IEC 60255-22-5:2008
(Main)Measuring relays and protection equipment - Part 22-5: Electrical disturbance tests - Surge immunity test
Measuring relays and protection equipment - Part 22-5: Electrical disturbance tests - Surge immunity test
IEC 60255-22-5:2008 specifies the general requirements for surge immunity tests for measuring relays and protection equipment for power system protection, including the control, monitoring and process interface equipment used with those systems. Is based on IEC 61000-4-5. The objective of the tests is to confirm that the equipment under test will operate correctly when energized and subjected to high-energy disturbances on the power and interconnection lines, caused by surge voltages from switching and lightning effects. The main change in this new edition concerns line to earth tests.
Relais de mesure et dispositifs de protection - Partie 22-5: Essais d'influence électrique - Essais d'immunité aux ondes de choc
La CEI 60255-22-5:2008 spécifie les exigences générales pour les essais d'immunité aux ondes de choc des relais de mesure et dispositifs de protection des systèmes de protection, en prenant en compte les interfaces avec le processus ainsi que les interfaces de commande et de surveillance utilisés avec ces systèmes. Est basée sur la CEI 61000-4-5. Le but de ces essais est d'obtenir la confirmation que l'équipement à l'essai fonctionnera correctement lorsqu'il sera alimenté et soumis à des perturbations hautement énergétiques sur les lignes d'alimentation et d'interconnexion, causées par des surtensions dues à des commutations et à la foudre. Le principal changement de cette nouvelle édition concerne les tests en mode commun.
General Information
Relations
Standards Content (Sample)
IEC 60255-22-5
Edition 2.0 2008-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Measuring relays and protection equipment –
Part 22-5: Electrical disturbance tests – Surge immunity test
Relais de mesure et dispositifs de protection –
Partie 22-5: Essais d'influence électrique – Essais d'immunité aux ondes de
choc
IEC 60255-22-5:2008
---------------------- Page: 1 ----------------------
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IEC 60255-22-5
Edition 2.0 2008-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Measuring relays and protection equipment –
Part 22-5: Electrical disturbance tests – Surge immunity test
Relais de mesure et dispositifs de protection –
Partie 22-5: Essais d'influence électrique – Essais d'immunité aux ondes de
choc
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
R
CODE PRIX
ICS 29.120.70; 33.100.10; 33.100.20 ISBN 978-2-88910-076-7
® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
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CONTENTS
FOREWORD.3
1 Scope and object.5
2 Normative references .5
3 Terms and definitions .6
4 Test severity level .7
5 Test equipment.8
6 Test set-up .8
6.1 General .8
6.2 Tests applied to auxiliary power supply port .8
6.3 Tests applied to current/voltage transformer inputs .8
6.4 Tests applied to status inputs/output contacts .8
6.5 Tests applied to communications port and other ports using shielded lines.9
7 Test procedure .9
8 Criteria for acceptance .9
9 Test report.10
Bibliography.20
Figure 1 – Ports tested in this standard for measuring relays and protection equipment.7
Figure 2 – Line to earth tests applied to the auxiliary power supply port.11
Figure 3 – Line to line tests applied to the auxiliary power supply port .12
Figure 4 – Line to earth tests applied to current/voltage transformer inputs.13
Figure 5 – Line to line tests applied to current/voltage transformer inputs .14
Figure 6 – Line to earth tests applied to status input/output contacts .15
Figure 7 – Line to line tests applied to status input/output contacts.16
Figure 8 – Line to earth tests applied to communications port and other ports using
shielded cables with the shields grounded at both ends .17
Figure 9 – Line to earth tests applied to communications port and other ports using
shielded cables with the shield connected at one end only.18
Figure 10 – Line to earth tests applied to single and bundled cables in a multi-shield
configuration.19
Table 1 – Test voltages and source impedances for the EUT ports .7
Table 2 – Criteria for acceptance .10
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60255-22-5 © IEC:2008 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
MEASURING RELAYS AND PROTECTION EQUIPMENT –
Part 22-5: Electrical disturbance tests –
Surge immunity test
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
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patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 60255-22-5 has been prepared by technical committee 95:
Measuring relays and protection equipment.
This second edition cancels and replaces the first edition published in 2002. It constitutes a
technical revision. The main change concerns line to earth tests (see Figures 8, 9, 10).
The text of this standard is based on the following documents:
FDIS Report on voting
95/242/FDIS 95/247/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.
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A list of all parts of IEC 60255 series, published under the general title Measuring relays and
protection equipment, 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.
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60255-22-5 © IEC:2008 – 5 –
MEASURING RELAYS AND PROTECTION EQUIPMENT –
Part 22-5: Electrical disturbance tests –
Surge immunity test
1 Scope and object
This part of IEC 60255 is based on IEC 61000-4-5, referring to that publication where
applicable, and specifies the general requirements for surge immunity tests for measuring
relays and protection equipment for power system protection, including the control, monitoring
and process interface equipment used with those systems.
The objective of the tests is to confirm that the equipment under test will operate correctly
when energized and subjected to high-energy disturbances on the power and interconnection
lines, caused by surge voltages from switching and lightning effects.
This standard does not intend to test the capability of the insulation to withstand high-voltage
stress. The insulation test is covered by IEC 60255-27.
The requirements specified in this standard are applicable to measuring relays and protection
equipment in a new condition and all tests specified are type tests only.
The object of this standard is to define:
• terms used;
• test severity levels;
• test equipment;
• test set-up;
• test procedures;
• criteria for acceptance;
• test report requirements.
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 60255-6:1988, Electrical relays – Part 6: Measuring relays and protection equipment
IEC 61000-4-5:2005, Electromagnetic compatibility (EMC) – Part 4-5: Testing and
measurement techniques – Surge immunity test
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3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
equipment under test
EUT
equipment which may be either a measuring relay or a protection equipment
3.2
auxiliary equipment
equipment necessary to provide the EUT with the signals required for normal operation and
equipment to verify the performance of the EUT
3.3
communication port
interface with a communication and/or control system, using low energy signals, permanently
connected to the EUT
3.4
input port
port through which the EUT is energised or controlled in order to perform its function(s), for
example current and voltage transformer, status (binary) inputs, etc.
3.5
interconnection lines
these consist of input/output lines, communication lines and balanced lines
3.6
output port
port through which the EUT produces predetermined changes, for example contact,
optocoupler, analogue outputs, etc.
3.7
port
particular interface of the EUT with the external electromagnetic environment (see Figure 1)
3.8
auxiliary power supply port
AC or DC auxiliary energising input of the EUT
3.9
transient
pertaining to or designating a phenomenon or a quantity which varies between two
consecutive states during a time interval short compared with the time-scale of interest
[IEV 161-02-01]
3.10
surge
a transient wave of electrical current, voltage or power propagating along a line or a circuit
and characterized by a rapid increase followed by a slower decrease
[IEV 161-08-11, modified]
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60255-22-5 © IEC:2008 – 7 –
Auxiliary power supply port Output port
EUT
Input port Communication port
IEC 2082/08
Figure 1 – Ports tested in this standard for measuring relays and protection equipment
4 Test severity level
The test voltages and coupling network for the appropriate ports are shown in Table 1.
Table 1 – Test voltages and source impedances for the EUT ports
a
Test conditions line to earth Test conditions line to line
Coupling
Open-circuit test Open-circuit Coupling
c c
voltage network test voltage network
Ports under test
±10 % ±10 %
R C R C
kV kV
Ω μF Ω μF
Auxiliary power supply 0,5 1,0 2,0 10 9 0,5 1,0 0 18
a a
Input /output 0,5 1,0 2,0 40 0,5 0,5 1,0 40 0,5
b
Communication 0,5 1,0 0 0 No test – –
a
No line to line test is advised on input/output ports which, according to the manufacturers functional
specification, are always interfacing with twisted pair screened cables.
The application of the surge is to simulate a lightning strike and hence the surge is a short duration high
energy pulse. This pulse may cause low impedance high sensitivity circuits, for example current
transformers, to produce a start signal when it is applied. If this is the case and the relay has interpreted the
pulse correctly as per their design, then the manufacturer shall state any time delays or setting limitations
which should be applied to ensure immunity to the surge pulse.
b
Not applicable for optical fibre communications and EUT communication ports where the specified cable
length is less than 10 m as given in the EUT’s specification.
c
Alternative methods of coupling networks are allowed as described in IEC 61000-4-5, for example gas
arrestors, where the coupling capacitor would have an effect on the operation of the circuit.
The test procedure shall consider the non-linear current-voltage characteristics of the EUT.
Thus, the test voltage has to be increased in the steps specified in Table 1 from the lowest
level to the highest, with the criteria for acceptance being met at each level.
The test voltage waveform shall be 1,2/50 μs under open-circuit conditions and the current
waveform shall be 8/20 μs under short-circuit conditions.
Unless otherwise stated, no test is advised for ports interfacing with cables whose total length
according to the manufacturers documentation is always less than 10 m.
NOTE For more severe environments, a severity level of 4 kV for common mode and 2 kV for differential mode
may be agreed between manufacturer and user.
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5 Test equipment
The test equipment is described in IEC 61000-4-5:2005, Clause 6. This includes a description
of the test generator, the verification of the characteristics (IEC 61000-4-5:2005, 6.1), and the
coupling/decoupling networks (IEC 61000-4-5:2005, 6.3).
NOTE Particular EUTs may not operate correctly with the decoupling inductances as specified in IEC 61000-4-5.
In such cases, the use of decoupling inductances less than the specified values is allowed. The exact value of the
inductances used during the surge testing should be stated in the test report.
6 Test set-up
6.1 General
The general test set-ups are specified in IEC 61000-4-5:2005, Clause 7.
All auxiliary equipment used to provide the EUT with signals for normal operation, and to
verify the correct operation of the EUT, shall be decoupled, so that the test voltage does not
affect the auxiliary equipment. These decoupling networks shall also provide sufficient
decoupling so that the specified test waveform may be developed only on the lines under test
and does not significantly affect the open-circuit voltage or short-circuit current of the test
generator.
The connections between the EUT and the test generator shall be less than 2 m, and, except
in the case of the testing of the communications port (see Figure 8), connections between the
EUT and the coupling/decoupling networks shall also be less than 2 m.
Normally, the EUT shall be individually tested with the EUT placed on an insulating support
0,1 m above the ground reference plane, and all parts of the EUT shall be at least 0,5 m from
any metallic obstacles. If the EUT is to be tested on a non-conducting table, normally 0,8 m
high, the ground reference plane may be placed on the table.
Where the EUT is exclusively mounted in a cubicle, the tests may be conducted with the EUT
in the cubicle. No surge test shall be performed on the interconnecting cables between EUT
which are completely within the cubicle, these being regarded as internal cables of the
system. The cubicle should be placed on an insulating support, 0,1 m above the ground
reference plane. Interconnecting cables greater than 1 m in length belonging to the EUT shall
remain on the insulating support.
Specific details for measuring relays and protection equipment are as given below.
6.2 Tests applied to auxiliary power supply port
See Figures 2 and 3 for examples of a typical test set-up. The values for the coupling/decoupling
networks are in line with 6.3.1 and 7.2 of IEC 61000-4-5:2005.
6.3 Tests applied to current/voltage transformer inputs
See Figures 4 and 5 for examples of a typical test set-up. The values for the coupling/decoupling
networks are in line with 6.3.2 and 7.3 of IEC 61000-4-5:2005.
Synchronization of the application of the surge voltage with any a.c. waveforms on the current
or voltage inputs is not required.
6.4 Tests applied to status inputs/output contacts
See Figures 6 and 7 for examples of a typical test set-up. The values for the coupling/decoupling
networks are in line with 6.3.2 and 7.3 of IEC 61000-4-5:2005.
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60255-22-5 © IEC:2008 – 9 –
6.5 Tests applied to communications port and other ports using shielded lines
See Figures 8 and 9 for the test set-up for shields grounded at both ends and at one end
respectively.
See Figure 10 for the test set-up for testing single and bundled cables in a multi-shield
configuration.
This coupling method is useful for multiple shielded cable wiring with multiple ground
connections, in order to apply the surge to, either a particular cable or bundle of cables,
depending on how they are bundled in an installation.
7 Test procedure
The tests shall be carried out at the reference conditions given in IEC 60255-6.
Time delay settings of the EUT shall be set to their minimum practical values as defined by
their intended application.
The tests shall be carried out with auxiliary energizing quantities applied to the
appropriate circuits, with values equal to rated conditions. The values of the input
energizing quantities shall be within twice the assigned error of the transitional state. For
practical reasons, the application of the surge test to the EUT in the transitional or
operational state is not considered.
If the rated conditions of the EUT mean that the input energizing quantity is much lower
than the relay operational value, the tests shall be performed at the continuous thermal
withstand value.
The surges shall be applied line to line(s) and line to earth. When testing line to earth, the test
voltage shall be applied successively between each of the lines and earth.
Where a port consists of many identical circuits, such as status inputs or output contacts, it is
sufficient to apply the surge test only to three such circuits in order for the criteria for
acceptance to be met.
Because of the possibility that the EUT has non-linear current-voltage characteristics, all
lower test voltages up to and including the maximum test voltage shall be satisfied as
shown in Table 1.
In the case of testing a.c. auxiliary power supply inputs, the surges shall be applied
synchronized to the voltage phase at the zero crossing and the peak value of the a.c. voltage
wave, both positive and negative.
The number of tests shall be at least five positive and five negative surges at the selected
points. The repetition rate shall be a maximum of 1 surge/min.
8 Criteria for acceptance
The test result is positive if the EUT shows its immunity for all the period of the application of
the tests, and, after the test has been completed, the EUT shall still comply with the relevant
performance specification.
Table 2 lists the important functions that could apply to a measuring relay or protection
equipment. These should be monitored during testing.
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Table 2 – Criteria for acceptance
Function Criteria for acceptance
Protection Normal performance within the specification limits
Command and control Normal performance within the specification limits
Measurement Temporary degradation during test, with self-recovery at the end
of the test. No loss of stored data
Integral human-machine interface and Temporary degradation or loss of function during the test, with self-
visual alarms recovery at end of the test. No loss of stored data
Data communication Possible bit error rate increase but no loss of transmitted data
9 Test report
The test report shall include those items listed in 60255-6 and also the following:
• the identification and configuration of the EUT;
• the test conditions including the repetition rate;
• the type of test facility used and the positions of the EUT, auxiliary equipment and
coupling and decoupling devices;
• the type(s) and number of interconnecting wires used and the interface port (of the EUT)
to which these are connected;
• the values of the decoupling inductances when these vary from the recommended values;
• the operating conditions of the EUT, for example, relay settings and values of input
energizing quantities;
• the test equipment used;
• the test conclusion (pass/fail).
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60255-22-5 © IEC:2008 – 11 –
Test generator
R = 10 Ω
Coupling
network
C = 9 μF
Decoupling
network
EUT
L
Auxiliary
power
supply
network
L = 1,5 mH
Insulating support
Ground reference plane
IEC 2083/08
Figure 2 – Line to earth tests applied to the auxiliary power supply port
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– 12 – 60255-22-5 © IEC:2008
Test generator
R = 0 Ω
Coupling
network
C = 18 μF
Decoupling
network
EUT
L
Auxiliary
power
supply
network
L = 1,5 mH
Insulating support
Ground reference plane
IEC 2084/08
Figure 3 – Line to line tests applied to the auxiliary power supply port
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60255-22-5 © IEC:2008 – 13 –
Test generator
R = 40 Ω
Coupling
network
C = 0,5 μF
Auxiliary Decoupling
equipment network
EUT
L
L
L
L
L
L = 20 mH
Insulating support
Ground reference plane
IEC 2085/08
Figure 4 – Line to earth tests applied to current/voltage transformer inputs
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– 14 – 60255-22-5 © IEC:2008
Test generator
R = 40 Ω
Coupling
network
C = 0,5 μF
Auxiliary Decoupling
equipment network
EUT
L
L
L
L
L
L = 20 mH
Insulating support
Ground reference plane
IEC 2086/08
Figure 5 – Line to line tests applied to current/voltage transformer inputs
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60255-22-5 © IEC:2008 – 15 –
Test generator
R = 40 Ω
Coupling
network
C = 0,5 μF
Auxiliary Decoupling
equipment network
EUT
L
n
L
2
L
1
L = 20 mH
Common
Insulating support
Ground reference plane
IEC 2087/08
Figure 6 – Line to earth tests applied to status input/output contacts
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Test generator
R = 40 Ω
Coupling
network
C = 0,5 μF
Auxiliary Decoupling
equipment network
EUT
L
n
L
2
L
1
L = 20 mH
Common
Insulating support
Ground reference plane
IEC 2088/08
Figure 7 – Line to line tests applied to status input/output contacts
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60255-22-5 © IEC:2008 – 17 –
Safety isolation Safety isolation
transformer or CDN transformer or CDN
L L
Auxiliary
N N
equipment
PE PE
EUT
L = maximum of 20 m
Generator
Ground reference plane
IEC 2089/08
Figure 8 – Line to earth tests applied to communications port and other ports using
shielded cables with the shields grounded at both ends
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Safety isolation Safety isolation
transformer or CD
...
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