EN 60077-1:2017

SLOVENSKI STANDARD
01-oktober-2018
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SIST EN 60077-1:2003
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Railway applications - Electric equipment for rolling stock - Part 1: General service
conditions and general rules
Bahnanwendungen - Elektrische Betriebsmittel auf Bahnfahrzeugen - Teil 1: Allgemeine
Betriebsbedingungen und allgemeine Regeln
Applications ferroviaires - Equipements électriques du matériel roulant - Partie 1:
Conditions générales de service et règles générales
Ta slovenski standard je istoveten z: EN 60077-1:2017
ICS:
29.280 (OHNWULþQDYOHþQDRSUHPD Electric traction equipment
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN 60077-1
NORME EUROPÉENNE
EUROPÄISCHE NORM
November 2017
ICS 45.060.01 Supersedes EN 60077-1:2002
English Version
Railway applications - Electric equipment for rolling stock -
Part 1: General service conditions and general rules
(IEC 60077-1:2017)
Applications ferroviaires - Equipements électriques du Bahnanwendungen - Elektrische Betriebsmittel auf
matériel roulant - Partie 1: Conditions générales de service Bahnfahrzeugen - Teil 1: Allgemeine Betriebsbedingungen
et règles générales und allgemeine Regeln
(IEC 60077-1:2017) (IEC 60077-1:2017)
This European Standard was approved by CENELEC on 2017-09-04. CENELEC members are bound to comply with the CEN/CENELEC
Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.
Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC
Management Centre or to any CENELEC member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the
same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden,
Switzerland, Turkey and the United Kingdom.

European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2017 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN 60077-1:2017 E
European foreword
The text of document 9/2266/FDIS, future edition 2 of IEC 60077-1, prepared by IEC/TC 9 "Electrical
equipment and systems for railways" was submitted to the IEC-CENELEC parallel vote and approved
by CENELEC as EN 60077-1:2017.

The following dates are fixed:
(dop) 2018-06-04
• latest date by which the document has to be
implemented at national level by
publication of an identical national
standard or by endorsement
• latest date by which the national (dow) 2020-09-04
standards conflicting with the
document have to be withdrawn
This document supersedes EN 60077-1:2002.

Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights.

Endorsement notice
The text of the International Standard IEC 60077-1:2017 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 60071-1 NOTE Harmonized as EN 60071-1.
IEC 60077-2 NOTE Harmonized as EN 60077-2.
IEC 60077-3 NOTE Harmonized as EN 60077-3.
IEC 60077-4 NOTE Harmonized as EN 60077-4.
IEC 60077-5 NOTE Harmonized as EN 60077-5.
IEC 60112 NOTE Harmonized as EN 60112.
IEC 60216-5 NOTE Harmonized as EN 60216-5.
IEC 60310:2016 NOTE Harmonized as EN 60310:2016 (not modified).
IEC 60322 NOTE Harmonized as EN 60322.
IEC 60364-4-41 NOTE Harmonized as HD 60364-4-41.
IEC 60587 NOTE Harmonized as EN 60587.
IEC 60664-1 NOTE Harmonized as EN 60664-1.
IEC 61140 NOTE Harmonized as EN 61140.
IEC 62271-100:2008 NOTE Harmonized as EN 62271-100:2009 (not modified).
IEC 62271-100:2008/A1:2012 NOTE Harmonized as EN 62271-100:2009/A1:2012 (not modified).
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications

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.
NOTE 1  Where an International Publication has been modified by common modifications, indicated by (mod), the relevant
EN/HD applies.
NOTE 2  Up-to-date information on the latest versions of the European Standards listed in this annex is available here:
www.cenelec.eu.
Publication Year Title EN/HD Year

IEC 60068-2-1 -  Environmental testing - Part 2-1: Tests - EN 60068-2-1 -
Test A: Cold
IEC 60068-2-2 -  Environmental testing - Part 2-2: Tests - EN 60068-2-2 -
Test B: Dry heat
IEC 60068-2-30 -  Environmental testing - Part 2-30: Tests - EN 60068-2-30 -
Test Db: Damp heat, cyclic (12 h + 12 h
cycle)
IEC 60068-2-52 -  Environmental testing - Part 2-52: Tests - EN 60068-2-52 -
Test Kb: Salt mist, cyclic (sodium chloride
solution)
IEC 60068-2-78 -  Environmental testing - Part 2-78: Tests - EN 60068-2-78 -
Test Cab: Damp heat, steady state
IEC 60085 -  Electrical insulation - Thermal evaluation EN 60085 -
and designation
IEC 60216-1 -  Electrical insulating materials - Thermal EN 60216-1 -
endurance properties - Part 1: Ageing
procedures and evaluation of test results
IEC 60505 -  Evaluation and qualification of electrical EN 60505 -
insulation systems
IEC 60529 -  Degrees of protection provided by EN 60529 -
enclosures (IP Code)
IEC 60721-3-5 -  Classification of environmental conditions - EN 60721-3-5 -
Part 3: Classification of groups of
environmental parameters and their
severities - Section 5: Ground vehicle
installations
IEC 60850 -  Railway applications - Supply voltages of - -
traction systems
IEC 61133 2016 Railway applications - Rolling stock - - -
Testing of rolling stock on completion of
construction and before entry into service
Publication Year Title EN/HD Year

IEC 61373 -  Railway applications - Rolling stock EN 61373 -
equipment - Shock and vibration tests
IEC 61991 -  Railway applications - Rolling stock - - -
Protective provisions against electrical
hazards
IEC 61992-1 -  Railway applications - Fixed installations - - -
DC switchgear - Part 1: General
IEC 62236-3-2 -  Railway applications - Electromagnetic - -
compatibility - Part 3-2: Rolling stock -
Apparatus
IEC 62497-1 -  Railway applications - Insulation - -
coordination - Part 1: Basic requirements -
Clearances and creepage distances for all
electrical and electronic equipment
IEC 62498-1 2010 Railway applications - Environmental - -
conditions for equipment -
Part 1: Equipment on board rolling stock

IEC 60077-1 ®
Edition 2.0 2017-07
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Railway applications – Electric equipment for rolling stock –

Part 1: General service conditions and general rules

Applications ferroviaires – Equipements électriques du matériel roulant –

Partie 1: Conditions générales de service et règles générales

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 45.060.01 ISBN 978-2-8322-4422-7

– 2 – IEC 60077-1:2017 © IEC 2017
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 8
2 Normative references . 8
3 Terms, definitions and abbreviated terms (see also Annex A) . 9
3.1 General . 9
3.2 Circuits . 10
3.3 Battery supplied equipment . 10
3.4 Test categories . 11
3.5 Characteristic quantities . 11
3.6 Terms related to lifetime . 12
3.7 Abbreviated terms . 13
4 Classification . 13
5 Characteristics of the utilization category . 13
5.1 General . 13
5.2 Rated voltages . 13
5.2.1 General . 13
5.2.2 Rated operational voltage (U ) . 13
r
5.2.3 Rated insulation voltage (U ) . 13
Nm
5.2.4 Power-frequency test voltage (U ) . 14
a
5.2.5 Rated impulse voltage (U ) . 14
Ni
5.3 Rated voltages for electric equipment . 14
5.3.1 Equipment supplied by a contact line . 14
5.3.2 Equipment supplied by a transformer . 14
5.3.3 Equipment supplied by DC low voltage sources . 14
5.4 Rated currents for equipment . 15
5.4.1 Rated operational current (I ) . 15
r
5.4.2 Rated short-time withstand current (I ) . 15
cw
5.5 Rated operational frequency (f ). 15
r
5.6 Rated air pressure . 16
6 Product information . 16
6.1 Nature of information . 16
6.2 Marking . 16
6.3 Instructions for storage, installation, operation and maintenance . 17
7 Normal service conditions . 17
7.1 General . 17
7.2 Altitude . 17
7.3 Temperature . 18
7.3.1 Ambient temperature . 18
7.3.2 Reference temperature . 18
7.4 Humidity . 19
7.5 Biological conditions . 19
7.6 Chemically active substances . 19
7.7 Mechanically active substances . 19
7.8 Vibration and shock . 19

IEC 60077-1:2017 © IEC 2017 – 3 –
7.9 Exposure to pollution . 19
7.10 Exposure to overvoltages . 19
8 Constructional and performance requirements . 19
8.1 Constructional requirements . 19
8.1.1 Protective provisions against electrical hazards . 19
8.1.2 Batteries . 20
8.1.3 Fire protection . 20
8.1.4 Other risks . 20
8.2 Performance requirements . 20
8.2.1 Operating conditions . 20
8.2.2 Temperature limits . 22
8.2.3 Operation following inactivity . 26
8.2.4 Electromagnetic compatibility (EMC) . 27
8.2.5 Acoustic noise emission . 27
8.2.6 Clearances . 27
8.2.7 Creepage distances . 27
8.2.8 Switching overvoltages . 27
8.2.9 Operational performance . 27
8.2.10 Ability to withstand vibration and shock . 28
9 Tests . 28
9.1 Kinds of tests . 28
9.1.1 General . 28
9.1.2 Type tests. 28
9.1.3 Routine tests . 28
9.1.4 Sampling tests . 29
9.1.5 Investigation tests. 29
9.1.6 General test condition . 29
9.1.7 Summary of tests . 29
9.2 Verification of constructional requirements . 30
9.2.1 General . 30
9.2.2 Type tests. 30
9.2.3 Routine tests . 31
9.3 Verification of performance requirements . 31
9.3.1 Operating limits and functional tests . 31
9.3.2 Temperature rise test . 32
9.3.3 Dielectric properties . 35
9.3.4 Operational performance capability. 36
9.3.5 Vibration and shock . 39
9.3.6 Electromagnetic compatibility (EMC) . 39
9.3.7 Acoustic noise emission . 39
9.3.8 Climatic tests . 39
Annex A (informative) Coordination between definitions . 40
Annex B (informative) Type and routine test of dielectric tests for equipment . 42
B.1 General . 42
B.2 General conditions . 42
B.3 Test voltage . 42
Annex C (informative) Example of thermal endurance calculation to demonstrate the
suitability of an insulation system for a specified application . 45

– 4 – IEC 60077-1:2017 © IEC 2017
C.1 General . 45
C.2 Example 1 – Temperature limits for an electric insulation system . 45
C.3 Example 2 – Thermal endurance calculation . 46
C.3.1 General . 46
C.3.2 Operating conditions provided by the purchaser . 46
C.3.3 Thermal endurance characteristics provided by the manufacturer . 47
C.3.4 Temperature rise test results . 47
C.3.5 Extrapolations . 47
C.3.6 Lifetime calculation based on thermal endurance . 48
C.3.7 Equivalent continuous duty and rated continuous duty . 49
Bibliography . 50

Figure A.1 – Example of relation of limiting values . 41
Figure A.2 – Example of utilization category . 41
Figure A.3 – Example of coordination of operational conditions . 41

Table 1 – Voltage ranges for control circuits and auxiliary circuits. 15
Table 2 – Classes of air temperatures . 18
Table 3 – Temperature limits of electrical insulating system . 24
Table 4 – Temperature limits of terminals . 25
Table 5 – Temperature limits of accessible parts . 26
Table 6 – List of tests (as appropriate) . 30
Table B.1 – Dielectric tests on single pieces of equipment . 43
Table B.2 – Dielectric tests for equipment connected to AC contact line . 44
Table C.1 – Temperature limits and expected lifetime for a dry-type insulation system
(examples) . 46
Table C.2 – Ambient temperature distribution . 47
Table C.3 – Temperature rise test results . 47
Table C.4 – Extrapolation to other ambient temperature . 48
Table C.5 – Lifetime calculation based on thermal endurance . 48
Table C.6 – Equivalent continuous duty and rated continuous duty . 49

IEC 60077-1:2017 © IEC 2017 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
RAILWAY APPLICATIONS –
ELECTRIC EQUIPMENT FOR ROLLING STOCK –

Part 1: General service conditions and general rules

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 60077-1 has been prepared by IEC technical committee 9:
Electrical equipment and systems for railways.
This second edition cancels and replaces the first edition of IEC 60077-1, issued in 1999. It
constitutes a technical revision.
This edition includes the following main technical changes with regard to the previous edition:
a) Descriptions regarding insulation coordination, environmental conditions and those of
current return and protective bonding are deleted and replaced by references to
IEC 62497-1, IEC 62498-1 and IEC 61991, except classes of air temperature, which are
copied from Table 2 in IEC 62498-1:2010.
b) Classification of equipment type is introduced.
c) Temperature limits and temperature rise tests are reviewed.

– 6 – IEC 60077-1:2017 © IEC 2017
d) Example of lifetime calculation: Annex C (informative) is introduced.
The text of this standard is based on the following documents:
FDIS Report on voting
9/2266/FDIS 9/2278/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts in the IEC 60077 series, published under the general title Railway
applications – Electric equipment for rolling stock, 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 website 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.
IEC 60077-1:2017 © IEC 2017 – 7 –
INTRODUCTION
Although this document specifies the general service conditions and general rules for electric
equipment for railway rolling stock, further details for certain types of electric equipment may
be given in other IEC standards.
IEC 60077 series consists of the following parts:
• Part 1 – General service conditions and general rules
• Part 2 – Electrotechnical components – General rules
• Part 3 – Electrotechnical components – Rules for DC circuit-breakers
• Part 4 – Electrotechnical components – Rules for AC circuit-breakers
• Part 5 – Electrotechnical components – Rules for HV fuses
Although all circuits of power or control electronic equipment connected to battery or contact
line are covered by this document, internal circuits of these may be subject to special
requirements covered by relevant product standards.
For electric equipment for rolling stock which conforms to an appropriate international
standard, including items of industrial equipment, this document, plus the relevant equipment
product standard for electric equipment where appropriate, specifies only those additional
requirements to ensure satisfactory operation on rolling stock.

– 8 – IEC 60077-1:2017 © IEC 2017
RAILWAY APPLICATIONS –
ELECTRIC EQUIPMENT FOR ROLLING STOCK –

Part 1: General service conditions and general rules

1 Scope
This part of IEC 60077 specifies the general service conditions and requirements for all
electric equipment installed in power circuits, auxiliary circuits, control and indicating circuits
etc., on railway rolling stock.
NOTE Some of these rules can, after agreement between the user and the manufacturer, be used for electrical
equipment installed on vehicles other than railway rolling stock, such as mine locomotives, trolley buses, etc.
The purpose of this document is to harmonize as far as practicable all rules and requirements
of a general nature applicable to electric equipment for rolling stock. This is in order to obtain
uniformity of requirements and tests throughout the corresponding range of equipment to
avoid the need for testing to different standards.
All requirements relating to:
• the environmental stresses expected during the normal service conditions;
• the construction;
• the performance and the associated tests which can be considered as general;
have therefore been gathered in this document together with specific subjects of wide interest
and application, for example temperature rise, dielectric properties, etc.
In the event of there being a difference in requirements between this document and a railway
rolling stock relevant product standard, then the product standard requirements take
precedence.
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 60068-2-1, Environmental testing – Part 2-1: Tests – Tests A: Cold
IEC 60068-2-2, Environmental testing – Part 2-2: Tests – Tests B: Dry heat
IEC 60068-2-30, Environmental testing – Part 2-30: Tests – Test Db: Damp heat, cyclic
(12 h + 12 h cycle)
IEC 60068-2-52, Environmental testing – Part 2-52: Tests – Test Kb: Salt mist, cyclic (sodium
chloride solution)
IEC 60068-2-78, Environmental testing – Part 2-78: Tests – Test Cab: Damp heat, steady
state
IEC 60085, Electrical insulation – Thermal evaluation and designation

IEC 60077-1:2017 © IEC 2017 – 9 –
IEC 60216-1, Electrical insulating materials – Thermal endurance properties – Part 1: Ageing
procedures and evaluation of test results
IEC 60505, Evaluation and qualification of electrical insulation systems
IEC 60529, Degrees of protection provided by enclosures (IP Code)
IEC 60721-3-5, Classification of environmental conditions – Part 3: Classification of groups of
environmental parameters and their severities – Section 5: Ground vehicle installations
IEC 60850, Railway applications – Supply voltages of traction systems
IEC 61133:2016, Railway applications – Rolling stock – Testing of rolling stock on completion
of construction and before entry into service
IEC 61373, Railway applications – Rolling stock equipment – Shock and vibration tests
IEC 61991, Railway applications – Rolling stock – Protective provisions against electrical
hazards
IEC 61992-1, Railway applications – Fixed installations – DC switchgear – Part 1: General
IEC 62236-3-2, Railway applications – Electromagnetic compatibility – Part 3-2: Rolling stock
– Apparatus
IEC 62497-1, Railway applications – Insulation coordination – Part 1: Basic requirements –
Clearances and creepage distances for all electrical and electronic equipment
IEC 62498-1:2010, Railway applications – Environmental conditions for equipment – Part 1:
Equipment on board rolling stock
3 Terms, definitions and abbreviated terms (see also Annex A)
For the purposes of this document, the following terms and definitions 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 General
3.1.1
rolling stock
all the vehicles with or without motors
Note 1 to entry: Examples of vehicles include a locomotive, a coach and a wagon.
[SOURCE: IEC 60050-811:2017, 811-02-01]
3.1.2
vehicle
single item of rolling stock
– 10 – IEC 60077-1:2017 © IEC 2017
3.2 Circuits
3.2.1
power circuit
circuit carrying the current of the machines and equipment, such as the converters and
traction motors, which transmit the traction output
[SOURCE: IEC 60050-811:2017, 811-25-03]
3.2.2
main circuit
all the conductive parts of a device carrying the current for the function to which this device
has been applied
3.2.3
auxiliary circuit,
circuit carrying the current of the auxiliaries such as the compressors and fans
[SOURCE: IEC 60050-811:2017, 811-25-05]
3.2.4
control circuit,
circuit used to actuate the power or auxiliary equipment
[SOURCE: IEC 60050-811:2017, 811-25-12]
3.2.5
indicating circuit
circuit transmitting a signal indicating or recording whether a particular operating condition
exists or not (for example a signal indicating a failure in the electrical equipment)
[SOURCE: IEC 60050-811:2017, 811-25-14]
3.3 Battery supplied equipment
3.3.1
battery
electrochemical system capable of storing in chemical form the electric energy received and
which can give it back by reconversion
3.3.2
battery on float
secondary battery whose terminals are permanently connected to a source of constant
voltage sufficient to maintain the battery approximately fully charged, and which is intended to
supply power to an electric circuit, if the normal supply is temporarily interrupted
Note 1 to entry: The battery is absorbing a float charge current in this mode.
[SOURCE: IEC 60050-482:2004, 482-05-35, modified – Note 1 to entry has been added.]
3.3.3
float charge battery system
equipment mostly operated with the battery on float charge
3.3.4
battery off charge system
equipment mostly supplied while the battery is not being charged

IEC 60077-1:2017 © IEC 2017 – 11 –
3.4 Test categories
3.4.1
type test
conformity test made on one or more items representative of the production
[SOURCE: IEC 60050-811:2017, 811-10-04]
3.4.2
routine test
conformity test made on each individual item during or after manufacture
[SOURCE: IEC 60050-811:2017, 811-10-05]
3.4.3
sampling test
test on a sample
[SOURCE: IEC 60050-811:2017, 811-10-06]
3.4.4
investigation test
special test of an optional character carried out in order to obtain additional information
[SOURCE: IEC 60050-811:2017, 811-10-07]
3.4.5
exposed conductive part
conductive part which can readily be touched and which is not normally alive, but which may
become alive under fault conditions
[SOURCE: IEC 60050-441:1984, 441-11-10, modified – Note has been deleted.]
3.5 Characteristic quantities
3.5.1
limiting value
greatest or smallest admissible value of a quantity in a specification of a component, device,
equipment, or system
[SOURCE: IEC 60050-151:2001, 151-16-10, modified – The order of phrases has been
changed.]
3.5.2
nominal value
value of a quantity used to designate and identify a component, device, equipment, or system
Note 1 to entry: The nominal value is generally a rounded value.
Note 2 to entry: In this document, the term "nominal" is used only as common practice to designate contact line
and battery voltage circuits.
[SOURCE: IEC 60050-811:2017, 811-11-01, modified – Note 2 to entry has been added.]

– 12 – IEC 60077-1:2017 © IEC 2017
3.5.3
rated value
value of a quantity used for specification purposes, established for a specified set of operating
conditions of a component, device, equipment, or system
[SOURCE: IEC 60050-811:2017, 811-11-02]
3.5.4
equivalent continuous duty
duty of electrical equipment on rolling stock, which corresponds to the actual service,
generally characterized by values of current, voltage, compressed air pressure, etc., which
vary with time
Note 1 to entry: The various parts of the equipment are defined by a complete statement of the conditions to be
fulfilled. However, it is sometimes sufficient to specify an equivalent duty which corresponds from the point of view
of either electrical, mechanical or thermal stresses to the service considered, and is known as being equivalent to
the actual service. It is the equivalent continuous duty to which the relevant tests are referred.
3.5.5
equivalent continuous rated current
current corresponding to the equivalent continuous duty
3.6 Terms related to lifetime
3.6.1
ageing
change with passage of time of physical, chemical or electrical properties of a component or
module under specified operating conditions, which may result in degradation of significant
performance characteristics
Note 1 to entry: This entry was numbered 393-18-41 in IEC 60050-393:2003.
[SOURCE: IEC 60050-395:2014, 395-07-100]
3.6.2
endurance
ability to withstand the action of ageing factors
Note 1 to entry: The endurance may be characterized by the results of accelerated ageing tests.
[SOURCE: IEC 60050-212:2010, 212-12-08]
3.6.3
thermal endurance
ability to withstand the action of temperature
[SOURCE: IEC 60050-212:2010, 212-12-09]
3.6.4
durability
ability to perform as required, under given conditions of use and maintenance, until the end of
useful life
Note 1 to entry: For the purpose of this document, "durability" is used in order to express the expectancy of the
life duration (time or number of operating cycles) which can be performed by the equipment before repair or
replacement of parts.
[SOURCE: IEC 60050-192:2015, 192-01-21, modified – Note 1 to entry has been added.]

IEC 60077-1:2017 © IEC 2017 – 13 –
3.7 Abbreviated terms
AC Alternating Current
DC Direct Current
EMC Electromagnetic Compatibility
RMS Root Mean Square value
PD Pollution degree
OV Overvoltage category
VC Voltage Class
4 Classification
This clause is intended to list the characteristics of equipment on which information may be
given by the manufacturer and which shall be verified by testing where relevant.
Equipment covered by this document is classified, according to the supply source of its
control and auxiliary circuits. Details are given in 5.3.3.2.
5 Characteristics of the utilization category
5.1 General
The utilization category of equipment defines the intended application and shall be specified
in the relevant product standard; it is characterized by one or more of the following
parameters:
• current(s);
• voltage(s);
• frequency(ies);
• air pressure(s).
See also Annex A.
NOTE This list is not exhaustive and can include other parameters as applicable.
5.2 Rated voltages
5.2.1 General
The term rated voltage can generally be related to both the input and output values of
equipment. The quantity is assigned generally by the manufacturer.
5.2.2 Rated operational voltage (U )
r
The rated operational voltage of equipment is a value of voltage which combined with a rated
operational current and rated operational frequency, determines the application of the
equipment and to which the relevant tests and the utilization categories are referred.
NOTE Symbol U was used in the first edition of IEC 60077-1. U is used in IEC 61992-1.
e Ne
5.2.3 Rated insulation voltage (U )
Nm
Definition of a rated insulation voltage is given in IEC 62497-1.
The rated insulation voltage is the value of voltage to which rated impulse voltage and
creepage distances are referred.

– 14 – IEC 60077-1:2017 © IEC 2017
When the voltage is not purely of sinusoidal or of continuous form, the RMS or mean value
alone cannot be considered to prescribe the rated insulation voltage of the components.
In the absence of any knowledge of the influence on dielectric strength of:
• the ratio between the duration of periodic impulses and their repetition period;
• the number of impulses during each burst;
• the voltage rate of rise of the impulse (dv/dt),
it is recommended that this voltage be considered as being equal to the real RMS value, but
not less than 70 % of the peak value.
5.2.4 Power-frequency test voltage (U )
a
The power-frequency test voltage is the RMS value of power-frequency sinusoidal voltage
which does not cause an insulation failure under specified conditions of test.
U is given in IEC 62497-1.
a
5.2.5 Rated impulse voltage (U )
Ni
Definition of a rated impulse voltage is given in IEC 62497-1.
The rated impulse voltage is used for determining minimum required clearances and dielectric
test voltages.
5.3 Rated voltages for electric equipment
5.3.1 Equipment supplied by a contact line
The rated operational voltage (U ) for equipment supplied from the contact line is the highest
r
permanent voltage (U ) of the contact line voltage as defined by IEC 60850.
max1
5.3.2 Equipment supplied by a transformer
The rated operational voltage (U ) for equipment supplied from a winding of a transformer is
r
equal to the RMS voltage at the terminals of the winding when the transformer primary is
supplied at the rated operational voltage. If a second transformer is interposed between the
above-mentioned transformer and the equipment, the rated operational voltage (U ) is equal
r
to the above-mentioned rated operational voltage multiplied by the transformer ratio of the
second transformer.
5.3.3 Equipment supplied by DC low voltage sources
5.
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