IEC 62505-2:2009

IEC 62505-2 ®
Edition 1.0 2009-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Railway applications – Fixed installations – Particular requirements for a.c.
switchgear –
Part 2: Single-phase disconnectors, earthing switches and switches with U
n
above 1 kV
Applications ferroviaires – Installations fixes – Exigences particulières pour
appareillage à courant alternatif –
Partie 2: Sectionneurs monophasés, sectionneurs de terre et commutateurs
avec U supérieur à 1 kV
n
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IEC 62505-2 ®
Edition 1.0 2009-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Railway applications – Fixed installations – Particular requirements for a.c.
switchgear –
Part 2: Single-phase disconnectors, earthing switches and switches with U
n
above 1 kV
Applications ferroviaires – Installations fixes – Exigences particulières pour
appareillage à courant alternatif –
Partie 2: Sectionneurs monophasés, sectionneurs de terre et commutateurs
avec U supérieur à 1 kV
n
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
M
CODE PRIX
ICS 45.060 ISBN 978-2-88910-746-9
– 2 – 62505-2 © IEC:2009
CONTENTS
FOREWORD.3
INTRODUCTION.5
1 Scope.6
2 Normative references .6
3 Terms and definitions .6
4 Normal and special service conditions [2] .7
5 Rating [4] .7
5.1 General .7
5.2 Rated voltage (U ) .7
Ne
5.3 Nominal voltage (U ) .7
n
5.4 Rated insulation voltage (U ) [4.2] .7
Nm
5.5 Rated short-time withstand current [4.5] .8
5.6 Rated peak withstand current [4.6] .8
5.7 Rated duration of short-circuit current [4.7].8
5.8 Rated breaking current [4.101] .9
5.9 Rated no-load transformer breaking current [4.105].9
5.9.1 Rated no-load transformer breaking current for switch-disconnectors
[4.105.1] .9
5.9.2 Rated no-load transformer breaking current for general purpose
switches [4.105.2].9
5.9.3 Rated line charging breaking current [4.105.3].9
5.10 Rated short-circuit making current [4.108] .9
5.11 Co-ordination of rated values .9
6 Design and construction [5] .10
7 Type tests [6] .11
7.1 General .11
7.2 Test voltages [6.1.5].11
7.3 Mechanical operation test at ambient air temperature [6.102] .11
8 Routine tests [7] .11
Bibliography.12

Table 1 – Nominal voltages (U ), rated impulse voltages (U ) and short-duration
n Ni
power-frequency (a.c.) test levels (U ) for circuits connected to the contact line .8
a
Table 2 – Co-ordination table of rated values for devices.10

62505-2 © IEC:2009 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
RAILWAY APPLICATIONS –
FIXED INSTALLATIONS –
PARTICULAR REQUIREMENTS FOR AC SWITCHGEAR –

Part 2: Single-phase disconnectors, earthing
switches and switches with U above 1 kV
n
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 provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with an IEC Publication.
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 62505-2 has been prepared by IEC technical committee 9:
Electrical equipment and systems for railways. This standard is based on EN 50152-2.
The text of this standard is based on the following documents:
FDIS Report on voting
9/1220/FDIS 9/1233/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.

– 4 – 62505-2 © IEC:2009
A list of all parts of IEC 62505 series, under the general title Railway applications – Fixed
installations – Particular requirements for a.c. switchgear, can be found on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until
the maintenance result 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.
62505-2 © IEC:2009 – 5 –
INTRODUCTION
The IEC Standard series 62505 is divided as follows:
Part 1: Single-phase circuit breakers with U above 1 kV.
n
Part 2: Single-phase disconnectors, earthing switches and switches with U above 1 kV.
n
Part 3-1: Measurement, control and protection devices for specific use in a.c. traction
systems – Application guide.
Part 3-2: Measurement, control and protection devices for specific use in a.c. traction
systems – Single-phase current transformers.
Part 3-3: Measurement, control and protection devices for specific use in a.c. traction
systems – Single-phase inductive voltage transformers.
IEC 62505-2 has to be used in conjunction with IEC 62271-102 and IEC 60265-1.
Where a particular Clause of IEC 62271-102 and IEC 60265-1 is not mentioned in this
standard, that Clause 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 62271-102 and IEC 60265-1 is to be adapted accordingly.
The numbering of clauses in the IEC 62271 series and IEC 60265-1 is not used in this
Standard. The numbering in square brackets refers to the numbering of clauses in the
IEC 62271 series and IEC 60265-1.
NOTE 1 Where terms defined in IEC 62271-102 and IEC 60265-1 conflict with definitions of the same terms as
given in IEC 60050-811:1991, or the other railway applications documents listed in the normative references, the
definitions used in IEC 62271-102 and IEC 60265-1 are to be used.
NOTE 2 The suffix N which appears in this Standard for rated values is not used in IEC 62271-102 and
IEC 60265-1.
– 6 – 62505-2 © IEC:2009
RAILWAY APPLICATIONS –
FIXED INSTALLATIONS –
PARTICULAR REQUIREMENTS FOR AC SWITCHGEAR –

Part 2: Single-phase disconnectors, earthing
switches and switches with U above 1 kV
n
1 Scope
This part of IEC 62505 is applicable to single-phase a.c. one-pole disconnectors, earthing
switches and switches (switch-disconnectors and general purpose switches) designed for
indoor or outdoor fixed installations for operation at frequencies of 16,7 Hz, 50 Hz and 60 Hz
on traction systems having an U above 1 kV up to 52 kV.
Nm
This International Standard is also applicable to two-pole disconnectors, earthing switches
and switches (switch-disconnectors and general purpose switches) connected in the following
manner either:
– one pole supplying the connection to the contact line of the track, the other supplying the
connection to the feeder cable which runs alongside the same track and is used to boost
the track voltage at regular intervals in combination with autotransformers;
– or the two poles of the disconnector, earthing switch or switch (switch-disconnector or
general purpose switch) are connected in series to provide secure isolation (i.e. two
breaks in series).
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 60265-1:1998, High voltage switches – Part 1: Switches for rated voltages above 1 kV
and less than 52 kV
IEC 60850:2007, Railway applications – Supply voltages of traction systems
IEC 62271-1:2007, High-voltage switchgear and controlgear – Part 1: Common specifications
IEC 62271-102:2003, High-voltage switchgear and controlgear – Part 102: Alternating current
disconnectors and earthing switches
IEC 62497-1, Railway applications – Insulation co-ordination – Part 1: Basic requirements –
Clearances and creepage distances for all electrical and electronic equipment
IEC 62505-1:2009, Railway applications – Fixed installations – Particular requirements for
a.c. switchgear – Part 1: Single phase circuit breakers with U above 1 kV
n
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60265-1 and
IEC 62271-102 and the following apply:

62505-2 © IEC:2009 – 7 –
3.1
disconnecting device
general term covering circuit-breakers, disconnectors, earthing switches, switches, including
switch-disconnectors and general purpose switches
3.2
single-pole disconnecting device
disconnecting device with one electrically separated conducting path for the main circuit
suitable for use in a single phase circuit
NOTE The construction arrangement of this device is in principle identical to one phase of a three-phase
disconnecting device.
3.3
two-pole disconnecting device
disconnecting device with two independent electrically separated conducting paths for the
main circuit.
NOTE 1 The two paths may be connected in series for use in a single phase circuit where the establishment of
the two paths is simultaneous. The construction arrangement of this device is in principle identical to two phases of
a three phase disconnecting device.
NOTE 2 This device is intended to be suitable to interrupt or establish simultaneously a single phase circuit in two
different points.
4 Normal and special service conditions [2]
Clause 2 of IEC 62271-102 and IEC 60265-1 is applicable except as follows:
Addition:
The equipment covered by this standard shall be suitable for installation in trackside locations
subject to vibrations from passing trains, airborne iron dust contamination from train brakes
and shall meet the electromagnetic compatibility (EMC) requirements.
For special service conditions, agreement is necessary between purchaser and supplier.
5 Rating [4]
5.1 General
Clause 4 of IEC 62271-102 and IEC 60265-1 is applicable except as follows:
5.2 Rated voltage (U )
Ne
The rated voltage U shall be chosen taking into consideration the maximum voltage level
Ne
suitable to be permanently applied to the disconnecting device (i.e. highest permanent voltage
U as defined in IEC 60850).
max1
5.3 Nominal voltage (U )
n
The nominal voltage U shall be one of the voltages listed in Table 1 of IEC 60850.
n
5.4 Rated insulation voltage (U ) [4.2]
Nm
The values of the rated insulation voltage U , of the rated impulse withstand voltage U and
Nm Ni
of the power-frequency withstand voltage U shall be as given in Table 1, taken from the
a
values listed in IEC 62497-1.
– 8 – 62505-2 © IEC:2009
Table 1 – Nominal voltages (U ), rated impulse voltages (U ) and short-duration power-
n Ni
frequency (a.c.) test levels (U ) for circuits connected to the contact line
a
a
b, c
U OV U
U U U
a
n Nm Ni
(1,2/50 μs)
A B A B
kV kV kV kV kV kV kV
IEC 60850 IEC 62497-1 (IEC 62271-1) IEC 62497-1
(24,0) 3 95 110 38 or 50 50 or 60
4 125 145 50 60
17,5
d
(36,0) 3 145 165 70 80
d
4 170 195 70 or 95 95 or 110
not
20 24
applicable
4 150 175 50 60
b
3 170 200 70 or 95 95 or 110
not
applicable
b b b
27,5 4 200 220 95 110
b b
(52,0) 3 200 220 95 110
d
4 250 290 95 110
not
applicable
4 200 230 70 80
d
see 52,0 (72,5) 3 250 290 95 110
Note 3
4 300 375 140 160
NOTE 1 The choice of the different values of U given for the same U , depends upon the highest non permanent
Ni n
voltages (such as U of IEC 60850) actually appearing in the system.
max2
NOTE 2 OV3 and OV4 are overvoltage levels depending on the system configuration and degree of overvoltage
control (inherent control or protective control) as given in IEC 62497-1.
NOTE 3 Take care that in those cases in which for circuit reasons it may happen that a higher voltage is applied to the
disconnecting device terminals in transient conditions, a higher rated insulation voltage between contacts might be

necessary (e.g. U = 52 kV for U = 25 kV).
Nm n
a
The values in brackets give the rated voltages according to Table 1a of IEC 62271-1 having the nearest equivalence
in test withstand voltages with the values for single-phase equipment given in this Table.
b
These values are used in railway application only and are not of wide industrial use.
c
Alternative values are left to purchaser choice or by agreement.
d
Values derived from IEC 62271-1.
A To earth and between poles.
B Across the isolating distance (not applicable to earthing switches).

5.5 Rated short-time withstand current [4.5]
Subclause 4.5 of IEC 62271-102 and 4.5 of IEC 60265-1 are applicable.
5.6 Rated peak withstand current [4.6]
Subclause 4.6 of IEC 62271-102 and 4.6 of IEC 60265-1 are applicable.
5.7 Rated duration of short-circuit current [4.7]
Subclause 4.7 of IEC 62271-102 and 4.7 of IEC 60265-1 are applicable.

62505-2 © IEC:2009 – 9 –
This does not apply to disconnectors, but is applicable to earthing switches operating as
make-proof earthing switches.
5.8 Rated breaking current [4.101]
Subclause 4.101 of IEC 60265-1 is applicable for general purpose switches.
In addition, when specified by the purchaser, a disconnecting device may be specified
capable of switching the capacitive current of the feeder cable or the catenary at a voltage
value not less than U (see IEC 60850), and with a current not exceeding 10 A. Moreover
max1
switches, when required to do so, shall be suitable to disconnect a capacitor bank. The
resulting breaking current shall be tested in accordance with the requirements of IEC 62505-1
at the power factor and test requirements agreed between purchaser and supplier.
TRV values and out-of-phase breaking current are not applicable to disconnecting devices
covered by this standard.
5.9 Rated no-load transformer breaking current [4.105]
5.9.1 Rated no-load transformer breaking current for switch-disconnectors [4.105.1]
When specified by the purchaser a switch-disconnector may be required to break the no-load
current of a transformer. The no-load current and the cos φ of the transformer shall be
specified by the purchaser.
The test procedure is subject to agreement between purchaser and supplier.
5.9.2 Rated no-load transformer breaking current for general purpose switches
[4.105.2]
The no-load requirements or the current and cos φ of the transformer are to be given by the
purchaser.
The test procedure is subject to agreement between purchaser and supplier.
5.9.3 Rated line charging breaking current [4.105.3]
When specified by the purchaser the unit shall be capable of switching the capacitive current
of the feeder cable or the catenary at a voltage value of not less than U (see IEC 60850)
max1
and with a current not exceeding 10 A.
5.10 Rated short-circuit making current [4.108]
Subclause 4.101 of IEC 62271-102 and 4.108 of IEC 60265-1 are applicable.
This does not apply to disconnectors.
5.11 Co-ordination of rated values
Co-ordinated values of rated voltages, short-circuit breaking currents (if any) and rated
normal currents are given in Table 2.

– 10 – 62505-2 © IEC:2009
Table 2 – Co-ordination table of rated values for devices
Basic voltages Rated withstand Rated current
current
Short Peak
time
r.m.s.
a
U
U U I
n Nm n
kV kV kV kA kA A
b b
15 17,5 (24) 8 20 400 630 1 250
12,5 32 630 1 250
16 40 630 1 250 1 600
20 50 630 1 250 1 600
2 500
25 63 1 250 1 600 2 000
31,5 80 1 250 1 600 2 000
40 100 1 600 2 000 2 500 4 000
50 1 600 2 000 2 500 4 000
15 24,0 (36) 8 20 630
b b
25 27,5 12,5 32 630 1 250
16 40 630 1 250 1 600 2 000 2 500
20 50 630 1 250 1 600 2 000 2 500
25 63 1 250 1 600 2 000 2 500
31,5 80 1 250 1 600 2 000 2 500 4 000
40 100 1 250 1 600 2 000 2 500 4 000
50 1 600 2 500 4 000
20 24,0 N/A 12,5 32 600 1 200
20 50 600 1 200
25 63 600 1 200 2 000 3 000
40 100 1 200 2 000 3 000
50 125 1 200  4 000
63 158 2 000 3 000 4 000
25 30,0 N/A 12,5 32 600 1 200
16 40 600 1 200
25 63 600 1 200 2 000
31,5 80 1 200 2 000 3 000
40 100 1 200 2 000 3 000
25 36,0 (52) 8 20  800 1 250
12,5 32 1 250
20 50 630 1 250 1 600 2 000 2 500
31,5 80 1 250 1 600 2 000
52,0 (72,5) 12,5 32  800 1 250
16 40 800 1 250
20 50 1 250 1 600 2 000 2 500
31,5 80 1 250 1 600 2 000 2 500
50 1 600 2 500 4 000
a
The values in brackets give the rated voltages according to Table 1a of IEC 62271-1 having the nearest equivalence
in test withstand voltages with the values for single-phase equipment given in this Table.
b
These values are used in railway applications only and are not of wide industrial use.

NOTE Table 2 is intended to be used as a guide and gives preferred values.
6 Design and construction [5]
Clause 5 of IEC 62271-102 and IEC 60265-1 is applicable, except as follows:
For switches with a breaking medium like gas, the effective pressure of this gas at 20 °C shall
not exceed 6 × 10 Pa (added on the atmospheric pressure of 10 Pa).

62505-2 © IEC:2009 – 11 –
7 Type tests [6]
7.1 General
Clause 6 of IEC 62271-102 and IEC 60265-1 is applicable except as follows.
7.2 Test voltages [6.1.5]
Test voltage levels given in Table 1 and the requirements given in IEC 62497-1 are
applicable. Subclause 6.2.6 of IEC 62271-1 is otherwise applicable.
7.3 Mechanical operation test at ambient air temperature [6.102]
The mechanical operation test shall be made at the ambient air temperature of the test
location. The ambient air temperature should be recorded in the test report. Auxiliary
equipment forming part of the operating devices shall be included in the test.
The mechanical operation test shall consist of the following operating cycles:
Class 1: general purpose switches: 1 000 cycles;
Class 2: high density use switching devices:
for earthing switches: 1 000 cycles;
for disconnectors: 3 000 cycles;
for switches: 10 000 cycles.
Where switches are operated at every train passing, higher values may be agreed between
purchaser and supplier
The test shall be made without voltage on, or current in the main circuit.
During the test, lubrication, mechanical adjustment or other kind of maintenance are not
allowed.
Subclause 6.102.2 of IEC 62271-102 is applicable for disconnectors and earthing switches.
8 Routine tests [7]
Clause 7 of IEC 62271-102 and IEC 60265-1 is applicable except as follows:
For dielectric tests the values given in Table 1 and IEC 62497-1 apply.

– 12 – 62505-2 © IEC:2009
Bibliography
IEC 60044-1:1996, Instrument transformers – Part 1: Current transformers
IEC 60050-151, International Electrotechnical Vocabulary (IEV) – Chapter 151: Electrical and
magnetic devices
IEC 60050-441, International Electrotechnical Vocabulary (IEV) – Chapter 441: Switchgear,
controlgear and fuses
IEC 60050-446, International Electrotechnical Vocabulary (IEV) – Chapter 446: Electrical
relays
IEC 60050-604, International Electrotechnical Vocabulary (IEV) – Chapter 604: Generation,
transmission and distribution of electricity – Operation
IEC 60050-605, International Electrotechnical Vocabulary (IEV) – Chapter 605: Generation,
transmission and distribution of electricity - Substations
IEC 60060-1:1989, High-voltage test techniques – Part 1: General definitions and test
requirements
IEC 60085, Electrical insulation – Thermal evaluation and designation
IEC 60137, Insulated bushings for alternating voltages above 1 kV
IEC 60270, High-voltage test techniques – Partial discharge measurements
IEC 60296, Fluids for electrotechnical applications – Unused mineral insulating oils for
transformers and switchgear
IEC 60376, Specifi
...