IEC 62146-2:2023

IEC 62146-2 ®
Edition 1.0 2023-01
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Capacitors for high‑voltage alternating current circuit‑breakers –
Part 2: TRV capacitors
Condensateurs pour disjoncteurs à courant alternatif haute tension –
Partie 2: Condensateurs TTR
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IEC 62146-2 ®
Edition 1.0 2023-01
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Capacitors for high‑voltage alternating current circuit‑breakers –

Part 2: TRV capacitors
Condensateurs pour disjoncteurs à courant alternatif haute tension –

Partie 2: Condensateurs TTR
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 31.060; 31.060.70 ISBN 978-2-8322-6353-2

– 2 – IEC 62146-2:2023 © IEC 2023
CONTENTS
FOREWORD . 4
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 7
4 Abbreviated terms . 8
5 Service conditions . 8
6 Ratings . 9
6.1 Rated voltage (U ) . 9
cr
6.2 Rated insulation level . 9
6.3 Rated frequency (f ) . 11
r
7 Design and construction . 11
7.1 Capacitance tolerances . 11
7.2 Capacitor loss requirements . 11
7.3 Partial discharge level . 11
7.4 Angle of mounting . 11
7.5 Minimum withstand value of mechanical bending load . 11
7.5.1 Capacitors mounted on air insulated circuit-breaker . 11
7.5.2 Immersed capacitors . 12
7.5.3 Freestanding capacitors . 12
7.6 Requirements for impregnation medium in capacitor . 12
7.7 Protection against corrosion . 12
7.8 Marking of the equipment . 12
7.9 Creepage distances for outdoor insulators . 13
7.10 Tightness . 13
8 Type tests . 13
8.1 Information for identification of specimens . 13
8.2 Information to be included in type-test reports . 13
8.3 Test conditions . 13
8.4 Electrical type tests . 13
8.4.1 General . 13
8.4.2 Switching impulse voltage test . 14
8.4.3 Lightning and chopped impulse voltage test . 14
8.5 Voltage test at low and high temperature . 15
8.5.1 Test procedure . 15
8.5.2 Capacitor reduced-scale model design . 15
8.6 Radio Interference Voltage (RIV) test . 15
8.7 Short-circuit discharge test . 16
8.8 Resonance frequency measurements. 16
8.9 Mechanical bending test . 16
8.10 Tightness test at different temperatures . 16
8.11 Tightness test to check gas ingress from pressurized environment . 16
8.12 Vibration test . 16
9 Routine tests . 17
9.1 General . 17
9.2 Test conditions . 17
9.3 Capacitance and loss angle measurements at power frequency . 17

9.4 Power frequency voltage test . 17
9.5 Partial discharge test . 18
9.6 Tightness test . 18
9.6.1 General . 18
9.6.2 Oil impregnated capacitor . 18
9.6.3 Tightness test for gas filled capacitors . 18
9.7 Visual inspection and dimensional check . 18
10 Recommendations for transport, storage, erection, operation, and maintenance . 19
11 Safety . 19
11.1 General . 19
11.2 Precautions by manufacturers . 19
11.3 Precautions by users . 19
11.4 National regulations . 19
12 Environmental aspects . 20

Figure 1 – Electrical type tests sequence . 14
Figure 2 – Reduced scale model capacitor element geometry . 15
Figure 3 – Electrical routine test sequence . 17

Table 1 – Standard insulation levels – Range I (U < 300 kV). 9
r
Table 2 – Standard insulation levels – Range II (U ≥ 300 kV) . 10
r
Table 3 – Partial discharge test voltages and permissible levels . 11

– 4 – IEC 62146-2:2023 © IEC 2023
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
CAPACITORS FOR HIGH‑VOLTAGE ALTERNATING
CURRENT CIRCUIT‑BREAKERS –
Part 2: TRV capacitors
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,
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preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with
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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
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3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
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services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
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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.
IEC 62146-2 has been prepared by IEC technical committee 33: Power capacitors and their
applications. It is an International Standard.
The text of this International Standard is based on the following documents:
Draft Report on voting
33/685/FDIS 33/686/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.

This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.
This International Standard is to be used in conjunction with IEC 62146-1:2013 and
IEC 62146-1:2013/AMD1:2016.
A list of all parts in the IEC 62146 series, published under the general title Capacitors for
high-voltage alternating current circuit-breakers, can be found on the IEC website. The title of
the series was changed in 2022 by decision of TC 33, and the title of IEC 62146-1 will be
modified accordingly in its next edition.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
– 6 – IEC 62146-2:2023 © IEC 2023
CAPACITORS FOR HIGH‑VOLTAGE ALTERNATING
CURRENT CIRCUIT‑BREAKERS –
Part 2: TRV capacitors
1 Scope
This part of IEC 62146 is applicable to TRV capacitors used on high-voltage alternating current
circuit-breakers with rated voltages above 100 kV with 50 Hz or 60 Hz.
TRV capacitors are installed phase to earth, either in parallel to the bushing on dead tank
circuit-breakers, or immersed inside the circuit-breaker, or freestanding close to the circuit-
breaker. Their function is to limit the transient recovery voltage (TRV) and the rate of rise of
recovery voltage (RRRV) on the circuit-breaker. Capacitors in compliance with this document
can be used as TRV capacitor.
This document applies to TRV capacitors falling into one or both of the following categories for:
– mounting on or close to air insulated switchgear (AIS) dead tank and live tank circuit-
breakers, or
– mounting on gas insulated switchgear (GIS) circuit-breakers.
The testing for each of the above applications is in some cases different.
This document does not apply to grading capacitors installed in parallel to the chambers of the
circuit-breaker, which are specified in IEC 62146-1.
This document does not apply to capacitors not directly associated with high-voltage alternating
current circuit-breakers.
The object of this document is:
– to define uniform rules regarding performances, testing and rating
– to define specific safety rules
– to provide a guidance for installation and operation
The TRV capacitor is a sub-component for the circuit-breaker and is specified in accordance
with the circuit-breaker specifications according to IEC 62271-1, IEC 62271-100, and if
applicable to IEC 62271-203.
TRV capacitors are commonly built with composite or ceramic housings (insulators). Those
insulators follow IEC 61462 or IEC 62155. Other housings can be used if they can sustain
applicable type tests according to IEC 61462 and IEC 62155.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies.
For undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 60060-1:2010, High-voltage test techniques – Part 1: General definitions and test
requirements
IEC 60358-1:2012, Coupling capacitors and capacitor dividers – Part 1: General rules
IEC 60815 (all parts), Selection and dimensioning of high-voltage insulators intended for use in
polluted conditions
IEC 60871-1:2014, Shunt capacitors for a.c. power systems having a rated voltage above
1 000 V – Part 1: General
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 62146-1:2013, Grading capacitors for high-voltage alternating current circuit-breakers –
Part 1: General
IEC 62146-1:2013/AMD1:2016
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 62271-1:2017, High-voltage switchgear and controlgear – Part 1: Common specifications
for alternating current switchgear and controlgear
IEC 62271-1:2017/AMD1:2021
IEC 62271-100:2021, High-voltage switchgear and controlgear – Part 100: Alternating-current
circuit-breakers
IEC 62271-203, High-voltage switchgear and controlgear – Part 203: AC gas-insulated metal-
enclosed switchgear for rated voltages above 52 kV
IEC GUIDE 109, Environmental aspects – Inclusion in electrotechnical product standards
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 62146-1:2013 and
the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1
capacitor
two-terminal device characterized essentially by its capacitance
[SOURCE: IEC 60050-151:2001, 151-13-28]
3.2
TRV capacitor
capacitor for installation on high-voltage circuit-breakers phase to earth, either on circuit-
breaker bushings or freestanding close to the circuit-breaker to limit TRV or RRRV
Note 1 to entry: The TRV capacitors alone are accessories of the circuit-breaker.

– 8 – IEC 62146-2:2023 © IEC 2023
3.3
freestanding capacitor
TRV capacitor installed as an accessory to the circuit-breaker and mounted in its proximity
Note 1 to entry: The freestading capacitor does not need to be fixed at the same supporting structure of the circuit-
breaker.
Note 2 to entry: Freestanding capacitors are sometimes named standalone TRV capacitors.
3.4
ambient temperature
temperature of the insulating fluid surrounding the capacitor at its surface
3.5
transient recovery voltage
TRV
recovery voltage during the time in which it has a significant transient character
Note 1 to entry: The transient recovery voltage may be oscillatory or non-oscillatory or a combination of these
depending on the characteristics of the circuit and the switching device. It includes the voltage shift of the neutral of
a polyphase circuit.
Note 2 to entry: The transient recovery voltages in three-phase circuits are, unless otherwise stated, that across
the first pole to clear, because this voltage is generally higher than that which appears across each of the other two
poles.
[SOURCE: IEC 60050-441:1984, 441-17-26]
3.6
rate of rise of recovery voltage
RRRV
first peak transient recovery voltage divided by the total time from zero voltage to peak voltage
Note 1 to entry: Levels of TRV and the RRRV are key factors in determining whether the fault can be cleared
successfully.
3.7
voltage factor
F
V
factor used when the TRV capacitor is composed of several capacitors connected in series
phase to earth
Note 1 to entry: F will affect the insulating voltage levels of the individual capacitors to add some safety margin.
v
4 Abbreviated terms
Clause 4 of IEC 62146-1:2013 is applicable with the following additions.
F voltage factor
v
TRV transient recovery voltage
RRRV rate of rise of recovery voltage
5 Service conditions
For TRV capacitors installed on the circuit-breaker or immersed capacitors, the service
conditions are given in IEC 62146-1:2013, Clause 5.
For freestanding capacitors, the service conditions are given in IEC 60358-1:2012, Clause 4.

6 Ratings
6.1 Rated voltage (U )
cr
The rated voltage U of a TRV capacitor connected between one phase of a three-phase
cr
system and earth shall be equal or greater than the value of the rated voltage U of the circuit-
r
breaker divided by √3.
Preferred values for U are given in IEC 62271-1.
r
NOTE U used in IEC 62271 series and in this standard corresponds to U presented in IEC 60071-1.
r m
6.2 Rated insulation level
The choice of the insulation level for equipment shall be made in accordance with the standard
insulation levels, based on its highest voltage for equipment U . Guidance for the choice of the
r
insulation level is given below.
In case of TRV capacitor of an air insulated circuit-breaker installed parallel to the bushing, the
insulation levels are according to IEC 62271-1.
In case of TRV capacitor installed in a gas insulated switchgear (GIS and dead tank breaker),
the insulation levels are according to IEC 62271-203.
In case of TRV capacitor installed freestanding, the insulation levels are according to Table 1
and Table 2 (adapted from IEC 60358-1). The rated insulation levels shall be based on the rated
voltage of the circuit-breaker U .
r
Table 1 – Standard insulation levels – Range I (U < 300 kV)
r
Rated voltage of Rated power- Rated lightning Rated switching
the circuit- frequency withstand impulse withstands withstand voltage
breaker (U ) voltage voltage
r
Range
(RMS) (RMS) (peak) (peak)
kV kV kV kV
100 185 450
185 450
230 550
230 550
I 275 650
275 650
325 750
395 950
460 1 050
NOTE 1 For exposed installations it is recommended to choose the highest insulation level.
NOTE 2 For alternative levels, see IEC 60071-1.

– 10 – IEC 62146-2:2023 © IEC 2023
Table 2 – Standard insulation levels – Range II (U ≥ 300 kV)
r
Rated voltage of Rated power- Rated lightning Rated switching
the circuit- frequency withstand impulse withstands withstand voltage
breaker (U ) voltage voltage
r
Range
(RMS) (RMS) (peak) (peak)
kV kV kV kV
395 750
460 850
1 050
460 850
1 050
1 050
510 950
1 175
1 050
1 175
1 175
420 950
1 300
1 300
630 1 050
1 425
1 175
1 300
1 300
550 1 050
1 425
1 425
680 1 175
1 550
II
1 675
1 300
1 800
1 800
800 1 425
1 950
1 950
975 1 550
2 100
1 950
1 425
2 100
2 100
1 550
2 250
1 100
2 250
1 675
2 400
2 400
1 800
2 550
2 100
1 675
2 250
2 250
1 800
1 200
2 400
2 550
1 950
2 700
NOTE 1 For exposed installations it is recommended to choose the highest insulation level.
NOTE 2 For alternative levels, see IEC 60071-1.

6.3 Rated frequency (f )
r
The standard considered values for the rated frequency are 50 Hz or 60 Hz.
7 Design and construction
7.1 Capacitance tolerances
The measured capacitance shall not differ from the rated capacitance (C ) by more than ±5 %
r
for all type of TRV capacitors unless otherwise agreed between manufacturer and user.
7.2 Capacitor loss requirements
Subclause 7.2 of IEC 62146-1:2013 is applicable.
7.3 Partial discharge level
The partial discharge level shall not exceed the limits specified in Table 3 at the partial
discharge test voltage specified in the same table according to the procedures of clause 9.5.
Table 3 – Partial discharge test voltages and permissible levels
Permissible PD level (pC) Permissible PD level (pC)
PD test voltage (RMS)
Air insulated capacitors Immersed capacitors
1,2 𝑈𝑈 ≤ 10 ≤ 5
r
1,2 𝑈𝑈
r
≤ 5 ≤ 3
√
NOTE 1 The permissible PD level is also valid for frequencies different from the system frequency.
NOTE 2 For big TRV capacitance values (e.g. higher than 10 nF), testing laboratory background noise can affect
the PD measurement, in that case an agreement between purchaser and manufacturer should be made.
NOTE 3 For TRV capacitors composed of several units (N) connected in series, if only the capacitor units are
tested, the value of the PD test voltage for each unit will be equal to:
1,05 × PD test voltage of the TRV capacitor / N

7.4 Angle of mounting
For non-immersed applications, the capacitors shall be designed to be installed in vertical or
oblique directions up to 45°.
For immersed applications, the capacitors shall be designed to be installed in any direction:
vertical, horizontal, or oblique.
7.5 Minimum withstand value of mechanical bending load
7.5.1 Capacitors mounted on air insulated circuit-breaker
These capacitors are fixed on both extremities of the circuit-breaker bushings. The bushings
support the mechanical stress due to the connections.
For these capacitors the test bending moment M shall be calculated as follows:
C
– 12 – IEC 62146-2:2023 © IEC 2023
m 1

M 50+ ××gl×
(1)
C

2 0,7

where:
M is in Nm;
C
l is the length of the capacitor in m;
m is the weight of the capacitor in kg;
g is the gravitational acceleration = 9,81 m/s .
Notwithstanding the above calculation, the minimum value for M shall be 2000 Nm.
C
NOTE 1 The factor of 0,7 has been taken from IEC 62155:2003, 8.3.1.
NOTE 2 The supplementary weight of 50 kg has been reduced in comparison with grading capacitors which can be
installed horizontally.
7.5.2 Immersed capacitors
The test bending moment M shall be calculated in accordance with the IEC 62146-1:2013,
C
7.4.2.
7.5.3 Freestanding capacitors
The test bending moment M shall be in accordance with the minimum bending load given in
C
IEC 60358-1:2012, 6.4.
7.6 Requirements for impregnation medium in capacitor
The capacitor manufacturer shall specify the type of the impregnation medium (liquid, gas or
dry) used in the capacitor.
7.7 Protection against corrosion
The protection against corrosion shall be in accordance with IEC 62146-1:2013, 7.6.
7.8 Marking of the equipment
The capacitor shall be provided with nameplates which contain at least the following
information:
– name or mark of the capacitor manufacturer,
– year of manufacture,
– capacitor manufacturer's type designation,
– serial number or equivalent,
– rated voltage of capacitor (U ),
cr
– rated frequency of capacitor (f ),
r
– rated capacitance (C ) and its tolerances,
r
– power frequency test voltage U ,
CPF
– acceptable range of ambient temperature (as declared by the manufacturer),
– quantity of oil or rated gas filling pressure,
=
– oil, gas or dry designation,
– reference to the relevant edition of IEC 62146-2.
7.9 Creepage distances for outdoor insulators
For outdoor insulation susceptible to contamination, the minimum rated specific creepage
distance measured on the insulation surface in millimetres is given in the IEC 60815 series.
NOTE Creepage distances of TRV capacitors usually have the same specifications as the breaker bushing.
7.10 Tightness
The tightness shall be in accordance with IEC 62146-1:2013, 7.9.
8 Type tests
8.1 Information for identification of specimens
The identification of specimens shall be in accordance with IEC 62146-1:2013, 8.1.
8.2 Information to be included in type-test reports
The information to be included in type test reports shall be in accordance with
IEC 62146-1:2013, 8.2.
8.3 Test conditions
The test conditions shall be in accordance with IEC 62146-1:2013, 8.3.
8.4 Electrical type tests
8.4.1 General
The objective of the electrical type tests is to test the electrical withstand of the internal and
external parts of the capacitor.
For a TRV capacitor installed parallel to the circuit-breaker bushing, if the wet tests and RIV
tests are performed with the TRV capacitor mounted on the circuit-breaker as part of the circuit-
breaker type tests, the dry tests will replace the wet tests on the TRV capacitor using the same
level of voltage.
For a stand-alone TRV capacitor, as it is considered as an equipment itself, wet tests and RIV
tests shall be performed.
A dielectric type test may also be considered valid if it is made on a capacitor which is higher
electrically stressed per element subject to agreement between manufacturer and purchaser.
Impulse and RIV tests shall be performed on the same TRV capacitor unit. The test sequence
is described in Figure 1.
NOTE 1 For immersed TRV capacitors, the dry tests will replace the wet tests on the TRV capacitor using the same
level of voltage.
NOTE 2 By an agreement between the manufacturer and the purchaser the order of the test sequence (Figure 1)
can be modified.
– 14 – IEC 62146-2:2023 © IEC 2023

Figure 1 – Electrical type tests sequence
8.4.2 Switching impulse voltage test
The switching impulse voltage test procedure shall be in accordance with IEC 62146-1:2013,
8.4.5. The test voltage level shall be in accordance with 6.2. For capacitors installed in stand-
alone, this test shall be performed in wet conditions; the wet test procedure shall be in
accordance with IEC 60060-1.
8.4.3 Lightning and chopped impulse voltage test
The lightning and chopped impulse voltage test procedure shall be in accordance with
IEC 62146-1:2013, 8.4.6. The test voltage level shall be in accordance with 6.2.
The sequence and number of impulses shall be subjected successively to:
– 15 lightning impulses of positive polarity; followed by
– 15 chopped lightning impulses of positive polarity; and by
– 1 lightning impulse of negative polarity; followed by
– 15 chopped lightning impulses of negative polarity; and by
– 14 lightning impulse of negative polarity.
The waveform of the applied impulses shall be in accordance with IEC 60060-1, but the front
time may be increased to a maximum of 8 μs for large capacitance values, owing to the
limitations of the testing equipment, as in IEC 60358-1:2012, 10.1.3.
NOTE The number of lightning and lightning chopped impulses for TRV capacitors is different compared to
IEC 62146-1. TRV capacitors are connected phase to earth and for that reason they need to sustain a larger number
of impulses than grading capacitors.

8.5 Voltage test at low and high temperature
8.5.1 Test procedure
The test can be carried out on a capacitor reduced-scale model according to 8.5.2.
An equivalence table shall be prepared by the manufacturer to compare the tests performed in
the capacitor reduced-scale model with the TRV capacitor.
An AC voltage of 1,9 U shall be applied for 8 h between the terminals of the capacitors
cr
maintained at a temperature equal to the minimum value specified for the capacitor.
An AC voltage of 1,9 U shall be applied for 8 h between the terminals in an atmosphere lightly
cr
ventilated and with a temperature of air approximately equal to the maximum value specified
for the capacitor.
For both, minimum and maximum temperature tests, the capacitor under test needs to have the
test temperature stabilized before to start the test.
The capacitor reduced-scale model passes the tests if: (1) it passes the routine tests at ambient
temperature (Clause 9) and (2) if the capacitance measured before and after the tests, does
not increase more than an amount corresponding to the breakdown of a capacitor element.
NOTE The 1,9 factor and the 8 h are the most severe test conditions adapted from IEC 60358-1:2012, 5.3.1.
Depending on the system earthing conditions where the TRV capacitor will be installed, reduced rated factors and
test duration are permissible by agreement between manufacturer and user .
8.5.2 Capacitor reduced-scale model design
The capacitor reduced scale model is manufactured by using the same production material, and
processing procedures as the TRV capacitor.
The capacitor reduced-scale model shall have at least 5 series connected capacitor elements
or by agreement between manufacturer and user.
In particular, the reduced scale model capacitor element shall have:
– Same border distances "z" (Figure 2) between electrodes and dielectrics
– Same basic type of dielectric materials
– Same thickness of dielectric layer
– Same impregnated dielectric fluid or gas or insulation

Figure 2 – Reduced scale model capacitor element geometry
8.6 Radio Interference Voltage (RIV) test
For TRV capacitors installed on the circuit-breaker, RIV test is not required to be performed
separately on the TRV capacitor unit alone since they are affected by and performed part of the
required circuit-breaker type test.

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For capacitors installed freestanding, this test shall be in accordance with
IEC 60358-1:2012, 10.3.
8.7 Short-circuit discharge test
This test is adapted from the IEC 60871-1. The test can be carried out on a capacitor reduced-
scale model according to 8.5.2. The unit shall be charged by means of DC voltage and then
discharged through a gap situated as close as possible to the capacitor. It shall be subjected
to five such discharges within 10 min.
as the TRV capacitor.
The test voltage shall be adapted to be equivalent to 2,5 U
cr
The capacitance shall be measured before and after the discharge tests. The differences
between the two measurements shall be less than an amount corresponding to either
breakdown of an element.
NOTE 1 The purpose of the discharge test is to reveal any weak design of the internal connections.
NOTE 2 For applications where overvoltages and/or transient currents are limited, test voltages lower than 2,5 U
cr
can be used, as agreed between the manufacturer and the purchaser.
8.8 Resonance frequency measurements
The resonance frequency measurement test procedure shall be in accordance with
IEC 62146-1:2013, 8.7.
8.9 Mechanical bending test
The value of the test force F is calculated from the bending moment M defined in 7.5.
c c
For TRV capacitors installed on the circuit-breaker and immersed capacitor, the mechanical
bending test procedure shall be in accordance with IEC 62146-1:2013, 8.8.
For TRV capacitors installed freestanding, the test procedure shall be in accordance with
IEC 60358-1:2012, 11.
8.10 Tightness test at different temperatures
The tightness tests at different temperature procedures shall be in accordance with
IEC 62146-1:2013, 8.9.
8.11 Tightness test to check gas ingress from pressurized environment
For TRV immersed capacitors, the tightness test procedure to check gas ingress from
pressurized environment shall be in accordance with IEC 62146-1:2013, 8.10.
8.12 Vibration test
For TRV capacitors installed on the circuit-breaker and immersed capacitors, the vibration test
procedure shall be in accordance with IEC 62146-1:2013, 8.11.
For TRV capacitors installed freestanding, this test shall not be performed.

9 Routine tests
9.1 General
General recommendations to perform routine tests shall be in accordance with
IEC 62146-1:2013, 9.1. The electrical routine test sequence is presented in Figure 3.

Figure 3 – Electrical routine test sequence
9.2 Test conditions
Test conditions to perform routine tests shall be according to 8.3.
9.3 Capacitance and loss angle measurements at power frequency
The capacitance measurement at power frequency and tangent of the loss angle (tan δ) shall
be in accordance with IEC 62146-1:2013, 8.4.2 and 8.4.3.
In order to reveal any change in capacitance due to the puncture of one or more elements
during the first voltage application, a preliminary capacitance measurement shall be made
before the voltage routine tests, at a sufficiently low voltage (equal or less than 30 % of rated
voltage; suggested value is 10 kV in order to obtain a reference value for future site
measurement) to ensure that no puncture of an element has occurred.
9.4 Power frequency voltage test
The power frequency voltage test procedure shall be in accordance with IEC 62146-1:2013,
8.4.7. The test voltage level shall be in accordance with 6.2. For capacitors installed
freestanding, during type test validation, this test shall be performed in wet conditions (wet test
procedure shall be in accordance with IEC 60060-1).

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9.5 Partial discharge test
Acceptance criteria shall be in accordance with 7.3. The partial discharges shall be performed
for the two levels of voltage and the acceptance criteria specified.
After a pre-stressing performed according to procedure A or B, the partial discharge test voltage
specified in Table 3 is applied and the corresponding partial discharge level shall be measured
within 30 s. The limits of partial discharge level are specified in 7.3.
Procedure A: The partial discharge test voltages are reached while decreasing the voltage after
the power frequency withstand test.
Procedure B: The partial discharge test is performed after the AC voltage withstand test. The
applied voltage is raised to 80 % of the withstand voltage, maintained for not less than 60 s,
then reduced without interruption to the specified partial discharge test voltage.
If not otherwise specified, the choice of procedure is left to the manufacturer (recommended
method is procedure A). The test method used shall be indicated in the test report.
9.6 Tightness test
9.6.1 General
According to the insulating dielectric fluid and the application, different test methods shall be
applied.
The tightness test is not required for capacitors with solid internal insulation (e.g. ceramic
capacitors) that are not sealed from the insulating fluid.
9.6.2 Oil impregnated capacitor
9.6.2.1 Air insulated capacitors
The tightness test for air insulated TRV capacitors shall be in accordance with
IEC 62146-1:2013, 9.6.2.1.
9.6.2.2 Immersed capacitors
The tightness test for immersed TRV capacitors shall be in accordance with IEC 62146-1:2013,
9.6.2.2.
9.6.3 Tightness test for gas filled capacitors
9.6.3.1 Air insulated capacitors
The tightness test for gas filled capacitors to be installed in air shall be in accordance with
IEC 62146-1:2013, 9.6.3.1.
9.6.3.2 Immersed capacitors
The tightness test for gas filled capacitors to be installed immersed in the circuit-breaker shall
be performed according to 9.6.3.1.
9.7 Visual inspection and dimensional check
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