakers due to seismic activity are covered by the
relevant standards, the stressing of the grading capacitor is low in comparison to transport or operation stressing.
– 14 – 62146-1 © IEC:2013
6 Ratings
6.1 Rated voltage (U )
cr
The rated voltage U of a grading capacitor is based on the following equation:
cr
U × F
r VG
U =
cr
n× 3
where
U is the rated voltage of the circuit-breaker;
r
n is the number of interrupter units per pole;
F is the voltage grading factor, standardized to 1,2.
VG
NOTE 1 This value is 20 % higher than the linear voltage distribution and covers most of the common
applications.
NOTE 2 In case of single break circuit-breaker the grading factor is not applicable, In some cases, a higher
voltage grading factor may be necessary (for example due to low capacitance of grading capacitor and/or high
stray capacitance of the circuit-breaker and/or more than 2 interrupter units).
6.2 Rated insulation level
The insulation level and the test voltage value shall be obtained by the criteria defined in the
type and routine test clauses.
Guidance for the choice of the insulation level is given:
– in IEC 62271-1 for the grading capacitor of an air insulated circuit-breaker;
– in IEC 62271-1 for the grading capacitor of an immersed capacitor in a dead tank breaker;
– in IEC 62271-203 for the grading capacitor of an immersed capacitor in a gas insulated
switchgear.
The grading factor F has to be calculated for the circuit-breaker depending on its design.
GV
The voltage stress for the capacitor shall be calculated with the following equation using the
test voltage across the complete open circuit-breaker (see IEC 62271-1):
U × F
PF VG
U =
CPF
n
U × F
(LIWL + PF) VG
U =
CLIWL
n
U × F
(SIWL + PF) VG
U =
CSIWL
n
U = 1,15×U
CCHOPPED CLIWL
where
U is the short-duration power frequency withstand voltage for the grading
CPF
capacitor;
U is the short-duration power frequency withstand voltage across the open
PF
circuit-breaker;
62146-1 © IEC:2013 – 15 –
U is the rated lightning impulse withstand voltage for the grading capacitor;
CLIWL
U is the combined lightning and frequency withstand voltage for the circuit-
(LIWL + PF)
breaker;
U is the rated switching impulse withstand voltage for the grading capacitor;
CSIWL
U is the combined switching and frequency withstand voltage for the circuit-
(SIWL + PF)
breaker
U is the chopped lightn
...
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