AC motor capacitors - Part 1: General - Performance, testing and rating - Safety requirements - Guidance for installation and operation (IEC 60252-1:2010)

This part of IEC 60252 applies to motor capacitors intended for connection to windings of asynchronous motors supplied from a single-phase system having a frequency up to and including 100 Hz, and to capacitors to be connected to three-phase asynchronous motors so that these motors may be supplied from a single-phase system. This standard covers impregnated or unimpregnated capacitors having a dielectric of paper, plastic film, or a combination of both, either metallized or with metal-foil electrodes, with rated voltages up to and including 660 V. Motor start capacitors are covered by IEC 60252-2. The object of this standard is a) to formulate uniform rules regarding performance, testing and rating; b) to formulate specific safety rules; c) to provide a guidance for installation and operation.

Motorkondensatoren - Teil 1: Allgemeines - Leistung, Prüfung und Bemessung - Sicherheitsanforderungen - Leitfaden für die Installation und den Betrieb (IEC 60252-1:2010)

Condensateurs des moteurs à courant alternatif - Partie 1: Généralités - Caractéristiques fonctionnelles, essais et valeurs assignées - Règles de sécurité - Lignes directrices pour l'installation et l'utilisation (CEI 60252-1:2010)

La CEI 60252-1:2010 s'applique aux condensateurs destinés à être raccordés aux enroulements des moteurs asynchrones alimentés par un réseau monophasé dont la fréquence ne dépasse pas 100 Hz, et aux condensateurs destinés aux moteurs asynchrones triphasés pour permettre le raccordement de ces moteurs à un réseau monophasé. La présente norme couvre les condensateurs imprégnés ou non, ayant un diélectrique en papier, film plastique ou une combinaison des deux, soit métallisés, soit à électrodes en feuilles de métal, pour une tension assignée n'excédant pas 660 V. Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:  - la définition de 'condensateur à film segmenté' a été ajoutée en 3.6;  - la définition de 'classes d'utilisation' a été clarifiée, avec l'ajout du concept de 'durée de vie probable' et des références aux statistiques, en 3.9;  - la phrase 'Un fonctionnement au-dessus de la tension assignée réduira la durée de vie du condensateur' a été introduite en 6.1;  - quelques clarifications ont été ajoutées dans l'Article 8: Marquage, principalement pour les petits condensateurs.

Kondenzatorji izmeničnih motorjev - 1. del: Splošno - Delovanje, preskušanje in ocenjevanje - Varnostne zahteve - Navodilo za namestitev in delovanje (IEC 60252-1:2010)

Ta del IEC 60252 velja za kondenzatorje motorjev, priklop na navitja asinhronih motorjev, napajanih iz enofaznega sistema, ki imajo frekvenco do in vključno 100 Hz, in kondenzatorje za priklop na trifazne asinhrone motorje, tako da se lahko ti motorji napajajo iz enofaznega sistema. Ta standard zajema kondenzatorje, ki so ali niso impregnirani in ki imajo dielektrik iz papirja, plastičnega filma ali kombinacije obeh, z metaliziranimi elektrodami ali elektrodami iz kovinske folije in z ocenjenimi napetostmi do in vključno 660 V. Zaganjalni kondenzatorji so zajeti v IEC 60252-2. Cilj tega standarda je a) oblikovati enotna pravila glede delovanja, preskušanja in ocenjevanja, b) oblikovati določena varnostna pravila, c) zagotoviti vodilo za inštalacijo in delovanje.

General Information

Status
Published
Publication Date
21-Feb-2011
Technical Committee
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
09-Feb-2011
Due Date
16-Apr-2011
Completion Date
22-Feb-2011

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SLOVENSKI STANDARD
SIST EN 60252-1:2011
01-april-2011
1DGRPHãþD
SIST EN 60252-1:2002
.RQGHQ]DWRUMLL]PHQLþQLKPRWRUMHYGHO6SORãQR'HORYDQMHSUHVNXãDQMHLQ
RFHQMHYDQMH9DUQRVWQH]DKWHYH1DYRGLOR]DQDPHVWLWHYLQGHORYDQMH ,(&

AC motor capacitors - Part 1: General - Performance, testing and rating - Safety
requirements - Guidance for installation and operation (IEC 60252-1:2010)
Motorkondensatoren - Teil 1: Allgemeines - Leistung, Prüfung und Bemessung -
Sicherheitsanforderungen - Leitfaden für die Installation und den Betrieb (IEC 60252-
1:2010)
Condensateurs des moteurs à courant alternatif - Partie 1: Généralités - Caractéristiques
fonctionnelles, essais et valeurs assignées - Règles de sécurité - Lignes directrices pour
l'installation et l'utilisation (CEI 60252-1:2010)
Ta slovenski standard je istoveten z: EN 60252-1:2011
ICS:
31.060.70 0RþQRVWQLNRQGHQ]DWRUML Power capacitors
SIST EN 60252-1:2011 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------

SIST EN 60252-1:2011

---------------------- Page: 2 ----------------------

SIST EN 60252-1:2011

EUROPEAN STANDARD
EN 60252-1

NORME EUROPÉENNE
February 2011
EUROPÄISCHE NORM

ICS 31.060.30; 31.060.70 Supersedes EN 60252-1:2001


English version


AC motor capacitors -
Part 1: General -
Performance, testing and rating -
Safety requirements -
Guidance for installation and operation
(IEC 60252-1:2010)


Condensateurs des moteurs à courant Motorkondensatoren -
alternatif - Teil 1: Allgemeines -
Partie 1: Généralités - Leistung, Prüfung und Bemessung -
Caractéristiques fonctionnelles, essais et Sicherheitsanforderungen -
valeurs assignées - Leitfaden für die Installation und den
Règles de sécurité - Betrieb
Lignes directrices pour l'installation et (IEC 60252-1:2010)
l'utilisation
(CEI 60252-1:2010)


This European Standard was approved by CENELEC on 2011-01-02. 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 Central Secretariat 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 Central Secretariat 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, France, Germany, Greece, Hungary, Iceland, Ireland, Italy,
Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia,
Spain, Sweden, Switzerland and the United Kingdom.
CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung

Management Centre: Avenue Marnix 17, B - 1000 Brussels


© 2011 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 60252-1:2011 E

---------------------- Page: 3 ----------------------

SIST EN 60252-1:2011
EN 60252-1:2011 - 2 -
Foreword
The text of document 33/470/FDIS, future edition 2 of IEC 60252-1, prepared by IEC TC 33, Power
capacitors, was submitted to the IEC-CENELEC parallel vote and was approved by CENELEC as
EN 60252-1 on 2011-01-02.
This European Standard supersedes EN 60252-1:2001.
This EN 60252-1:2011 includes the following significant technical changes with respect to
EN 60252-1:2001:
– the definition of “segmented capacitors” has been added, in 3.6;
– the definition of “classes of operation“ has been clarified, with the addition of the concept of “probable
life” with reference to statistics, in 3.9;
– the following wording “Operation above the rated voltage will reduce the life expectancy of the
capacitor” has been introduced in 6.1;
– some clarifications have been added to Clause 8, Marking, mainly for small capacitors.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN and CENELEC shall not be held responsible for identifying any or all such patent
rights.
The following dates were fixed:
– latest date by which the EN has to be implemented
at national level by publication of an identical
national standard or by endorsement (dop) 2011-10-02
– latest date by which the national standards conflicting
with the EN have to be withdrawn (dow) 2014-01-02
Annex ZA has been added by CENELEC.
__________
Endorsement notice
The text of the International Standard IEC 60252-1:2010 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 60110-1:1998 NOTE  Harmonized as EN 60110-1:1998 (not modified).
IEC 60143-1:2004 NOTE  Harmonized as EN 60143-1:2004 (not modified).
IEC 60252-2 NOTE  Harmonized as EN 60252-2.
IEC 60871-1:2005 NOTE  Harmonized as EN 60871-1:2005 (not modified).
IEC 60931-1:1996 NOTE  Harmonized as EN 60931-1:1996 (not modified).
IEC 61048:2006 NOTE  Harmonized as EN 61048:2006 (not modified).
IEC 61071:2007 NOTE  Harmonized as EN 61071:2007 (not modified).
__________

---------------------- Page: 4 ----------------------

SIST EN 60252-1:2011
- 3 - EN 60252-1:2011
Annex ZA
(normative)

Normative references to international publications
with their corresponding European publications

The following referenced documents are indispensable for the application 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.

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

IEC 60062 - Marking codes for resistors and capacitors EN 60062 -



IEC 60068 Series Environmental testing EN 60068 Series


IEC 60068-2-6 - Environmental testing - EN 60068-2-6 -
Part 2-6: Tests - Test Fc: Vibration
(sinusoidal)


IEC 60068-2-20 - Environmental testing - EN 60068-2-20 -
Part 2-20: Tests - Test T: Test methods for
solderability and resistance to soldering heat
of devices with leads


IEC 60068-2-21 - Environmental testing - EN 60068-2-21 -
Part 2-21: Tests - Test U: Robustness of
terminations and integral mounting devices


IEC 60068-2-78 - Environmental testing - EN 60068-2-78 -
Part 2-78: Tests - Test Cab: Damp heat,
steady state


IEC 60112 - Method for the determination of the proof and EN 60112 -
the comparative tracking indices of solid
insulating materials


IEC 60309-1 - Plugs, socket-outlets and couplers for EN 60309-1 -
industrial purposes -
Part 1: General requirements


IEC 60529 - Degrees of protection provided by enclosures - -
(IP Code)


IEC 60695-2-10 - Fire hazard testing - EN 60695-2-10 -
Part 2-10: Glowing/hot-wire based test
methods - Glow-wire apparatus and common
test procedure


IEC 60695-2-11 - Fire hazard testing - EN 60695-2-11 -
Part 2-11: Glowing/hot-wire based test
methods - Glow-wire flammability test method
for end-products


ISO 4046 - Paper, board, pulp and related terms - - -
Vocabulary

---------------------- Page: 5 ----------------------

SIST EN 60252-1:2011

---------------------- Page: 6 ----------------------

SIST EN 60252-1:2011
IEC 60252-1
®
Edition 2.0 2010-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE


AC motor capacitors –
Part 1: General – Performance, testing and rating – Safety requirements –
Guidance for installation and operation

Condensateurs des moteurs à courant alternatif –
Partie 1: Généralités – Caractéristiques fonctionnelles, essais et valeurs
assignées – Règles de sécurité – Lignes directrices pour l'installation et
l'utilisation

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
V
CODE PRIX
ICS 31.060.30; 31.060.70 ISBN 978-2-88912-189-2
® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale

---------------------- Page: 7 ----------------------

SIST EN 60252-1:2011
– 2 – 60252-1 © IEC:2010
CONTENTS
FOREWORD.4
1 Scope and object.6
2 Normative references .6
3 Terms and definitions .7
4 Service conditions .10
4.1 Normal service conditions .10
4.2 Preferred tolerances on capacitance .10
5 Quality requirements and tests .10
5.1 Test requirements .10
5.1.1 General .10
5.1.2 Test conditions .10
5.2 Nature of tests.11
5.2.1 Type tests .11
5.2.2 Routine tests .11
5.3 Type tests .11
5.3.1 Test procedure .11
5.3.2 Extent of qualification .11
5.4 Routine tests .14
5.4.1 Test procedure .14
5.5 Tangent of loss angle .14
5.6 Visual examination .14
5.7 Voltage test between terminals.14
5.8 Voltage test between terminals and case.15
5.9 Capacitance measurement .15
5.10 Check of dimensions .15
5.11 Mechanical tests .15
5.11.1 Robustness of terminations .16
5.11.2 Soldering.16
5.11.3 Vibration.17
5.11.4 Fixing bolt or stud (if fitted).17
5.12 Sealing test .17
5.13 Endurance test .18
5.13.1 Testing in air with forced circulation.18
5.13.2 Endurance test procedure.18
5.13.3 Conditions of compliance.19
5.14 Damp-heat test.19
5.15 Self-healing test .19
5.16 Destruction test .20
5.16.1 Test specimens .20
5.16.2 Test apparatus .20
5.16.3 Test procedure .22
5.16.4 Evaluation of the failure.23
5.17 Resistance to heat, fire and tracking .23
5.17.1 Ball-pressure test .23
5.17.2 Glow-wire test .23
5.17.3 Tracking test.24

---------------------- Page: 8 ----------------------

SIST EN 60252-1:2011
60252-1 © IEC:2010 – 3 –
6 Permissible overloads .24
6.1 Maximum permissible voltage.24
6.2 Maximum permissible current .24
6.3 Maximum permissible reactive output .24
7 Safety requirements .24
7.1 Creepage distances and clearances .24
7.2 Terminals and connecting cables .25
7.3 Earth connections .25
7.4 Discharge devices .26
8 Marking .26
9 Guidance for installation and operation.26
9.1 General .26
9.2 Choice of rated voltage .27
9.2.1 Measurements of working voltage.27
9.2.2 Influence of capacitance.27
9.3 Checking capacitor temperature .27
9.3.1 Choice of maximum permissible capacitor operating temperature .27
9.3.2 Choice of minimum permissible capacitor operating temperature.27
9.4 Checking transients.27
9.5 Leakage current .28
Annex A (normative) Test voltage .29
Bibliography.30

Figure 1 – Test apparatus for d.c. conditioning .21
Figure 2 – Test apparatus for a.c. destruction test .21
Figure 3 – Arrangement to produce the variable inductor L in Figure 2.22

Table 1 – Type test schedule .13
Table 2a – Test voltages.14
Table 2b – Test voltages.14
Table 3 – Torque .16
Table 4 – Endurance test conditions .19
Table 5 – Minimum creepage distances and clearances.25

---------------------- Page: 9 ----------------------

SIST EN 60252-1:2011
– 4 – 60252-1 © IEC:2010
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________

AC MOTOR CAPACITORS –

Part 1: General – Performance, testing and rating –
Safety requirements –
Guidance for installation and operation


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 60252-1 has been prepared by IEC technical committee 33: Power
capacitors and their applications.
This second edition cancels and replaces the first edition of IEC 60252-1 published in 2001
and constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
– the definition of “segmented capacitors” has been added, in 3.6;
– the definition of “classes of operation “ has been clarified, with the addition of the
concept of “probable life” with reference to statistics, in 3.9;
– the following wording “Operation above the rated voltage will reduce the life
expectancy of the capacitor” has been introduced in 6.1;

---------------------- Page: 10 ----------------------

SIST EN 60252-1:2011
60252-1 © IEC:2010 – 5 –
– some clarifications have been added to Clause 8, Marking, mainly for small capacitors.
The text of this standard is based on the following documents:
FDIS Report on voting
33/470/FDIS 33/473/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 of IEC 60252 series, under the general title AC motor capacitors can be
found on the IEC website.
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.

---------------------- Page: 11 ----------------------

SIST EN 60252-1:2011
– 6 – 60252-1 © IEC:2010
AC MOTOR CAPACITORS –

Part 1: General – Performance, testing and rating –
Safety requirements –
Guidance for installation and operation



1 Scope and object
This part of IEC 60252 applies to motor capacitors intended for connection to windings of
asynchronous motors supplied from a single-phase system having a frequency up to and
including 100 Hz, and to capacitors to be connected to three-phase asynchronous motors so
that these motors may be supplied from a single-phase system.
This standard covers impregnated or unimpregnated capacitors having a dielectric of paper,
plastic film, or a combination of both, either metallized or with metal-foil electrodes, with rated
voltages up to and including 660 V.
Motor start capacitors are covered by IEC 60252-2.
NOTE The following are excluded from this standard:
– shunt capacitors of the self-healing type for a.c. power systems of up to and including 1 000 V nominal voltage
(see IEC 60831-1);
– shunt capacitors of non-self-healing type for a.c. power systems of up to and including 1 000 V nominal voltage
(see IEC 60931-1);
– shunt capacitors for a.c. power systems having a nominal voltage above 1 000 V (see IEC 60871-1);
– capacitors for induction heat-generating plants, operating at frequencies between 40 Hz and 24 000 Hz (see
IEC 60110-1);
– series capacitors (see IEC 60143);
– coupling capacitors and capacitor dividers (see IEC 60358);
– capacitors to be used in power electronic circuits (see IEC 61071);
– small a.c. capacitors to be used for fluorescent and discharge lamps (see IEC 61048);
– capacitors for suppression of radio interference (IEC publication under consideration);
– capacitors intended to be used in various types of electrical equipment and thus considered as components;
– capacitors intended for use with d.c. voltage superimposed on a.c. voltage.
The object of this standard is
a) to formulate uniform rules regarding performance, testing and rating;
b) to formulate specific safety rules;
c) to provide a guidance for installation and operation.
2 Normative references
.The following referenced documents are indispensable for the application 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 60062, Marking codes for resistors and capacitors
IEC 60068 (all parts), Environmental testing
IEC 60068-2-6, Environmental testing – Part 2-6: Tests – Test Fc: Vibration (sinusoidal)

---------------------- Page: 12 ----------------------

SIST EN 60252-1:2011
60252-1 © IEC:2010 – 7 –
IEC 60068-2-20, Environmental testing – Part 2-20: Tests – Test T: Test methods for
solderability and resistance to soldering heat of devices with leads
IEC 60068-2-21, Environmental testing – Part 2-21: Tests – Test U: Robustness of
terminations and integral mounting devices
IEC 60068-2-78, Environmental testing – Part 2-78: Tests – Test Cab: Damp heat, steady
state
IEC 60112, Method for the determination of the proof and the comparative tracking indices of
solid insulating materials
IEC 60309-1, Plugs, socket-outlets and couplers for industrial purposes – Part 1: General
requirements
IEC 60529, Degrees of protection provided by enclosures (IP Code)
IEC 60695-2-10, Fire hazard testing – Part 2-10: Glowing/hot-wire based test methods –
Glow-wire apparatus and common test procedure
IEC 60695-2-11,Fire hazard testing – Part 2-11: Glowing/hot-wire based test methods - Glow-
wire flammability test method for end products
ISO 4046, Paper, board, pulps and related terms – Vocabulary
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
motor running capacitor
a power capacitor which, when used in conjunction with an auxiliary winding of a motor,
assists the motor to start and improves the torque under running conditions
NOTE The running capacitor is usually connected permanently to the motor winding and remains in circuit
throughout the running period of the motor. During the starting period, if it is in parallel with the starting capacitor,
it helps to start the motor.
3.2
motor starting capacitor
a power capacitor which provides a leading current to an auxiliary winding of a motor and
which is switched out of circuit once the motor is running
3.3
metal foil capacitor
a capacitor, the electrodes of which consist of metal foils or strips separated by a dielectric
3.4
metallized capacitor
a capacitor, in which the electrodes consist of a metallic deposit on the dielectric
3.5
self-healing capacitor
a capacitor, the electrical properties of which, after local breakdown of the dielectric, are
rapidly and essentially self-restored

---------------------- Page: 13 ----------------------

SIST EN 60252-1:2011
– 8 – 60252-1 © IEC:2010
3.6
segmented film capacitor
a metallised capacitor with a repeating pattern on the metallic deposit on at least one layer,
designed to isolate sections of the capacitor in the event of localised faults occurring in the
dielectric
3.7
discharge device of a capacitor
a device which may be incorporated in a capacitor, capable of reducing the voltage between
the terminals effectively to zero, within a given time, after the capacitor has been
disconnected from a network
3.8
continuous operation
operation with no time limit within the normal life of the capacitor
3.9
class of operation
the minimum probable total life for which the capacitor has been designed at rated duty,
voltage, temperature and frequency
NOTE 1 Four classes have been foreseen
Class A – 30 000 h
Class B – 10 000 h
Class C – 3 000 h
Class D – 1 000 h
These classes of operation are intended to represent a probable failure rate not exceeding 3 % during the life of
the product.
Failures considered are: short-circuits, interruptions, leakage of liquid, capacitance drifts exceeding 10 % out of the
rated tolerance limits
A capacitor may have more than one class with corresponding voltages.
NOTE 2 Classes of operation have a statistical value (the “law of big numbers”): it is not possible to transfer
automatically data coming from a limited quantity to a whole population or even to a batch of capacitors. The
purchaser and the manufacturer should agree upon to confront the case of a true failure rate larger than 3
...

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