IEC 60850:2014

IEC 60850 ®
Edition 4.0 2014-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Railway applications – Supply voltages of traction systems

Applications ferroviaires – Tensions d'alimentation des réseaux de traction

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IEC 60850 ®
Edition 4.0 2014-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Railway applications – Supply voltages of traction systems

Applications ferroviaires – Tensions d'alimentation des réseaux de traction

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX R
ICS 45.060 ISBN 978-2-8322-1928-7

– 2 – IEC 60850:2014  IEC 2014
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Voltages and frequencies of traction systems . 8
4.1 Voltages . 8
4.2 Frequency . 10
5 Testing . 11
6 Test methodology . 11
6.1 Measurement of the voltage on the line . 11
6.1.1 Rolling stock . 11
6.1.2 Fixed installations (see Table 3) . 11
6.2 Measurement of the frequency on the line (see Table 4) . 12
Annex A (normative) Maximum value of voltage U according to duration (see Figure A.1) . 13
Annex B (normative) Alternative values of traction power supply systems . 15
Annex C (informative) Changes, interruptions and distortion of voltages . 17
C.1 Rapid voltage changes . 17
C.2 Contact line voltage dips . 17
C.3 Short interruptions of the voltage . 17
C.4 Long interruptions of the voltage . 17
C.5 Distortion of the voltage (AC and DC) . 17
C.6 Testing . 18
C.6.1 General . 18
C.6.2 Rolling stock . 18
C.6.3 Fixed Installations . 18
Bibliography . 19

Figure A.1 – Maximum value of voltage U according to duration . 13

Table 1 – Nominal voltages and their permissible limits in values and duration . 9
Table 2 – Tests . 11
Table 3 – Measurement of the voltage on the line . 11
Table 4 – Measurement of the frequency on the line . 12
Table A.1 – Overvoltages . 14
Table B.1 – Implemented voltages in the world and their permissible limits in values
and duration . 15
Table C.1 – Measurement of the voltage variations and interruptions . 18

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
RAILWAY APPLICATIONS –
SUPPLY VOLTAGES OF TRACTION SYSTEMS

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
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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 60850 has been prepared by IEC technical committee 9: Electrical
equipment and systems for railways.
The text of this standard is based on the European Norm EN 50163 (2004).
This fourth edition cancels and replaces the third edition of IEC 60850 published in 2007. This
edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
– clarification of some definitions in Clause 3,
– Subclause 4.1 completed,
– Table 1 modified,
– Annex B modified with new Table B.1.

– 4 – IEC 60850:2014  IEC 2014
The text of this standard is based on the following documents:
FDIS Report on voting
9/1978/FDIS 9/1996/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
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.
RAILWAY APPLICATIONS –
SUPPLY VOLTAGES OF TRACTION SYSTEMS

1 Scope
This International Standard specifies the main characteristics of the supply voltages of
traction systems, such as traction fixed installations, including auxiliary devices fed by the
contact line, and rolling stock, for use in the following applications:
– railways;
– guided mass transport systems such as tramways, light trains, elevated and underground
railways and trolleybus systems;
– rail bound material transportation systems, e.g for coal or iron-ore.
This standard is also applicable for low speed maglev trains or linear motor transport
systems.
This standard does not apply to:
– mine traction systems in underground mines;
– cranes, transportable platforms and similar transportation equipment on rails, temporary
structures (e.g. exhibition structures) insofar as these are not supplied directly or via
transformers from the contact line system and are not endangered by the traction power
supply system;
– suspended cable cars;
– funicular railways.
This standard deals with long term overvoltages as shown in Annex A.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and
are indispensable for its application. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 61133:2006, Railway applications – Rolling stock – Testing of rolling stock on completion
of construction and before entry into service
IEC 62128-1:2013, Railway applications – Fixed installations – Electrical safety, earthing and
the return circuit – Part 1: Protective provisions against electric shock
IEC 62497-2, Railway applications – Insulation coordination – Part 2: Overvoltages and
related protection
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 62128-1, as well as
the following apply.
—————————
A new edition is under development.

– 6 – IEC 60850:2014  IEC 2014
NOTE See bibliography and its reference to EN 50160 for clarification of some definitions.
3.1
electric traction system
railway electrical distribution network used to provide energy for rolling stock
Note 1 to entry: The system includes:
– contact line systems,
– return circuit of electric traction systems,
– running rails of non-electric traction systems, which are in the vicinity of, and conductively connected to the
running rails of an electric traction system,
– electrical installations, which are supplied from contact lines either directly or via a transformer,
– electrical installations in substations, which are utilized solely for distribution of power directly to the contact
line,
– electrical installations of switching stations.
[SOURCE: IEC 62128-1:2013, 3.4.1]
3.2
voltage
U
potential at the train’s current collector or elsewhere on the contact line, measured between
the contact line and the return circuit
Note 1 to entry: The values considered in this standard are the mean value of DC voltage or the r.m.s. value of
the fundamental AC voltage.
3.3
nominal voltage
U
n
designated value for a system
3.4
highest permanent voltage
U
max1
maximum value of the voltage likely to be present indefinitely
3.5
highest non-permanent voltage
U
max2
maximum value of the voltage likely to be present for a limited period of time
3.6
overvoltage
any voltage having a peak value exceeding the corresponding peak value of maximum
steady-state voltage at normal operating conditions
3.7
long-term overvoltage
overvoltage higher than U lasting typically more than 20 ms, due to low impedance
max2
phenomena, for example a rise in substation primary voltage
Note 1 to entry: Such overvoltages are independent of line load and may be described by a voltage-time curve
only. See Annex A for information on this curve.

3.8
highest long term overvoltage
U
max3
voltage defined as the highest value of the long-term overvoltage for t = 20 ms. This value is
independent from frequency
3.9
lowest permanent voltage
U
min1
minimum value of the voltage likely to be present indefinitely
3.10
lowest non-permanent voltage
U
min2
minimum value of the voltage likely to be present for a limited period of time
3.11
voltage variation
increase or decrease of voltage normally due to variation of the total load of a distribution
system or a part of it
3.12
rapid voltage change
single rapid variation of the r.m.s. value of a voltage between two consecutive levels which
are sustained for definite but unspecified durations
3.13
supply voltage dip
sudden reduction of the supply voltage to a value of less than U , followed by a voltage
min2
recovery after a short period of time
Note 1 to entry: Conventionally, the duration of a voltage dip is between 10 ms and 1 min. The depth of a voltage
dip is defined as the difference between the minimum r.m.s. voltage during the voltage dip and the nominal voltage
U . Voltage changes which do not reduce the supply voltage to less than U are not considered to be dips.
n min2
3.14
supply interruption
condition in which the voltage at the supply-terminals is lower than 1 % of the nominal voltage
U
n
Note 1 to entry: A supply interruption can be classified as:
– pre-arranged, when consumers are informed in advance, to allow the execution of scheduled works on the
distribution systems, or
– accidental, caused by permanent or transient faults, mostly related to external events, equipment failures or
interference. An accidental interruption is classified as:
• a long interruption (longer than 3 min) caused by a permanent fault,
• a short interruption (up to 3 min) caused by a transient fault .
3.15
contact line
conductor system for supplying traction units with electrical energy via current-collection
equipment
Note 1 to entry: This includes all current-collecting conductors and conducting rails or bars, including the
following:
– reinforcing feeders;
– cross-track feeders;
– 8 – IEC 60850:2014  IEC 2014
– disconnectors;
– section insulators;
– over-voltage protection devices;
– supports that are not insulated from the conductors;
– insulators connected to live parts;
but excluding other conductors, such as the following:
– along-track feeders;
– earth wires and return conductors.
[SOURCE: IEC 60913:2013, 3.1.2]
3.16
substation
traction substation
installation, the main function of which is to supply a contact line system, at which the voltage
of a primary supply system, and in certain cases the frequency, is converted to the voltage
and frequency of the contact line
3.17
normal operating conditions
traffic operating to the design timetable and train formation used for power supply fixed
installation design. Power supply equipment is operated according to standard rules.
Note 1 to entry: Standard rules may vary depending on the infrastructure manager’s policy.
3.18
abnormal operating conditions
either higher traffic loads or outage of power supply equipment outside the standard rules
Note 1 to entry: Under these conditions, traffic may not operate to the design timetable.
4 Voltages and frequencies of traction systems
4.1 Voltages
The characteristics of the generic voltages of traction power supply systems (overvoltages
excluded) are specified in Table 1 below.
“Generic”, means that these voltages of the traction power supply systems are to be used in
projects which have common/classical operating parameters and allow the use of other
generic international standards. These traction power supply systems are implemented in
many countries over the world and their efficiency is proven.
However, some countries have studied and implemented variations of the values based from
these generic voltages of traction power supply systems, They have been made to solve
difficulties or particular conditions such as very heavy power demand. These conditions may
be:
• Need of high amount of energy avoiding voltage drops in the rails / contact line loop.
• Lack of insulation distance (narrow gauge under bridges or tunnels).
• Difficulties to find the appropriate power supply connection to the grid.
• Long tunnel necessitating very long distance between substations.

• Particular RAMS (Reliability, Avaibility, Maintainability, Safety) requirement (e.g.
extended supply zone).
• Any other particular local condition.
These alternatives are presented in Annex B, Table B.1. It is suggested, during engineering
studies to read this Annex B in order to consider it.
The choice of using these alternatives shall be made taking into account interoperability
requirements if connection with another railway system is foreseen.
Table 1 – Nominal voltages and their permissible limits in values and duration
Electrification Lowest non- Lowest Nominal Highest Highest non-
system permanent permanent voltage permanent permanent
voltage voltage voltage voltage
U U U U U
min2 min1 n max1 max2
V V V V V
500 750 900 1 000
DC (mean values) 1 000 1 000 1 500 1 800 1 950
2 000 2 000 3 000 3 600 3 900
a
11 000 12 000 15 000 17 250 18 000
b
19 000 25 000 27 500 29 000
AC (r.m.s. values) 17 500
a
16,7 Hz.
b
50 Hz and 60 Hz.
The following requirements shall be fulfilled:
a) the duration of voltages between U and U shall not exceed 2 min;
min1 min2
the duration of voltages between U and U shall not exceed 5 min;
max1 max2
b) the voltage of the busbar at the substation at no load condition shall be less than or equal
to U . For DC substations, it is acceptable to have this voltage at no load condition less
max1
than or equal to U , provided that when a train is present, the voltage at this train’s
max2
pantograph (s) is in accordance with Table 1 and its requirements;
≤ U ≤ U ;
c) under normal operating conditions, voltages shall lie within the range U
min1 max2
d) under abnormal operating conditions the voltages in the range U ≤ U ≤ U in
min2 min1
Table 1 shall not cause any damages or failures;
NOTE The use of train power limitation devices on board may limit the presence of low voltage on the
contact line (see IEC 62313).
e) if voltages between U and U are reached, they shall be followed by a level below
max1 max2
or equal to U , for an unspecified period;
max1
and U shall only be reached for non-permanent conditions
f) Voltages between U
max1 max2
such as
• regenerative braking,
• move of voltage regulation systems such as mechanical tap changer;
g) lowest operational voltage: under abnormal operating conditions U is the lowest limit
min2
of the contact line voltage for which the rolling stock is intended to operate.
Recommended set values for undervoltage tripping relays in fixed installations or on board
rolling stock are from 85 % to 95 % of U .
min2
– 10 – IEC 60850:2014  IEC 2014
4.2 Frequency
The frequency of the 50 Hz and 60 Hz electric traction systems is imposed by the three phase
grid.
NOTE 1 Therefore, the values stated in EN 50160 are applicable in Europe.
The frequency of the 16,7 Hz electric traction system (except for synchronous-synchronous
converters) is not imposed by the three phase grid.
NOTE 2 Concerning the 16,7 Hz electric traction system, strictly considered, the frequency corresponds to
16⅔ Hz. In order to simplify the denomination of the system, it is agreed to state the frequency as 16,7 Hz. This
denomination is used in this standard.
The frequencies on AC railway power systems and their permissible limits are shown
hereinafter.
Under normal operating conditions, the mean value of the fundamental frequency measured
over 10 s shall be within a range of the HV supply network.
• For systems with synchronous connection to an interconnected system:
50 Hz ± 1 % (i.e. 49,5 Hz to 50,5 Hz) for 99,5 % of a year
50 Hz + 4 %/–6 % (i.e. 47 Hz to 52 Hz) for 100 % of the time
• For systems with no synchronous connection to an interconnected system (e.g. supply
systems on certain islands):
50 Hz ± 2 % (i.e. 49 Hz to 51 Hz) for 95 % of a week
50 Hz ± 15 % (i.e. 42,5 Hz to 57,5 Hz) for 100 % of the time
For 60 Hz electric traction systems, the limit values for frequency variations are from 59 Hz to
61 Hz.
NOTE 3 Special national conditions for China, see Annex B.
For 16,7 Hz electric traction systems, the value are:
• for systems with synchronous connection to an interconnected system:
16,7 Hz ± 1 % (i.e. 16,5 Hz to 16,83 Hz) for 99,5 % of a year
16,7 Hz + 4 %/–6 % (i.e. 15,67 Hz to 17,33 Hz) for 100 % of the time
• for systems with no synchronous connection to an interconnected system (e.g. supply
systems on certain islands):
16,7 Hz ± 2 % (i.e. 16,33 Hz to 17 Hz) during 95 % of a week
16,7 Hz ± 15 % (i.e. 14,16 Hz to 19,16 Hz) during 100 % of the time
• For systems connected to the railway 16,7 Hz interconnected grid:
16,7 Hz + 2 %/–3 % (i.e. 16,17 Hz to 17 Hz) during 100 % of the time
NOTE 4 In practice, the variation of frequency is more closely controlled in some countries and regions such as in
Europe and in Japan than stated above. Vehicles will operate only within the frequency tolerances for
15 000 V/16,7 Hz from 16,17 Hz to 17 Hz and for 25 000 V/50 Hz range from 49 Hz to 51 Hz. If the frequency is out
of this range, the vehicles performance may be reduced or the vehicle drives may be disconnected.
The effects of the frequency variations may be examined by the railway operators to ensure
the absence of harmful consequences on the train signalling.
For other traction frequencies, national regulations apply.

5 Testing
The tests specified in Table 2 are applicable, depending on the type of the line and on the
need.
Table 2 – Tests
Title Technical requirement Test methodology Kind of test
6.1.1 Rolling stock Measurement
Voltage on the line 4.1
6.1.2 Fixed installations Measurement
a
Frequency 4.2 6.2 16,7 Hz only Continuous monitoring test
a
The test is only necessary for 16,7 Hz systems which are not fed by at least one synchronous–synchronous
rotating converter (= synchronous connection to an interconnected system).

NOTE Annex C describes the tests related to voltage changes.
6 Test methodology
6.1 Measurement of the voltage on the line
6.1.1 Rolling stock
Rolling stock shall be tested as described in Clause 9 of IEC 61133:2006.
6.1.2 Fixed installations (see Table 3)
Table 3 – Measurement of the voltage on the line
Where When How Acceptance condition
Substation At commissioning • Voltage recorder for the See 4.1 item c)
fundamental frequency or
Busbar, line circuit
breakers open, • Digital data loggers with a
normal operating frequency range greater than or
conditions. For DC equal to 2 kHz averaging over
substations, it may 1 s
be necessary to
• Measurement period 1 min
add a small
resistive load.
If a voltage At commissioning
No load ⇒ see substation No load ⇒ see substation
conditioning device and operating
When in operation ⇒ see ad hoc When in operation ⇒ see ad hoc
is installed along
measurement measurement
the line
Measure on either
side of the device
under no load and
normal operating
condition
Ad hoc In response to • Voltage recorder devices for the • All voltage values are greater
measurement at the problems fundamental frequency or than or equal to U .
min2
site, where
• Digital data loggers with a • All durations of voltages below
problems are
frequency range greater than or U are less than or equal to the
situated. min1
equal to 2 kHz averaging over duration stated in 4.1 item a).
1 s
• Average value of the voltage is
• Measurement period minimum between U and U .
min1 max1
1 h maximum 1 week
• All durations of voltages above
U are less than or equal to
max1
the duration stated in 4.1, item b).
• ll voltage values are less
than or equal to U .
max2
– 12 – IEC 60850:2014  IEC 2014
6.2 Measurement of the frequency on the line (see Table 4)
Table 4 – Measurement of the frequency on the line
Where When How Acceptance condition
Continuous monitoring
Only for networks, that are At commissioning and Digital data loggers with a All frequency values are in
not imposed by the 3-phase operating the ranges given in 4.2.
frequency range ≥ 2 kHz
grid
Continuous monitoring in
connection with the
frequency closed loop
control in the generating
stations or in the network
control centre
Annex A
(normative)
Maximum value of voltage U according to duration (see Figure A.1)

Voltage U
U
max3
U
max2
U
max1
Duration  t (log scale)
20 ms 1 s 5 min
Zone C Zone D Zone E
IEC
Key
Zones A and B are not shown in this Figure, see IEC 62497-2.
Zone C Long-term overvoltages
The variation of the ratio U/U versus duration is identified by
max2
–k
U = U × t
max2
where
t is the time in seconds (0,02 s ≤ t ≤ 1 s);
k is the coefficient given in Table A.1.
The representation in log coordinates of this equation is a line. The slope is given by k.
Zone D Highest non-permanent voltage U
max2
Zone E Highest permanent voltage U
max1
Figure A.1 – Maximum value of voltage U according to duration
, U and U while the values between U and
Table A.1 gives values for k, U
max1 max2 max3 max2
U are calculated using the formula given herein above.
max3
– 14 – IEC 60850:2014  IEC 2014
Table A.1 – Overvoltages
Nominal voltage U
n
750 1 500 3 000 15 000 25 000
V
Coefficient k 0,061 1 0,067 6 0,067 3 0,076 7 0,074 1
U
900 1 800 3 600 17 250 27 500
max1
U 1 000 1 950 3 900 18 000 29 000

max2
U 1 270 2 540 5 075 24 300 38 750

max3
NOTE For DC systems, concerning U limit and related time limit of 20 ms, it is known that switching-off
max3
transients of on board circuit breakers may cause these limits to be exceeded. From experience and measurement,
values up to 4 × U lasting for up to 100 ms have been recorded. These values may affect mainly on board
n
equipment such as input circuits of converters.Traction equipment cannot be protected against such peak
overvoltages This statement is for information only and is not to be tested.

Annex B
(normative)
Alternative values of traction power supply systems

Subclause 4.1: In some countries, voltages of the traction power supply systems quoted in
Table 1 are used with other tolerances or are modified or other traction power supply systems
are used. Table B.1 below describes these alternative traction power supply systems and the
location of their use.
Table B.1 – Implemented voltages in the world and
their permissible limits in values and duration
Electri- Lowest non- Lowest Nominal Highest Highest non- Country
fication permanent permanent voltage permanent permanent
system voltage voltage voltage voltage
U U U U U
min2 min1 n max1 max2
V V V V V
a
400 400 600 720 800 Existing systems
360 360 600 720 800 Japan
d g
400 500 750 900 1 000 UK
DC
(mean values)
450 450 750 900 1 000 Japan
900 900 1 500 1 800 1 950 Japan
2 000 2 000 3 000 3 600 3 800 Belgium
b
8 400 9 600 12 000 13 200 14 400 USA
c
8 750 10 000 12 500 13 750 15 000 USA
h
16 000 16 000 20 000 22 000 24 000 Japan
i
20 000 22 500 25 000 30 000 32 000 Japan
d,f
AC 12 500 /   g
19 000 25 000 27 500 29 000 UK
d,e
(r.m.s. values) 14 000
17 500 20 000 25 000 27 500 30 000 USA
17 500 19 000 25 000 27 500 30 500 China
17 500 19 000 25 000 27 500 29 000 EU
35 000 40 000 50 000 55 000 60 000 USA and RSA
a
Future DC traction systems for tramways and local railways should conform with system nominal voltage of
750 V, 1 500 V or 3 000 V.
b
25 Hz, see Table 2 of IEEE Std 16.
c
60 Hz, see Table 2 of IEEE Std 16.
d
For existing networks, which are not compliant with this standard, the values of lowest non-permanent voltage
U , for normal traffic loads but where there are power supply equipment outages outside design standards,
min2
shall be as follows:
e
Minimum voltage at which a train shall continue to operate for up to 10 min without being damaged;
f
Minimum voltage at which a train shall continue to operate for up to 2 min without being damaged.
g
For existing networks where there is no provision for voltage regulation systems, U may be exceeded.
max1
h
May be used on lines, where topographical constraints makes it difficult to use 25 000 V power supply system,
e.g. reduced gauge.
i
May be used on lines, where topographical constraints such as mountainous area and/or undersea tunnels make
the distance between substations longer, and of higher traffic density.
If use of a 25 000 V alternative is foreseen, then, it has to be noted that the infrastructure and
the rolling stock adapted to other standards for 25 000 V is not directly applicable.

– 16 – IEC 60850:2014  IEC 2014
Subclause 4.2: China
The tolerance of 50 Hz shall be ±0,2 Hz, and when the system capacity is lower, the tolerance
can be ±0,5 Hz instead of the values given in 4.2 for 50 Hz electric traction system.

Annex C
(informative)
Changes, interruptions and distortion of voltages

C.1 Rapid voltage changes
Rapid voltage changes within the ranges set up in Table 1 are an inherent part of railway
electrification due to changes in traction load, configuration of traction power supply network
or configuration of the public or railway power supply network.
C.2 Contact line voltage dips
Voltage dips are caused by faults on the contact line or on public distribution systems.
The majority of voltage dips have a duration of less than 1 s and a depth of less than 50 % of
U .
n
C.3 Short interruptions of the voltage
Under normal operating conditions, voltage short interruptions are generally caused by circuit
breakers tripping and auto-reclosing operations after the detection of faults. The auto-
reclosing cycles are described in switchgear standards (IEC 61992, IEC 62505).
Information is also given in IEC 62313.
The annual occurrence of short interruptions of the supply voltage ranges from up to a few
tens to up to several hundreds. The duration of approximately 70 % of the short interruptions
may be less than 10 s.
C.4 Long interruptions of the voltage
Accidental interruptions are usually caused by external events or actions which cannot be
prevented by the infrastructure manager.
It is not possible to indicate typical values for duration of long interruptions.
Under normal operating conditions the annual frequency of voltage interruptions longer than
3 min may be less than some units.
Indicative values are not given for prearranged interruptions, because they are announced in
advance.
C.5 Distortion of the voltage (AC and DC)
The voltage is distorted by traction and auxiliary loads, converter substations and the public
distribution system.
This results in high and low frequency harmonics which may include, only for AC, offset
(transient) and extra zero crossings.

– 18 – IEC 60850:2014  IEC 2014
C.6 Testing
C.6.1 General
The parameters for voltage changes are set out in Clauses C.1, C.2, C.3 and C.4 (technical).
Testing and acceptance requirements are detailed below.
C.6.2 Rolling stock
The requirements for testing of rolling stock after completion of construction and before entry
into service are set out in Clause 9 of IEC 61133:2006. See also the product standards.
C.6.3 Fixed Installations
Table C.1 – Measurement of the voltage variations and interruptions
Where When How
Ad hoc measurement
• Clauses C.1, C.2, C.3 and C.4 (technical) do not require any specific
At the site, where In response to
type or routine test. However, after the introduction of service, if a
problems are situated. problems
problem is noted which is related to the quality of the voltage, then it is
suggested that the voltage should be monitored over a representative
period after the introduction of full normal service. The results should
be analysed as follows.
• Rapid voltage changes and contact line voltage dips.
Capture voltages below U and analyse data to give voltage level as
min2
a percentage of U and duration in milliseconds.
n
Tabulate worst cases in terms of lowest voltage levels and duration.
Identify any faults or switching on the railway electrification or public
distribution systems at the time of the tabulated changes.
• Short and long interruptions of the voltage
Capture all voltage interruptions and record time of each interruption.
Tabulate voltage interruptions by number in the following time bands:
– < 10 s
– 10 s – 1 min
– 1 min – 3 min
– > 3 min
Give time for any interruptions exceeding 3 min but ignore any pre-
arranged interruptions.
Bibliography
IEC 60038, IEC Standard voltages
IEC 60050-811, International Electrotechnical vocabulary (IEV) – Chapter 811: Electric
traction
IEC 60913, Railway applications – Fixed installations – Electric traction overhead contact
lines
IEC 61992 (all parts), Railway applications – Fixed installations – DC switchgear
IEC 62313, Railway applications – Power supply and rolling stock – Technical criteria for the
coordination between power supply (substation) and rolling stock
IEC 62505 (all parts), Railway applications – Fixed installations – Particular requirements for
a.c. switchgear
EN 50123, all parts, Railway applications – Fixed installations – D.C. switchgear
EN 50124-1, Railway applications – Insulation co-ordination – Part 1: Basic requirements –
Clearances and creepage distances for all electrical and electronic equipment
EN 50124-2, Railway applications – Insulation coordination – Part 2: Overvoltages and related
protection
EN 50152, all parts, Railway applications – Fixed installations – Particular requirements for
a.c. switchgear
EN 50160:1999, Voltage characteristics of electricity supplied by public distribution systems
EN 50163:2004, Railway applications – Supply voltages of traction systems
EN 50388, Railway applications – Power supply and rolling stock – Technical criteria for the
coordination between power supply (substation) and rolling stock to achieve interoperability
UIC 550-OR, Power supply installations for passenger stock
UIC 550-2-OR, Power supply systems for passenger coaches – Type testing
IEEE Std 16, 2004, IEEE Standard for Electrical and Electronic Control Apparatus on Rail
Vehicles
Technical specification for interoperability, TSI Energy subsystem, for conventional rail and
high speed rail in European Union

_____________
– 20 – IEC 60850:2014  IEC 2014
SOMMAIRE
AVANT-PROPOS . 21
1 Domaine d’application . 23
2 Références normatives . 23
3 Termes et définitions . 24
4 Tensions et fréquences des réseaux de traction . 26
4.1 Tensions . 26
4.2 Fréquence . 28
5 Essais . 29
6 Méthodologie d'essai . 29
6.1 Mesure de la tension de la ligne. 29
6.1.1 Matériel roulant . 29
6.1.2 Installations fixes (voir Tableau
...