IEC 60358-3:2013

Coupling capacitors and capacitor dividers - Part 3: AC or DC coupling capacitor for harmonic-filters applications

IEC 60358-3:2013 applies to AC or DC single-phase coupling capacitor, with rated voltage higher than 1 000 V, connected line to ground with the low voltage terminal either permanently earthed or connected to a tuning device for harmonic-filters applications. It replaces Clause 1 of IEC 60358-1:2012. Keywords: AC or DC single-phase coupling capacitor
This publication is to be read in conjunction with IEC 60358-1:2012.

Condensateurs de couplage et diviseurs capacitifs - Partie 3: Condensateur de couplage à courant alternatif ou à courant continu pour des applications à filtres harmoniques

L'IEC 60358-3:2013 s'applique aux condensateurs de couplage monophasés à courant alternatif ou à courant continu, de tension assignée supérieure à 1 000 V, connectés entre la ligne et la terre, avec la borne basse tension connectée de manière permanente à la terre ou connectée à un dispositif d'accord pour des applications à filtres harmoniques. Il remplace l'Article 1 de la CEI 60358-1:2012. Mots clés: condensateurs de couplage monophasés à courant alternatif ou à courant continu
Cette publication doit être lue conjointement avec la CEI 60358-1:2012.

General Information

• Status: Published
• Publication Date: 26-Nov-2013
• ICS: 29.120.99 - Other electrical accessories
• ICS: 29.240.99 - Other equipment related to power transmission and distribution networks
• ICS: 35.100.10 - Physical layer
• Technical Committee: TC 33 - Power capacitors and their applications
• Drafting Committee: MT 20 - TC 33/MT 20
• Current Stage: PPUB - Publication issued
• Start Date: 27-Nov-2013
• Completion Date: 15-Feb-2014

Standards Content (Sample)

IEC 60358-3 ®
Edition 1.0 2013-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Coupling capacitors and capacitor dividers –
Part 3: AC or DC coupling capacitor for harmonic-filters applications

Condensateurs de couplage et diviseurs capacitifs –
Partie 3: Condensateur de couplage à courant alternatif ou à courant continu
pour des applications à filtres harmoniques
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IEC 60358-3 ®
Edition 1.0 2013-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Coupling capacitors and capacitor dividers –

Part 3: AC or DC coupling capacitor for harmonic-filters applications

Condensateurs de couplage et diviseurs capacitifs –

Partie 3: Condensateur de couplage à courant alternatif ou à courant continu

pour des applications à filtres harmoniques

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX N
ICS 29.120.99; 29.240.99 ISBN 978-2-8322-1274-5

– 2 – 60358-3 © IEC:2013
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions. 6
4 Service conditions . 7
5 Ratings . 7
6 Design requirements . 7
7 Test conditions . 7
8 Classification of tests . 7
9 Routine tests . 8
10 Type tests . 10
11 Special tests – Mechanical strength test . 11
12 Marking of the equipment . 11
Annex AA Typical diagram of a filter capacitor . 12
Annex BB (informative) High-frequency characteristics of filter capacitors . 13
Bibliography . 15

Figure 300 – Connection for voltage test of tuning device . 9
Figure AA.1 – Example of a diagram for a filter capacitor (with and without low voltage
terminal) . 12
Figure AA.2 – Example of a diagram for a filter capacitor with tuning device . 12
Figure BB.1 – Wiring diagram of the measuring circuit for the high frequency
capacitance and equivalent series resistance of a coupling capacitor . 14
Figure BB.2 – Relation between length and capacitance where capacitive deviation –
20/+50 % can be fulfilled up to 500 kHz . 14

Table 300 – Marking of the rating plate . 11

60358-3 © IEC:2013 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
COUPLING CAPACITORS AND CAPACITOR DIVIDERS –

Part 3: AC or DC coupling capacitor
for harmonic-filters applications

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
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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 60358-3 has been prepared by IEC technical committee 33: Power
capacitors and their applications.
The text of this standard is based on the following documents:
CDV Report on voting
33/510/CDV 33/526/RVC
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.

– 4 – 60358-3 © IEC:2013
A list of all parts in the IEC 60358 series, published under the general title Coupling
capacitors and capacitor dividers, can be found on the IEC website.
This standard is Part 3 of IEC 60358, published under the general title Coupling capacitor
and capacitor dividers.
This International Standard is to be used in conjunction with the latest edition of
IEC 60358-1:2012 and its amendments. It was established on the basis of the first edition
(2012) of that standard.
This Part 3 supplements or modifies the corresponding clauses in IEC 60358-1:2012.
When a particular subclause of Part 1 is not mentioned in this Part 3, that subclause applies
as far as is reasonable. When this standard states “addition”, “modification” or “replacement”,
the relevant text in Part 1 is to be adapted accordingly.
For additional clauses, subclauses, figures, tables or annexes, the following numbering
system is used:
 subclauses, tables and figures which are additional to those in Part 1 are numbered
starting from 300;
 additional tables or annexes are lettered AA, BB, etc.
 as the notes are integrated into the clauses, their numbering starts from 1 as usual.
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.
IMPORTANT – The “colour inside” logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct
understanding of its contents. Users should therefore print this publication using a
colour printer.
60358-3 © IEC:2013 – 5 –
INTRODUCTION
This series consists of the following parts:
IEC 60358-1:2012, Coupling capacitor and capacitor dividers – Part 1: General rules
IEC 60358-2:2013, Coupling capacitor and capacitor dividers – Part 2: AC or DC single-phase
coupling capacitor connected between line and ground for power line carrier-frequency (PLC)
application
capacitor for harmonic-filters applications
IEC 60358-4: – , Coupling capacitor and capacitor dividers – Part 4: AC or DC single-phase
capacitor-divider and RC-divider connected between line and ground (except for CVTs which
belong to IEC 61869 series)
___________
To be published.
Under consideration.
– 6 – 60358-3 © IEC:2013
COUPLING CAPACITORS AND CAPACITOR DIVIDERS –

Part 3: AC or DC coupling capacitor
for harmonic-filters applications

1 Scope
Clause 1 of IEC 60358-1:2012 is replaced by the following:
This part of IEC 60358 applies to AC or DC single-phase coupling capacitor, with rated voltage
higher than 1 000 V, connected line to ground with the low voltage terminal either permanently
earthed or connected to a tuning device for harmonic-filters applications.
NOTE Diagrams of coupling capacitors to which this standard applies are given in Figures AA.1 and AA.2.
2 Normative references
Clause 2 of IEC 60358-1:2012 is replaced by the following:
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 60060-1:2012, High-voltage test techniques – Part 1: General definitions and test
requirements
IEC 60060-2, High-voltage test techniques – Part 2: Measuring systems
IEC 60358-1:2012, Coupling capacitors and capacitor dividers. – Part 1: General rules
IEC 60358-2, Coupling capacitors and capacitor dividers. – Part 2: AC or DC single-phase
coupling capacitor connected between line and ground for power line carrier-frequency (PLC)
application
IEC 60481, Coupling devices for power line carrier systems
IEC 61869-5, Instrument transformers – Part 5: Additional requirements for capacitive voltage
transformers
3 Terms and definitions
Clause 3 of IEC 60358-1:2012 is applicable with the following additions:
For the purposes of this document, the terms and definitions given in IEC 60358-1:2012, as
well as the following, apply.
60358-3 © IEC:2013 – 7 –
3.300 Definition for harmonic filters
3.1.1
filter capacitor
power capacitor intended to form part of a circuit designed to reduce one or more harmonic
currents present in a network
[SOURCE: IEC 60050-436:1990, 436-02-06]
3.1.2
tuning device
accessory to the capacitor to improve filtering harmonics on the network. It consists of passive
components adjusted to the filter capacitor and the frequencies to be filtered.
3.1.3
voltage limitation device
element connected between low voltage terminal of the filter capacitor and earth to limit the
overvoltages which appear across the tuning device in case of:
a) a short circuit between the high-voltage terminal and earth;
b) where an impulse voltage is applied between the high voltage terminal and earth
4 Service conditions
Clause 4 of IEC 60358-1:2012 is applicable.
5 Ratings
Clause 5 of IEC 60358-1:2012 is applicable.
6 Design requirements
Clause 6 of IEC 60358-1:2012 is applicable with the following additions:
6.2.300 Tuning device
The purchaser defines:
• The values and ratings of the components and its electrical circuit.
• The test voltages of the tuning device, however
– The 50 Hz insulation test voltage shall not be lower than 3 kV.
– The BIL test voltage shall not be lower than 10 kV.
7 Test conditions
Clause 7 of IEC 60358-1:2012 is applicable.
8 Classification of tests
Clause 8 of IEC 60358-1:2012 is applicable with the following additions:
8.2 Routine tests
Clause 8.2 of IEC 60358-1:2012 is applicable with the following additions:

– 8 – 60358-3 © IEC:2013
8.2.300 Routine test for tuning device
a) AC frequency voltage test (9.300.2.1)
b) Impedance measurement (9.300.2.2)
c) Routine voltage test for voltage limitation device (9.300.2.3)
8.3 Type tests
Clause 8.3 of IEC 60358-1:2012 is applicable with the following additions:
8.3.300 Type tests for filter capacitor and tuning device
8.3.300.1 Type tests for filter capacitor
a) High frequency capacitance and equivalent series resistance (10.300.1)
b) Measurement of the stray capacitance and stray conductance of the low voltage terminal
(10.300.2)
8.3.300.2 Type tests for tuning device
a) Impulse voltage test (10.301.1)
9 Routine tests
Clause 9 of IEC 60358-1:2012 is applicable with the following additions:
9.300 Electrical tests for coupling capacitor and tuning device
9.300.1 Routine tests for coupling capacitor
The routine tests on the capacitor part are specified in 60358-1:2012, Subclause 8.1. No
supplementary test is specified for filter capacitors.
9.300.2 Routine tests for tuning device
9.300.2.1 AC frequency voltage test
The AC-voltage is applied between protective earth and terminal (short-circuited) of the tuning
device during one minute according to Figure 300. The voltage level is defined in 6.2.300.
If the voltage limitation device is connected on protective earth, it shall be disconnected during
the test.
Neither breakdown nor flashover shall occur during the test.

60358-3 © IEC:2013 – 9 –
Tuning device with one Tuning device with two
insulated terminal insulated terminals
Tuning
Tuning
device device
~
~
Voltage circuit to
Possible short-circuit
~
connect for the test
during the voltage test
Connection to be open
Enclosure
during the voltage test
IEC  2853/13 IEC  2854/13
Figure 300 – Connection for voltage test of tuning device
9.300.2.2 Impedance measurement
A measurement of impedance at specified frequencies has to be performed; the filter capacitor
can be replaced by a capacitor model.
As acceptance criteria the purchaser shall define the maximum impedance at specified
frequencies.
Limitation device to be tested either by subsupplier or by manufacturer
9.300.2.3 Routine voltage test for voltage limitation device
The following routine test is specified according to the cases below:
a) Air-gap arrester
Measurement of the protection level voltage
The voltage AC or DC is increased until breakdown. The breakdown voltage must be within
the range specified by the manufacturer
b) Arrester
Measurement of the reference voltage of arrester
The AC voltage is increased on the arrester until the current reach 1mA rms, the measured
reference voltage must be within the range specified by the manufacturer.

– 10 – 60358-3 © IEC:2013
10 Type tests
Clause 10 of IEC 60358-1:2012 is applicable with the following additions:
10.300 Test on capacitor
10.300.1 High frequency capacitance and equivalent series resistance
The measurements shall be carried out on a capacitor stack or on a capacitor unit.
The capacitance and the equivalent series resistance shall be measured at the two
temperatures equal to the limits of the temperature category and at a temperature within the
standard range for testing (IEC 60358-1:2012, Clause 7), at frequencies specified from the
purchaser.
The purchaser specifies the measuring frequencies and the acceptance criteria in terms of
capacitance variation in function of the filter capability
The equivalent series resistance has an influence on the quality of the filter and on the thermal
withstand of the capacitor; the acceptance criteria will then be defined between purchaser and
manufacturer.
For high frequency characteristics and measuring methods, see Annex BB.
NOTE In the case of practical difficulties in carrying out the measurements at the limits of the temperature
category, the purchaser and the manufacturer may agree on measurements over a smaller temperature range, or on
measurements performed on a model capacitor containing a limited number of elements.
10.300.2 Measurement of the stray capacitance and stray conductance of the low
voltage terminal
The measurements shall be carried out either on a bottom unit or on a model representative of
the bottom part of the capacitor under consideration.
This model shall include the earth terminal, the metal parts (e.g. flanges) permanently

connected to it, and the low voltage terminal with at least one element connected to it and
placed in its proper position. If a model is used, it shall be filled with the insulating liquid used
for the capacitor.
The values of the stray capacitance and the stray conductance, measured at frequencies
specified from the purchaser, shall not exceed 200 pF and 20 µS respectively.
NOTE By low capacitance value of the filter capacitor and by different frequency range, the purchaser can ask for
lower values.
To avoid a harmful increase of the stray conductance in polluted ambient conditions, the low
voltage terminal should have a creepage distance in accordance with IEC 60358-1:2012,
Subclause 6.2.7.
10.301 Test on tuning device
10.301.1 Impulse voltage test
Five positive and five negative lightning impulses 1,2/50 µs with the test value according to
6.2.300 shall be applied on the high voltage terminal. If this, due to low resistance, is not
possible to obtain, the best possible curve with the test equipment may be accepted. In this
case, preference shall be given to retaining the front time. The tail time should however, if
possible, not be shorter than 5 µs. The other end of the tuning network shall be earthed. The

60358-3 © IEC:2013 – 11 –
protective device shall be disconnected. This test verifies the voltage withstand of the tuning
network components.
No insulation breakdown is permitted.
No significant changes in the impedance measurement (8.2.300) made before and after the
impulse test shall occur.
11 Special tests – Mechanical strength test
Clause 11 of IEC 60358-1:2012 is applicable.
12 Marking of the equipment
Clause 12 of IEC 60358-1:2012 is applicable with the following additions:
12.300 Marking of the tuning device
For the tuning device, the rating plate shall include the information given in Table 300:
Table 300 – Marking of the rating plate
No. Rating
Manufacturer’s
name or abbreviation
Indication:
Tuning device
3 Type, designation
4 Year of manufacture
5 Serial number
6 Schema
7 Components values
8 Components corresponding tolerances
Voltage limitation device
Type: (air-gap or varistor, ….)
10 Voltage limitation device Protection level voltage (1,2/50 µs or 8/20 µs or DC)

– 12 – 60358-3 © IEC:2013
Annex AA
Typical diagram of a filter capacitor
Figures AA.1 and AA.2 give examples of diagrams for a filter capacitor with and without low
voltage terminal, and with tuning device, respectively.
High voltage terminal
A A
C
C
1 1
High voltage capacitor
Earth terminal
Low voltage terminal of
coupling capacitor N
HF
IEC  2855/13
Figure AA.1 – Example of a diagram for a filter capacitor
(with and without low voltage terminal)

High voltage terminal
A
C
High voltage capacitor
Low voltage terminal of
coupling capacitor   N Earth terminal
HF
Tuning device
N
IEC  2856/13
Figure AA.2 – Example of a diagram for a filter capacitor
with tuning device
60358-3 © IEC:2013 – 13 –
Annex BB
(informative)
High-frequency characteristics of filter capacitors
BB.1 High frequency capacitance and equivalent series resistance (10.300.1)
The frequency conditions are given from the purchaser according the design of the installation.
The fact should be considered that any change in the high frequency characteristics of the
coupling capacitor, as, for instance, a change in the capacitance of the coupling capacitor itself
or the introduction of stray quantities (capacitance, etc.) may affect the filter capability.
BB.2 Stray capacitance and conductance of the low voltage terminal (10.300.2)
Stray capacitance and conductance of the low voltage terminal, with respect to the earth
terminal, should be as low as possible.
NOTE Values higher than 20 µs and/or higher than 200 pF may have an appreciable effect on the bandwidth of the
filter, at least for operation at frequencies lower than 100 kHz and for a low coupling capacitance.
Terminal design and arrangement should be chosen so that the effect of adverse atmospheric
conditions (humidity, snow, frost, dust, etc.) does not involve stray capacitance and
conductance values appreciably higher than those stated above and in Clause 10.
BB.3 Bridge method for measurement of the high frequency capacitance and
equivalent series resistance (10.300.1)
The measuring method giving the values of high-frequency capacitance and equivalent series
resistance may be chosen, as convenient, from various high frequency procedures such as
bridge methods, substitution methods, impedance analyser, etc.
It is recommended that capacitances and inductances due to the measurement connections
should be reduced as far as possible (by minimizing the length thereof) and likewise the earth
capacitances of the coupling capacitor. Particular care should be taken to screen the
measuring equipment and, if necessary, the connections.
If the stray capacitance and inductance of the measuring arrangement produce an appreciable
effect, this shall be allowed for in computing the results of the measurements.
The introduction of uncontrolled stray elements may give rise to serious errors in measuring
the capacitance.
In order to reduce to insignificant values the inductances due to the measurement connections,
it is suggested that two cages, insulated one from the other, and each made with six or eight
copper straps are used. These cages shall surround the capacitor under test and shall be in
close contact with the insulating material throughout its length. One end of the upper cage
should be connected to the line terminal, while one end of the lower cage should be connected
to the low voltage terminal. The measuring bridge should be connected with two wires as short
as possible, to the two other ends of the cages as shown in Figure BB.1.

– 14 – 60358-3 © IEC:2013
HT
LT
IEC  2857/13
HT = Line terminal
LT = Low voltage terminal
Figure BB.1 – Wiring diagram of the measuring circuit for the high frequency
capacitance and equivalent series resistance of a coupling capacitor
BB.4 Filter frequency range by case of high capacitance and long capacitor
(10.300.1)
For very high capacitance value and long capacitor, the physical self inductance of the
capacitor (typical 1µH/m) will reduce the 1st resonance frequency; in that case, the deviation of
the capacitance between the line and low voltage terminals in the sp
...