IEC 62505-3-3:2020

IEC 62505-3-3 ®
Edition 2.0 2020-01
INTERNATIONAL
STANDARD
Railway applications – Fixed installations – Particular requirements for AC
switchgear –
Part 3-3: Measurement, control and protection devices for specific use in AC
traction systems – Voltage transformers

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IEC 62505-3-3 ®
Edition 2.0 2020-01
INTERNATIONAL
STANDARD
Railway applications – Fixed installations – Particular requirements for AC

switchgear –
Part 3-3: Measurement, control and protection devices for specific use in AC

traction systems – Voltage transformers

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 45.060.01 ISBN 978-2-8322-7668-6

– 2 – IEC 62505-3-3:2020 © IEC 2020
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Terms, definitions and abbreviated terms . 7
3.1 Terms and definitions . 7
3.2 Abbreviated terms . 8
4 Service conditions . 8
5 Rating. 8
5.1 General . 8
5.2 Nominal voltage (U ) . 8
n
5.3 Rated voltage (U ) . 8
Ne
5.4 Insulation coordination . 9
5.4.1 General . 9
5.4.2 Rated insulation level . 9
5.5 Rated frequency . 10
5.6 Rated output . 10
5.7 Rated accuracy class . 10
5.8 Standard values of rated voltages . 10
5.9 Standard values of rated voltage factor . 10
5.10 Ferroresonance . 11
6 Design and construction . 11
6.1 General . 11
6.2 Transformer construction . 11
6.3 Requirements for the external insulation . 11
6.4 Nameplates. 12
7 Tests . 12
7.1 General . 12
7.2 Ferroresonance withstand test . 12
7.3 Partial discharge test . 12
8 Rules for transport, storage, erection, operation and maintenance . 13
9 Safety . 13
10 Influence of the product on the environment . 13
11 Information to be given with enquiries, tenders and orders . 13
Bibliography . 14

Table 1 – Nominal voltages (U ), rated voltages (U ), rated impulse voltages (U )
n Ne Ni
and power-frequency withstand voltage (U ) for circuits connected to the contact line . 9
d
Table 2 – Partial discharge test voltages and permissible levels . 13

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
RAILWAY APPLICATIONS – FIXED INSTALLATIONS –
PARTICULAR REQUIREMENTS FOR AC SWITCHGEAR –

Part 3-3: Measurement, control and protection devices
for specific use in AC traction systems – Voltage transformers

FOREWORD
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all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
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International Standard IEC 62505-3-3 has been prepared by IEC technical committee 9:
Electrical equipment and systems for railways.
This second edition cancels and replaces the first edition published in 2009. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
– This standard was revised to reflect the latest versions of standards referenced and to
remove text already included in the IEC 61869 series.
– The structure of the document was adapted to that of IEC 62505‑1 and IEC 62505‑2.
– Ratings have been added to provide designations in line with other railway standards, for
example IEC 62497.
– 4 – IEC 62505-3-3:2020 © IEC 2020
– Tests requirements have been detailed to meet operating conditions of railway
applications.
– Partial discharge voltages have been specified in Table 2.
The text of this International Standard is based on the following documents:
FDIS Report on voting
9/2556/FDIS 9/2562/RVD
Full information on the voting for the approval of this International Standard can be found in
the report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
This document has to be read in conjunction with IEC 61869‑1:2007 and IEC 61869‑3:2011
(see Introduction).
A list of all parts in the IEC 62505 series, published under the general title Railway
applications – Fixed installations – Particular requirements for AC switchgear, can be found
on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
A bilingual version of this publication may be issued at a later date.

INTRODUCTION
Where a particular clause/subclause of IEC 61869‑3 is not mentioned in this standard, that
clause/subclause applies as far as reasonable. Where requirements relate exclusively to
three-phase systems or to voltages outside those in use in traction systems, they are not
applicable. Where this standard states "addition" or "replacement", the relevant text of
IEC 61869‑3 is to be adapted accordingly.
The numbering of clauses in the IEC 61869 series is similar to that in the IEC 62505 series.
Where terms defined in IEC 61869‑1 and IEC 61869‑3 conflict with definitions of the same
terms as given in IEC 60050‑811:2017 or of the other railway applications documents listed in
the normative references, the definitions in IEC 61869‑1 and IEC 61869‑3 are to be used.
NOTE The suffix N which appears in this standard for rated values is not present in IEC 61869‑1 and
IEC 61869‑3.
References in subclauses of IEC 61869‑1 and IEC 61
...