IEC 62271-102:2001/AMD1:2011

Amendment 1 - High-voltage switchgear and controlgear - Part 102: Alternating current disconnectors and earthing switches

The contents of the corrigendum of January 2012 have been included in this copy.

Amendement 1 - Appareillage à haute tension - Partie 102: Sectionneurs et sectionneurs de terre à courant alternatif

Le contenu du corrigendum de janvier 2012 a été pris en considération dans cet exemplaire.

General Information

• Status: Published
• Publication Date: 18-Aug-2011
• ICS: 29.130.10 - High voltage switchgear and controlgear
• ICS: 29.130.99 - Other switchgear and controlgear
• Technical Committee: SC 17A - Switching devices
• Drafting Committee: MT 43 - TC 17/SC 17C/MT 43
• Current Stage: DELPUB - Deleted Publication
• Start Date: 09-Aug-2019
• Completion Date: 09-Aug-2019

Relations

• Revised: IEC 62271-102:2018 - High-voltage switchgear and controlgear - Part 102: Alternating current disconnectors and earthing switches
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 62271-102

®


Edition 1.0 2011-08



INTERNATIONAL



STANDARD



NORME
INTERNATIONALE
AMENDMENT 1
AMENDEMENT 1


High-voltage switchgear and controlgear –
Part 102: Alternating current disconnectors and earthing switches

Appareillage à haute tension –
Partie 102: Sectionneurs et sectionneurs de terre à courant alternatif


IEC 62271-102:2001/A1:2011

---------------------- Page: 1 ----------------------
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---------------------- Page: 2 ----------------------
IEC 62271-102


®


Edition 1.0 2011-08



INTERNATIONAL



STANDARD



NORME
INTERNATIONALE
AMENDMENT 1
AMENDEMENT 1


High-voltage switchgear and controlgear –
Part 102: Alternating current disconnectors and earthing switches

Appareillage à haute tension –
Partie 102: Sectionneurs et sectionneurs de terre à courant alternatif


INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE PRICE CODE
M
CODE PRIX
ICS 29.130.10; 29.130.99 ISBN 978-2-88912-635-4

® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale

---------------------- Page: 3 ----------------------
– 2 – 62271-102 Amend.1 © IEC:2011



FOREWORD


This amendment has been prepared by subcommittee 17A: High-voltage switchgear and

controlgear, of IEC technical committee 17: Switchgear and controlgear.


The text of this amendment is based on the following documents:


FDIS Report on voting

17A/972/FDIS 17A/978/RVD



Full information on the voting for the approval of this amendment can be found in the report
on voting indicated in the above table.
The committee has decided that the contents of this publication will remain unchanged until
the stability 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.
The contents of the corrigendum of January 2012 have been included in this copy.
_____________
1.2 Normative references
Add the following new references to the existing list:
IEC 62271-1:2007, High-voltage switchgear and controlgear – Part 1: Common specifications
IEC 62271-100:2008, High-voltage switchgear and controlgear – Part 100: Alternating-current
circuit-breakers
3.4.101
disconnector
Replace the content of Notes 1 and 2 as follows:

NOTE 1 "Negligible current" implies currents such as the capacitive currents of bushings, busbars, connections,
very short lengths of cable, currents of permanently connected grading impedances of circuit-breakers and currents
of voltage transformers and dividers (see also IEC 62271-305). For rated voltages of 420 kV and below, a current
not exceeding 0,5 A is a negligible current for the purpose of this definition; for rated voltage above 420 kV and
currents exceeding 0,5 A, the manufacturer should be consulted. "No significant change in voltage" refers to such
applications as the by-passing of induction voltage regulators or circuit-breakers and bus transfer.
NOTE 2 For a disconnector having a rated voltage of 52 kV and above, a rated ability of bus transfer current
switching may be assigned.
3.4.105
earthing switch
Replace the existing text by the following:
IEV 441-14-11 is applicable with the following additional notes
NOTE 101 An earthing switch having a rated voltage of 52 kV and above may have a rating for switching and
carrying induced currents.

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62271-102 Amend.1 © IEC:2011 – 3 –


NOTE 102 These devices may sometimes be operated against short-circuit. The different classes of earthing

switches are related to the number of short-circuit making operations.

NOTE 103 For special applications such as fault initiating earthing switches the test procedures and the number

of tests may be agreed upon between the manufacturer and the user.


3.4.105.1
earthing switch class E0

Replace the existing definition by the following new definition:

earthing switch suitable for applications in distribution and transmission systems fulfilling the
general requirements of this standard, without a short-circuit making capability

3.4.105.2
earthing switch class E1
Replace the existing definition by the following new definition:
earthing switch suitable for applications in distribution and transmission systems fulfilling the
general requirements of this standard, with the capability to withstand two short-circuit making
operations
3.4.105.3
earthing switch class E2
Replace the existing term, definition and note by the following new term, definition and note:
earthing switch class E2 (for earthing switches up to and including 52 kV)
earthing switch suitable for applications in distribution and transmission systems fulfilling the
general requirements of this standard, with the capability to withstand five short-circuit making
operations
NOTE The increased number of making operations in Class E2 is restricted to voltages up to and including 52 kV
only depending on the operating conditions and the protection systems typical to such networks.
Add, after definition 3.4.105.3, the following new definitions 3.4.105.4, 3.4.105.5 and
3.4.105.6:
3.4.105.4
earthing switch class M0 (for earthing switches)
earthing switch suitable for applications in distribution and transmission systems fulfilling the
general requirements of this standard, with the capability to withstand 1 000 operating cycles
3.4.105.5
combined function earthing switch

earthing switch having a common contact system for earthing and at least one of the following
functions:
 disconnecting;
 making and/or breaking of load currents;
 making and/or breaking of currents up to the rated short-circuit current
3.4.105.6
toggle point
point beyond which any further movement of the charging mechanism causes the stored
energy to be released
3.6.106
dependent manual operation (of a mechanical switching device)
Add the following note:

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– 4 – 62271-102 Amend.1 © IEC:2011


NOTE 101 Earthing switches with dependent manual operations should not be rated for short circuit making

capability.

4.5 Rated short-time withstand current (I )

k

Replace the existing text of this subclause by the following new text:


Subclause 4.5 of IEC 62271-1 is applicable with the following addition.


The rated short-time withstand current of an earthing switch forming an integral part of a

combined function earthing switch shall be equal to the rated short-time withstand current of

the combined function earthing switch, unless otherwise specified.

4.6 Rated peak withstand current (I )
p
Replace the existing text of this subclause by the following new text:
Subclause 4.6 of IEC 62271-1 is applicable with the following addition.
The rated peak withstand current of an earthing switch forming an integral part of a combined
function earthing switch shall be equal to the rated peak withstand current of the combined
function earthing switch, unless otherwise specified.
4.101 Rated short-circuit making current
Add the following new text after the existing text of this subclause:
The rated short-circuit making current of an earthing switch forming an integral part of a
combined function earthing switch shall be equal to the rated peak making current of the
combined function earthing switch, unless otherwise specified.
4.107 Rated values of electrical endurance for earthing switches
Replace the existing text by the following new text and Table 7:
Table 3b provides a classification of earthing switch for electrical endurance.
Table 7 – Classification of earthing switch for electrical endurance
Class Type of earthing switch
E0 Earthing switches with no making capability

E1 Earthing switches with capability to withstand two short-circuit making operations
E2 Earthing switches with capability to withstand five short-circuit making operations

6.101 Test to prove the short-circuit making performance of earthing switches
Replace the existing Subclauses 6.101.1, 6.101.2 and 6.101.3 by the following new
Subclauses 6.101.1, 6.101.2, 6.101.3, 6.101.4, 6.101.5, 6.101.6, 6.101.7, 6.101.8, 6.101.9,
6.101.10 and 6.101.11:
6.101.1 General test conditions
Earthing switches of class E1 or E2 according to definition 3.4.105, having a short-circuit
making current capability, shall be subjected to two (class E1) or five (class E2) making
operations respectively, in a making test series in accordance with the procedures of 6.101.7.

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62271-102 Amend.1 © IEC:2011 – 5 –


In case of combined function earthing switches, the short-circuit making tests shall first be

performed in the contact positions for other functions, in accordance with the relevant

standards, followed by the short-circuit making tests of the earthing function, without

intermediate maintenance.


Alternatively, the short-circuit making tests of the combined function earthing switch according

to the specified class can be performed on a new combined function earthing switch preceded

by at least one short-circuit making test of the other function followed by the short-circuit

making tests of the earthing function without intermediate maintenance.


6.101.2 Arrangement of the earthing switch for tests

The earthing switch shall be tested under the representative conditions of installation and
use, concerning the connections, support, enclosure and dimensions.
Its operating device shall be operated in the manner prescribed and in particular, if it is
electrically, hydraulically or pneumatically operated, it shall be operated at the minimum
supply voltage or pressure.
For gas-filled earthing switches, the tests shall be performed at the minimum functional
pressure of the gas for insulation and making operation.
NOTE 1 For convenience of testing the supply voltage to the coil for the closing operation may be increased to
obtain a consistent closing time, provided it does not increase the closing speed of the contacts.
NOTE 2 For convenience of testing in order to obtain accurate closing times an electrically or pneumatically
released latch may be introduced at the toggle point.
NOTE 3 Earthing switches with independent manual operation may be operated by an arrangement provided for
the purpose of making remote control possible.
NOTE 4 For testing purposes, it may be necessary to measure the travel characteristics, for example by using a
travel recorder.
6.101.3 Test frequency
Earthing switches shall be tested at rated frequency, with a tolerance of ± 10 %.
However, tests with a peak factor of 2,6 or above, at a supply frequency of 50 Hz or 60 Hz
cover the requirements of both frequencies.
6.101.4 Test voltage
The test voltage shall be as follows:

a) For three-phase tests, the average value of the applied voltage phase-to-phase shall not
be less than the rated voltage U and shall not exceed this value by more than 10 %
r
without the consent of the manufacturer. The differences between the average value and
the applied voltages of each pole shall not exceed 5 %;
b) For single-phase tests, the applied voltage shall not be less than the phase-to-earth value
U /√3, and shall not exceed this value by more than 10 % without the consent of the
r
manufacturer. For earthing switches with a difference between the instants of contacts
touching during closing exceeding a half of a cycle of the rated frequency, the applied
voltage shall not be less than 1,5 times the phase-to-earth value U /√3 for non-effectively
r
earthed neutral systems and 1,3 times for phase-to-earth value U /√3 for effectively
r
earthed neutral systems.
For convenience of testing or due to limitation of test facilities, alternative test methods can
be followed. The alternative test methods are given in Annex G.

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– 6 – 62271-102 Amend.1 © IEC:2011


6.101.5 Test short-circuit making current


The short-circuit current during making test shall be expressed in terms of the peak current

and the symmetrical r.m.s. current. For earthing switches, the symmetrical r.m.s. value of

current in each phase at 0,2 s shall be at least 80 % of the rated short-time withstand current.

The prospective peak current must be equal to the rated short-circuit making current (I )
ma
with the tolerance of –0 % and +5 %.


The duration of the short-circuit current shall be at least 0,2 s.


The earthing switch shall be able to make the current with the pre-arcing occurring at any

point on the voltage wave. Two extreme cases are specified as follows:
a) making at the peak of the voltage wave, (with a tolerance of -30 electrical degrees to +15
electrical degrees) leading to a symmetrical short-circuit current and the longest pre-
arcing time;
b) making at the zero of the voltage wave, without pre-arcing, leading to a fully asymmetrical
short-circuit current.
NOTE Test b) can be carried out at reduced applied voltage in order to obtain the fully asymmetrical short-circuit
current.
6.101.6 Test circuits
Making tests shall be performed using the three-phase test circuit or the single-phase test
circuit.
Three-phase tests cover:
– the interaction between the different phases;
– the stresses on the operating mechanism (in the case of a common operating
mechanism).
Three-pole earthing switches shall be tested in a three-phase circuit. However, single-phase
testing of earthing switches with rated voltages > 52 kV is allowed in the following cases:
a) multi-enclosure type or open-air type earthing switches with separately stored closing
energy for each pole;
b) earthing switches operated pole-after-pole.
For testing purpose, the severity of making tests in circuits with unearthed neutral or solidly
earthed neutral are considered to be equivalent. Therefore, three-phase short-circuit making
tests may be performed with any one of the test circuits in order to cover applications in both

effectively and non-effectively earthed neutral systems.
6.101.7 Test procedures
For class E1, the tests shall be performed with a sequence of two C-operations with one
single no-load O in between, i.e. C – O(no-load) – C, unless the test laboratory needs more
no-load between the closing operations.
For class E2 earthing switches, the test sequence is 2C – x – 2C – y – 1C, where x and y
represent arbitrary number of no-load tests. The 2C operations consists of
C – O(no-load) – C, unless the test laboratory needs more no-load tests between the closing
operations. There is no requirement on the time interval between the two closing operations.
No maintenance is allowed during a test sequence.
Due to non-simultaneity of poles or different instants of initiation of pre-arcs in the different
poles a peak making current, which is higher than the rated value, may occur in one pole.

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62271-102 Amend.1 © IEC:2011 – 7 –


This is particularly the case if, in one pole, the current begins to flow a few milliseconds later

than in the other two poles. If the earthing switch fails during such an event, this is considered

to be a failure of the earthing switch.


The requirements with regard to the making current and the pre-arcing time as specified in

Table 8 shall be achieved during the tests.


Table 8 – Requirements on making current and pre-arcing time


Class E1 Class E2

2 tests 5 tests

at least 1 test fulfilling the requirements of 6.101.5 a) at least 2 tests fulfilling the requirements of 6.101.5 a)
at least 1 test fulfilling the requirements of 6.101.5 b) at least 2 tests fulfilling the requirements of 6.101.5 b)
NOTE Normally the speed of closing of the contacts of the earthing switches with short-circuit making capability is
high enough that both maximum pre-arcing and maximum peak current can be reached within a same test, however
at different phases.

6.101.8 Behaviour of earthing switches when making short-circuit currents
The following applies during the making tests.
a) Enclosed earthing switches having a rated short-circuit making current shall, when making
the short-circuit, not project flames, liquids, gases nor particles outside the enclosure;
b) Open type earthing switches, flame or metallic particles shall not be projected beyond the
boundaries specified by the manufacturer endangering any operator outside these
boundaries.
6.101.9 Condition of earthing switch after short-circuit making tests
After performing the specified operations, mechanical parts, parts related to the electrical field
control (for example field electrodes of a GIS earthing switch) and insulators of the earthing
switch shall be practically in the same condition as before. The insulating properties shall not
be degraded. The short-circuit making performance and short-time current withstand
performance can be impaired.
NOTE The useful life of the earthing switch with regard to short-circuit making and short time current withstand
capability is normally considered to be at the end, after the specified number of making operations necessitating
maintenance or replacement.
To verify this requirement, the earthing switch shall meet the following inspection conditions:

a) Mechanical conditions: After each operation only light welding of contacts is permitted.
However, the earthing switch shall be able to open and close under the conditions given in
5.5 and 5.6, with the rated values for power operated devices or with 120 % of the values
given for manually operated devices in 5.105 using the normal operating handle;
b) Electrical continuity: Visual inspection after the no-load operation is usually sufficient for
checking the electrical continuity of the earthing switch. In case of doubt the electrical
continuity shall be measured according to 6.10.3 of IEC 62271-1.
c) Dielectric requirements: Visual inspection is usually sufficient for checking the above
requirement. In case of doubt, a voltage test as condition check according to 6.2.11 is to
be performed. As an alternative 6.2.11 of IEC 62271-100 may be used for rated voltages
above 72,5 kV. The minimum functional pressure of the gas for insulation shall be used, if
applicable. For earthing switches which are sealed-for-life, the voltage test as condition
check is mandatory.

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– 8 – 62271-102 Amend.1 © IEC:2011


6.101.10 Invalid tests


In the case of an invalid test, it may become necessary to perform a greater number of short-

circuit making tests than required by this standard. An invalid test is one where one or more

test parameters demanded by the standard are not met. This includes, for example, current,

voltage and time factors as well as point-on-wave requirements (if specified) and the
additional features in synthetic testing.



The deviation from the standard could make the test less or more severe. Four different cases
are considered in Table 9.


The invalid part of the test-duty may be repeated without reconditioning of the earthing switch.
In those cases, the test report shall include reference to the invalid test. However, in the case
of a failure of the earthing switch during such additional tests, or at the discretion of the
manufacturer, the earthing switch may be reconditioned and the complete test-duty repeated.
If any record of an individual operation cannot be produced for technical reasons, individual
operations are not considered invalid, provided that evidence can be given in another manner
that the earthing switch did not fail and the required testing values were fulfilled.
Table 9 – Invalid tests
Test conditions related to Earthing switch passed Earthing switch failed
standard
More severe Test valid, result accepted Test to be repeated with correct
parameters
Modification of the design of the earthing
switch not required
Less severe Test to be repeated with correct Modification of the design of the earthing
parameters switch required, aiming for improvement
of the making capability
Modification of the design of the All tests to be repeated on the modified
earthing switch not required earthing switch

6.101.11 Type test reports
The results of all type tests shall be recorded in type-test reports containing sufficient data to
prove compliance with this rating. Sufficient information should be included so that the
essential parts of the earthing switch tested can be identified. Refer to 6.1.2 of IEC 62271-1.
The test report shall contain the information specified in 6.101.2, 6.101.4, 6.101.5, 6.101.6
and 6.101.7.

Typical oscillographic or similar records shall be provided so that the following can be
determined:
– the making current expressed as a peak value and the r.m.s. value at 0,2 s;
– the applied voltages;
– instantaneous value of voltages at the moment of the making;
– pre-arcing time.
General information concerning the supporting structure of the earthing switch should be
included. Information regarding the operating devices employed during the tests should,
where applicable, be recorded.

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62271-102 Amend.1 © IEC:2011 – 9 –


Annex A – Design and testing of position indicating devices


A.6.105.1.3 Disconnectors and earthing switches with independent power/manual

operation with strain limiting device

Replace the title of the existing Subclause A.6.105.1.3 by the following new title:


A.6.105.1.3 Disconnectors and earthing switches with dependent power/manual
operation with strain limiting device

---------------------- Page: 11 ----------------------
– 10 – 62271-102 Amend.1 © IEC:2011


Add, after the existing Annex F, the following new Annex G:

Annex G

(normative)




Alternative test methods for short-circuit current making tests




G.1 General


In this annex alternative test methods are given to obtain the conditions corresponding to
correct making current with correct pre-arcing time.
For the tests using alternative methods in which the required pre-arcing time is obtained the
making angle can be extended to –40 electrical degrees and +15 electrical degrees with
reference to the voltage peak of the current source.
NOTE At –40 electrical degrees, the pre-arc energy is higher than within the limitation of –30 electrical and +15
electrical degrees.
G.2 Alternative methods
G.2.1 Synthetic test method with both rated voltage and rated short-circuit current
The synthetic test methods as given in Clause 5 of IEC 62271-101 may be applied.
The test circuit and specific requirements shall fulfil the requirement a) of 6.101.5.
G.2.2 Test methods with reduced voltage
To obtain comparable results between tests with rated voltage and alternative test with
reduced voltages, the pre-arcing time obtained during the making test with reduced voltage
shall not be less than the pre-arcing time in the test with the rated voltage.
The test is split up in two parts:
– part 1: a test at rated voltage and reduced current to determine the pre-arcing time of the
earthing switch;
– part 2: a test at reduced voltage and rated short-circuit making current, with the required
pre-arcing time.

G.2.2.1 Part 1: determination of pre-arcing time
The pre-arcing time shall be determined by performing making tests at rated voltage and
reduced current. The arrangement of the earthing switch shall be as described in 6.101.2. The
current shall be low enough that the contact surface is not influenced by contact erosion. The
pre-arcing time shall be determined at each of these tests.
Ten making tests performed to evaluate the pre-arcing time shall result in a current initiation
instant corresponding to an angle of –15 electrical degrees to +15 electrical degrees on the
peak of the applied a.c. voltage wave-shape. The average value of these valid pre-arcing
times measured and the standard deviation (σ) shall be calculated to be applied in Part 2 (see
G.2.2.2).
As an alternative, d.c. voltage may be used. The d.c. voltage shall correspond to the peak
value of the test voltage. The pre-arcing time may differ depending on the polarity of the
voltage at making. Therefore 10 making tests shall be divided into 5 operations with positive

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62271-102 Amend.1 © IEC:2011 – 11 –


polarity and 5 operations with negative polarity. The longest average pre-arcing time out of

the two polarities and its standard deviation (σ) shall be calculated and applied in Part 2.


NOTE Care should be taken to use an appropriate method for measurement of the pre-arcing times, for example

by the use of a travel transducer or an equivalent device. In a three-phase device one phase can be used for

evaluating the pre-arcing time and the other phases can be used to measure the actual contact touch. A no-load
operation with contact timing measurement on all three poles shall be used to compensate time spread between

po
...