SIST EN 60077-4:2003

Railway applications - Electric equipment for rolling stock -- Part 4: Electrotechnical components - Rules for AC circuit-breakers

Gives rules for AC circuit-breakers, the main contacts of which are to be connected to AC overhead contact lines; the nominal voltage of these circuits is in accordance with EN 60850. Complements the general requirements given in EN 60077-2.

Bahnanwendungen - Elektrische Betriebsmittel auf Bahnfahrzeugen -- Teil 4: Elektrotechnische Bauteile - Regeln für AC-Leistungsschalter

Applications ferroviaires - Equipements électriques pour le matériel roulant -- Partie 4: Composants électrotechniques - Règles pour disjoncteurs à courant monophasé

Donne les règles relatives aux disjoncteurs dont les contacts sont destinés à être connectés aux caténaires monophasées. La tension nominale de ces circuits est conforme à la EN 60850. Est un complément aux prescriptions générales données dans la EN 60077-2.

Železniške naprave – Električna oprema za vozna sredstva – 4. del: Elektrotehnične komponente – Pravila za močnostna stikala za izmenični tok (IEC 60077-4: 2003)

General Information

• Status: Published
• Publication Date: 30-Nov-2003
• ICS: 29.280 - Electric traction equipment
• Technical Committee: ŽEN - Electrical applications for railways
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 01-Dec-2003
• Due Date: 01-Dec-2003
• Completion Date: 01-Dec-2003
• Ref Project: EN 60077-4:2003 - Railway applications - Electric equipment for rolling stock - Part 4: Electrotechnical components - Rules for AC circuit-breakers

Relations

• Replaced By: SIST EN IEC 60077-4:2020 - Railway applications - Electric equipment for rolling stock - Part 4: Electrotechnical components - Rules for AC circuit-breakers
• Effective Date: 24-Dec-2019
• Revised: SIST EN IEC 60077-4:2020 - Railway applications - Electric equipment for rolling stock - Part 4: Electrotechnical components - Rules for AC circuit-breakers
• Effective Date: 27-Feb-2018

Standards Content (Sample)

SLOVENSKI SIST EN 60077-4:2003

STANDARD
december 2003
Železniške naprave – Električna oprema za vozna sredstva – 4. del:
Elektrotehnične komponente – Pravila za močnostna stikala za izmenični tok
(IEC 60077-4: 2003)
Railway applications - Electric equipment for rolling stock - Part 4: Electrotechnical
components - Rules for AC circuit-breakers (IEC 60077-4:2003)
ICS 29.280 Referenčna številka
SIST EN 60077-4:2003(en)
©  Standard je založil in izdal Slovenski inštitut za standardizacijo. Razmnoževanje ali kopiranje celote ali delov tega dokumenta ni dovoljeno

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EUROPEAN STANDARD EN 60077-4
NORME EUROPÉENNE
EUROPÄISCHE NORM May 2003

ICS 45.060


English version


Railway applications -
Electric equipment for rolling stock
Part 4: Electrotechnical components -
Rules for AC circuit-breakers
(IEC 60077-4:2003)


Applications ferroviaires -  Bahnanwendungen -
Equipements électriques pour le matériel Elektrische Betriebsmittel
roulant auf Bahnfahrzeugen
Partie 4: Composants électrotechniques - Teil 4: Elektrotechnische Bauteile -
Règles pour disjoncteurs à courant Regeln für AC-Leistungsschalter
monophasé (IEC 60077-4:2003)
(CEI 60077-4:2003)




This European Standard was approved by CENELEC on 2003-04-01. 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, Czech Republic,
Denmark, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Luxembourg, Malta,
Netherlands, Norway, Portugal, Slovakia, Spain, Sweden, Switzerland and United Kingdom.

CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung

Central Secretariat: rue de Stassart 35, B - 1050 Brussels


© 2003 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.

Ref. No. EN 60077-4:2003 E

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EN 60077-4:2003 - 2 -
Foreword
The text of document 9/718/FDIS, future edition 1 of IEC 60077-4, prepared by IEC TC 9, Electrical
equipment and systems for railways, was submitted to the IEC-CENELEC parallel vote and was
approved by CENELEC as EN 60077-4 on 2003-04-01.

This European Standard shall be read in conjunction with EN 60077-1.

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) 2004-01-01

– latest date by which the national standards conflicting
with the EN have to be withdrawn (dow) 2006-04-01

Annexes designated "normative" are part of the body of the standard.
Annexes designated "informative" are given for information only.
In this standard, annex ZA is normative and annexes A and B are informative.
Annex ZA has been added by CENELEC.
__________
Endorsement notice
The text of the International Standard IEC 60077-4 was approved by CENELEC as a European
Standard without any modification.
__________

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- 3 - EN 60077-4:2003
Annex ZA
(normative)

Normative references to international publications
with their corresponding European publications
This European Standard incorporates by dated or undated reference, provisions from other
publications. These normative references are cited at the appropriate places in the text and the
publications are listed hereafter. For dated references, subsequent amendments to or revisions of any
of these publications apply to this European Standard only when incorporated in it by amendment or
revision. For undated references the latest edition of the publication referred to applies (including
amendments).
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 60050-441 1984 International Electrotechnical - -
Vocabulary (IEV)
Chapter 441: Switchgear, controlgear
and fuses

IEC 60060-1 1989 High-voltage test techniques HD 588.1 S1 1991
+ corr. March 1990 Part 1: General definitions and test
requirements

IEC 60077-1 1999 Railway applications - Electric EN 60077-1 2002
(mod) equipment for rolling stock
Part 1: General service conditions and
general rules

IEC 60077-2 1999 Part 2: Electrotechnical components - EN 60077-2 2002
(mod) General rules

1)
IEC 60571 1998 Electronic equipment used on rail - -
vehicles

IEC 60694 1996 Common specifications for high-voltage EN 60694 1996
switchgear and controlgear standards + corr. May 1999

2)
IEC 60850 2000 Railway applications - Supply voltages - -
of traction systems

IEC 61373 1999 Railway applications - Rolling stock EN 61373 1999
equipment - Shock and vibration tests

3)
IEC 62271-100 2001 High-voltage switchgear and controlgear EN 62271-100 2001
Part 100: High-voltage alternating-
current circuit-breakers


1)
Instead of IEC 60571, the European Standard EN 50155:2001 "Railway applications - Electronic equipment used on rolling stock"
applies.
2)
Instead of IEC 60850:2000, the European Standard EN 50163:1995 (under revision) applies.
3)
IEC 62271-100 supersedes IEC 60056:1987.

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NORME CEI
INTERNATIONALE IEC
60077-4
INTERNATIONAL
Première édition
STANDARD
First edition
2003-02
Applications ferroviaires –
Equipements électriques pour le matériel roulant –
Partie 4:
Composants électrotechniques –
Règles pour disjoncteurs à courant monophasé
Railway applications –
Electric equipment for rolling stock –
Part 4:
Electrotechnical components –
Rules for AC circuit-breakers
 IEC 2003 Droits de reproduction réservés  Copyright - all rights reserved
Aucune partie de cette publication ne peut être reproduite ni No part of this publication may be reproduced or utilized in any
utilisée sous quelque forme que ce soit et par aucun procédé, form or by any means, electronic or mechanical, including
électronique ou mécanique, y compris la photocopie et les photocopying and microfilm, without permission in writing from
microfilms, sans l'accord écrit de l'éditeur. the publisher.
International Electrotechnical Commission, 3, rue de Varembé, PO Box 131, CH-1211 Geneva 20, Switzerland
Telephone: [phone] Telefax: [phone] E-mail: [e-mail]  Web: www.iec.ch
CODE PRIX
T
Commission Electrotechnique Internationale PRICE CODE
International Electrotechnical Commission
Международная Электротехническая Комиссия
Pour prix, voir catalogue en vigueur
For price, see current catalogue

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60077-4  IEC:2003 – 3 –
CONTENTS
FOREWORD . 5
INTRODUCTION .7
1 Scope . 9
2 Normative references.11
3 Definitions.11
3.1 Components .11
3.2 Component parts .13
3.3 Operational features .15
3.4 Making and breaking characteristics – see Annex B .17
4 Classification .19
5 Characteristics.21
5.1 Summary of characteristics .21
5.2 Type of circuit-breaker .21
5.3 Rated values and limiting values for the main circuit.21
5.4 Operational frequencies .25
5.5 Electric and pneumatic control circuits.25
5.6 Electric and pneumatic auxiliary circuits .25
5.7 Over-current release .27
5.8 Recovery voltages.27
6 Product information.27
6.1 Component documentation.27
6.2 Marking .27
7 Normal service conditions .27
8 Constructional and performance requirements.27
8.1 Constructional requirements.27
8.2 Performance requirements .27
9 Tests .31
9.1 Kind of tests.31
9.2 Tests for verification of constructional requirements .33
9.3 Type tests for verification of performance requirements.33
9.4 Routine tests for verification of performance requirements .45
Annex A (informative) Test circuit to verify the making and breaking capacities .47
Annex B (informative) Determination of short-circuit making and breaking currents,
and of percentage DC component.49
Figure A.1 – Principle of test circuit .47
Figure B.1 – Determination of short-circuit making and breaking currents, and of
percentage DC components.49
Table 1 – Operational performance capability .29
Table 2 – List of type test sequences for performance requirements .35
Table 3 – Tolerances on test values .37
Table 4 – Determination of voltage for impulse test.37

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60077-4  IEC:2003 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
___________
RAILWAY APPLICATIONS –
ELECTRIC EQUIPMENT FOR ROLLING STOCK –
Part 4: Electrotechnical components –
Rules for AC circuit-breakers
FOREWORD
1) The IEC (International Electrotechnical Commission) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of the 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, the IEC publishes International Standards. 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. The 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 the 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 National Committees.
3) The documents produced have the form of recommendations for international use and are published in the form
of standards, technical specifications, technical reports or guides and they are accepted by the National
Committees in that sense.
4) In order to promote international unification, IEC National Committees undertake to apply IEC International
Standards transparently to the maximum extent possible in their national and regional standards. Any
divergence between the IEC Standard and the corresponding national or regional standard shall be clearly
indicated in the latter.
5) The IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with one of its standards.
6) Attention is drawn to the possibility that some of the elements of this International Standard may be the subject
of patent rights. The IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 60077-4 has been prepared by IEC technical committee 9: Electrical
equipment and systems for railways.
This standard should be read in conjunction with IEC 60077-1.
The text of this standard is based on the following documents:
FDIS Reports on voting
9/718/FDIS 9/735/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.
The committee has decided that the contents of this publication will remain unchanged until 2010.
At this date, the publication will be
• reconfirmed;
• withdrawn;
• replaced by a revised edition, or
• amended.

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60077-4  IEC:2003 – 7 –
INTRODUCTION
This International Standard is Part 4 of the IEC 60077 series.
The purpose of this product standard is to give additional or amended requirements on AC
circuit-breakers as a supplement to those given by IEC 60077-2.
During preparation of this product standard, IEC 60056 and IEC 60694 have been considered
and their requirements have been kept as far as it has been possible.
This product standard makes reference to the general rules for electrotechnical components
given in IEC 60077-2, but for general conditions reference is made directly to IEC 60077-1.

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60077-4  IEC:2003 – 9 –
RAILWAY APPLICATIONS –
ELECTRIC EQUIPMENT FOR ROLLING STOCK –
Part 4: Electrotechnical components –
Rules for AC circuit-breakers
1 Scope
In addition to the general requirements of IEC 60077-2, this part of IEC 60077 gives rules for
AC circuit-breakers, the main contacts of which are to be connected to AC overhead contact
lines; the nominal voltage of these circuits being in accordance with IEC 60850.
This standard, together with IEC 60077-2, states specifically:
a) the characteristics of the circuit-breakers;
b) the service conditions with which circuit-breakers have to comply with reference to:
– operation and behaviour in normal service,
– operation and behaviour in short-circuit,
– dielectric properties;
c) the tests for confirming the compliance of the components with the characteristics under
the service conditions and the methods to be adopted for these tests;
d) the information to be marked on, or given with the circuit-breaker.
NOTE 1 Circuit-breakers which are dealt with in this standard may be provided with devices for automatic opening
under pre-determined conditions other than those of over-current, for example, undervoltage and reversal of power
current. This standard does not deal with the verification of operation under such predetermined conditions.
NOTE 2 The incorporation of electronic components or electronic sub-assemblies into electrotechnical compo-
nents is now common practice.
Although this standard is not applicable to electronic equipment, the presence of electronic components does not
provide a reason to exclude such electrotechnical components from the scope.
Electronic sub-assemblies included in the circuit-breakers should comply with the relevant standard for electronics
(IEC 60571).
NOTE 3 Certain of these rules may, after agreement between user and manufacturer, be used for electrotechnical
components installed on vehicles other than rail rolling stock.
This standard does not cover industrial circuit-breakers which have to comply with IEC 60056.
For these, in order to ensure satisfactory operation, this standard should be used to specify
only the particular requirements for rolling stock. In such cases, a specific document should
state the additional requirements with which the industrial circuit-breakers are to comply, for
example:
– either to be adapted (e.g. for control voltage, environmental conditions, etc.);
– or to be installed and used so that they do not have to endure specific rolling stock
conditions;
– or to be additionally tested to prove that these components can withstand satisfactorily the
rolling stock conditions.

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60077-4  IEC:2003 – 11 –
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 60050(441):1984, International Electrotechnical Vocabulary (IEV) – Chapter 441:
Switchgear, controlgear and Fuses
*
IEC 60056:2001, High voltage alternating-current circuit-breaker
IEC 60060-1:1989, High voltage test techniques – General definitions and test requirements
IEC 60077-1:1999, Railway applications – Electric equipment for rolling stock. – Part 1:
General service conditions and general rules
IEC 60077-2:1999, Railway applications – Electric equipment for rolling stock. – Part 2:
Electrotechnical components – General rules
IEC 60571:1998, Railway applications – Electronic equipment used on rail vehicles
IEC 60694:1996, Common specification for high voltage switchgear and controlgear standards
IEC 60850:2000, Supply voltage of traction systems
IEC 61373:1999, Railway applications – Rolling stock equipment – Shock and Vibration test
IEC 62271-100:2001, High-voltage switchgear and controlgear – Part 100: High-voltage
alternating-current circuit-breakers
3 Definitions
For the purposes of this of IEC 60077, the definitions given in clause 3 of IEC 60077-1 and
clause 3 of IEC 60077-2 are applicable together with the following additional definitions.
3.1 Components
3.1.1
indoor circuit-breaker
circuit-breaker designed solely for protected installation against wind, rain, snow, abnormal dirt
deposits, abnormal conditions, ice and hoar-frost
[IEV 441-11-04, modified]
3.1.2
outdoor circuit-breaker
circuit-breaker suitable for installation in open air, i.e. capable of withstanding wind, rain, snow,
dirt deposits, condensation, ice and hoarfrost
[IEV 441-11-05, modified]
___________
*
 In preparation.

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60077-4  IEC:2003 – 13 –
3.1.3
oil circuit-breaker
circuit-breaker in which the contacts open and close in oil
[IEV 441-14-28]
NOTE Typical examples of oil circuit-breakers are live tank minimum oil circuit-breakers and dead tank bulk oil
circuit-breakers.
3.1.4
vacuum circuit-breaker
circuit-breaker in which the contacts open and close within a highly evacuated envelope
[IEV 441-14-29]
3.1.5
air-blast circuit-breaker
circuit-breaker in which the contacts open in a blast of air
[IEV 441-14-32, modified]
3.1.6
gas circuit-breaker
circuit-breaker in which the contacts open and close in a gas other than air at atmospheric or
higher pressure
NOTE An example of a gas circuit-breaker is the sulphur hexafluoride circuit-breaker.
3.1.7
semi-conductor circuit-breaker
circuit-breaker whose operation is produced by means of semi-conductors inserted into the
main circuit in association with contacts
3.2 Component parts
3.2.1
release
device which releases the holding means and permits the opening or closing of the circuit-
breaker
NOTE 1 A circuit-breaker may be activated by several releases each becoming operational according to specified
conditions.
NOTE 2 These releases may be mechanically or electrically connected to the switching device.
3.2.1.1
over-current (instantaneous) release
device which causes a tripping operation without any intentional time delay when the current
exceeds a specified value
[IEV 441-16-32, modified]
3.2.1.2
definite time-delay over-current release
over-current release which operates with a definite time-delay which may be adjustable, but is
independent of the value of the over-current
[IEV 441-16-34]
3.2.1.3
direct over-current release
over-current release directly energised by the current in the main circuit of the circuit-breaker
[IEV 441-16-36, modified]

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60077-4  IEC:2003 – 15 –
3.2.1.4
indirect over-current release
over-current release initiated by the current in the main circuit through a current sensor
(transformer or current transducer)
[IEV 441-16-37, modified]
3.2.2
anti-pumping device
device which prevents reclosing after a close-open operation as long as the device initiating
closing is maintained in the position for closing
[IEV 441-16-48]
NOTE The opening operation may be either an opening command or a tripping operation.
3.2.3
enclosure
part providing a specified degree of protection for the circuit-breaker against external pollution
and a specified degree of protection against access to live parts and moving parts. The
enclosure may also provide a protection of adjacent parts against the influence of the circuit-
breaker (e.g. arcing)
[IEV 441-13-01, modified]
3.2.4
integral enclosure
enclosure forming an integral part of the circuit-breaker
3.3 Operational features
3.3.1
trip free circuit-breaker
circuit-breaker, the moving main contacts of which return to and remain in the open position
when the opening (i.e. tripping) operation is initiated after the initiation of the closing operation
even if the closing command is maintained
[IEV 441-16-31, modified]
NOTE 1 To ensure satisfactory breaking of the current after initiation of a closing command, it may be necessary
that the contacts momentarily reach the closed position.
NOTE 2 The trip free operation may require an anti-pumping device.
3.3.2
current setting
value of current in the main circuit to which the operating characteristics of the over-current
release are referred and for which the release is set
[IEV 441-16-46, modified]
NOTE A release may have more than one current setting.
3.3.3
tripping operation
opening operation of a circuit-breaker initiated by a release

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60077-4  IEC:2003 – 17 –
3.4 Making and breaking characteristics – see Annex B
3.4.1
opening time
interval of time between the specified instant of initiation of the opening operation and the
instant when the arcing contacts have separated
[IEV 441-17-36, modified]
NOTE The opening time includes the operating time of any auxiliary equipment necessary to open the circuit-
breaker and forming an integral part of the circuit-breaker.
3.4.2
prospective current
current that would flow in the circuit if the circuit-breaker were replaced by a conductor of
negligible impedance
[IEV 441-17-01, modified]
NOTE 1 This term is commonly associated with fault conditions.
NOTE 2 The prospective current is composed of an RMS AC value plus a DC component (if any).
3.4.3
prospective peak current
peak value of a prospective current during the transient period following initiation
[IEV 441-17-02]
3.4.4
prospective symmetrical current (of an AC circuit)
prospective current when it is initiated at such an instant that no transient phenomenon follows
the initiation
[IEV 441-17-03]
NOTE The prospective symmetrical current is expressed by its RMS value.
3.4.5
maximum prospective peak current (of an AC circuit)
prospective peak current when initiation of the current takes place at the instant which leads to
the highest possible value
[IEV 441-17-04]
3.4.6
breaking current
the current in a circuit-breaker at the instant of initiation of the arc during a breaking process
[IEV 441-17-07, modified]
3.4.7
breaking capacity
value of prospective current that a circuit-breaker is capable of breaking at a stated voltage
under prescribed conditions of use and behaviour
[IEV 441-17-08, modified]
3.4.8
making capacity
value of prospective current that a circuit-breaker is capable of making at a stated voltage
under prescribed conditions of use and behaviour
[IEV 441-17-09, modified]

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60077-4  IEC:2003 – 19 –
3.4.9
short-circuit making capacity
making capacity for which the prescribed conditions include a short-circuit
[IEV 441-17-10, modified]
3.4.10
short-circuit breaking capacity
breaking capacity for which the prescribed conditions include a short-circuit
[IEV 441-17-11, modified]
3.4.11
short time withstand current
current that a circuit-breaker in the closed position can carry during a specified short time
under specified conditions of use and behaviour
[IEV 441-17-17, modified]
3.4.12
peak withstand current
value of peak current that a circuit-breaker in the closed position can withstand under
prescribed conditions of use and behaviour
[IEV 441-17-18, modified]
3.4.13
recovery voltage
the voltage which appears across the terminals of a circuit-breaker after breaking of the current
[IEV 441-17-25, modified]
NOTE This voltage may be considered in two successive intervals of time, one during which a transient voltage
exists, followed by a second one during which the power frequency or the steady-sate recovery voltage alone exists.
3.4.14
transient recovery voltage
recovery voltage during the time in which it has a significant transient character
[IEV 441-17-26]
NOTE 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.
3.4.15
power frequency recovery voltage
recovery voltage after the transient voltage phenomena have subsided
[IEV 441-17-27]
4 Classification
This clause is intended to list the characteristics of a circuit-breaker on which information is
given by the manufacturer and which shall be verified by testing where relevant.
The circuit-breakers are classified:
– according to their operational frequency C1, C2 or C3. The characteristics of these
operational frequencies are given in 5.4;
– according to the type of design, i.e. outdoor or indoor circuit-breaker.

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60077-4  IEC:2003 – 21 –
5 Characteristics
5.1 Summary of characteristics
The characteristics of a circuit-breaker shall be stated in terms of the following, as applicable:
– type of circuit-breaker (5.2);
– rated values and limiting values for the main circuit (5.3);
– operational frequencies (5.4);
– electric and pneumatic control circuits (5.5);
– electric and pneumatic auxiliary circuits (5.6);
– over-current releases (5.7);
– peak value of the recovery voltage (5.8).
5.2 Type of circuit-breaker
It is necessary to state:
– the kind of device (e.g. air blast circuit-breaker, vacuum circuit-breaker, gas circuit-breaker,
oil circuit-breaker, semiconductor circuit-breaker, etc.);
– the type of design (see Clause 4);
– the degree of protection provided by the enclosure (see Clause 4);
– operational features (e.g. trip-free circuit-breaker direct or indirect over-current release,
time delay over-current release).
5.3 Rated values and limiting values for the main circuit
5.3.1 General
Rated values are assigned by the manufacturer but it is not necessary to establish all the
ratings listed.
5.3.2 Rated voltages
The rated voltages for a circuit-breaker are the following:
– rated operational voltage (U ), (see 5.1.2 of IEC 60077-1);
e
NOTE A circuit-breaker may have more than one rated operational voltage or may
...