IEC TS 62271-319:2024

IEC TS 62271-319 ®
Edition 1.0 2024-09
TECHNICAL
SPECIFICATION
High-voltage switchgear and controlgear –
Part 319: Alternating current circuit-breakers intended for controlled switching

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IEC TS 62271-319 ®
Edition 1.0 2024-09
TECHNICAL
SPECIFICATION
High-voltage switchgear and controlgear –

Part 319: Alternating current circuit-breakers intended for controlled switching

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.130.10; 29.130.99 ISBN 978-2-8322-9580-9

– 2 – IEC TS 62271-319:2024 © IEC 2024
CONTENTS
FOREWORD . 7
INTRODUCTION . 9
1 Scope . 10
2 Normative references . 10
3 Terms and definitions . 11
3.1 General terms and definitions . 11
3.2 Assemblies of switchgear and controlgear . 11
3.3 Parts of assemblies . 11
3.4 Switching devices . 11
3.5 Parts of switchgear and controlgear . 11
3.6 Operational characteristics of switchgear and controlgear . 11
3.7 Characteristic quantities . 12
4 Normal and special service conditions . 17
5 Ratings . 17
5.1 General . 17
5.2 Rated short-circuit making current (I ) for intentional non-simultaneous
mc
closing . 17
6 Design and construction . 19
6.1 General . 19
6.2 Mechanical scatter . 19
6.3 RDDS . 19
6.4 Auxiliary and control equipment and circuits . 19
6.5 Uncontrolled operations . 19
6.6 Nameplates. 19
6.7 Simultaneity of poles during closing and opening operations . 19
6.7.1 Single-pole operated circuit-breakers intended for controlled switching . 19
6.7.2 Mechanically staggered circuit-breakers intended for controlled
switching . 19
6.7.3 Non-simultaneity between individual making and breaking units (MBUs)
of a pole . 20
7 Type tests . 20
7.1 General . 20
7.2 Miscellaneous provisions for making and breaking tests . 21
7.2.1 General . 21
7.2.2 Identical nature of the MBUs . 21
7.2.3 Test duty T100a . 21
7.2.4 Short-circuit making current . 24
7.3 Capacitive current making and breaking tests . 24
7.3.1 General . 24
7.3.2 Test voltage to verify controlled opening in non-effectively earthed
neutral systems . 24
7.3.3 Test-duty to verify controlled opening in non-effectively earthed neutral
systems . 25
7.3.4 Test-duty to verify controlled switching of back-to-back capacitor banks . 25
7.4 Determination of the chopping characteristics and RRDS for inductive load
switching . 25
7.5 Controlled closing test . 26

7.5.1 Applicability . 26
7.5.2 General requirements . 26
7.5.3 Specified target point for closing defined by the manufacturer . 27
7.5.4 Characteristics of the power frequency supply circuit . 27
7.5.5 Test procedure – general requirements . 27
8 Routine tests . 28
8.1 General . 28
9 Guide to the selection of switchgear and controlgear for service (informative) . 28
9.1 General . 28
9.2 Voltage factors based on system configuration . 28
9.3 Mechanical and electrical characteristics of the circuit-breaker . 29
9.3.1 Reference mechanical travel characteristics . 29
9.3.2 Mechanical characteristics of the circuit-breaker as a function of

environmental and operating conditions . 29
9.4 Effect of RDDS and mechanical scatter on target determination . 29
10 Information to be given with enquiries, tenders and orders (informative) . 29
10.1 General . 29
11 Transport, storage, installation, operation instructions and maintenance. 30
11.1 General . 30
11.2 Commissioning of circuit-breakers for controlled switching . 30
11.3 Maintaining controlled switching accuracy . 30
12 Safety . 30
13 Influence of the product on the environment . 30
Annex A (informative) Parameter definition summary test report . 31
A.1 General . 31
A.2 Information to be included in the parameter definition summary test report . 31
A.2.1 General information . 31
A.2.2 Parameter definition tests . 31
Annex B (informative) Determination of mechanical scatter . 34
B.1 Applicability . 34
B.2 Test procedure . 34
B.3 Test results . 35
Annex C (informative) Determination of the rate of decrease of dielectric strength
(RDDS) . 36
C.1 Applicability . 36
C.2 General . 36
C.3 Test procedure . 37
C.3.1 Preferred test procedure . 37
C.3.2 Alternative test procedure . 37
C.4 Test results . 37
Annex D (informative) Impact of control voltage . 38
D.1 Applicability . 38
D.2 General . 38
D.3 Test procedure . 38
D.4 Test results . 38
Annex E (informative) Impact of low temperature . 39
E.1 Applicability . 39
E.2 General . 39

– 4 – IEC TS 62271-319:2024 © IEC 2024
E.3 Test procedure . 39
E.4 Test results . 39
Annex F (informative) Impact of high temperature . 40
F.1 Applicability . 40
F.2 General . 40
F.3 Test procedure . 40
F.4 Test results . 40
Annex G (informative) Impact of pressure for operation . 41
G.1 Applicability . 41
G.2 General . 41
G.3 Test procedure . 41
G.4 Test results . 41
Annex H (informative) Impact of pressure for insulation and/or switching . 42
H.1 Applicability . 42
H.2 General . 42
H.3 Test procedure . 42
H.4 Test results . 42
Annex I (informative) Impact of idle time . 43
I.1 Applicability . 43
I.2 General . 43
I.3 Test procedure . 44
I.4 Test results . 44
Annex J (informative) Impact of electrical wear on the accuracy of auxiliary contacts . 45
J.1 Applicability . 45
J.2 General . 45
J.3 Test procedure . 45
J.4 Test results . 45
Annex K (informative) Effects of RDDS and mechanical scatter on voltage targeting . 46
K.1 Introduction to controlled making . 46
K.2 Abbreviations used in this annex . 47
K.3 Controlled closing at voltage zero . 48
K.4 Controlled closing at voltage peak . 50
K.5 Making at variable angles . 52
K.6 Making on a DC trapped charge . 53
K.7 Making on an oscillatory trapped charge . 55
K.8 Synthesis . 56
Annex L (informative) Capacitive switching voltage factor for single-phase testing in a
non-effectively earthed neutral system. 57
L.1 General . 57
L.2 Simultaneous opening simulation results. 57
L.3 Non-simultaneous opening simulation results . 58
Annex M (informative) Requirements for simultaneity of poles that consists of more
than one MBU connected in series . 59
M.1 General . 59
M.2 Simulations to evaluate the impact of non-simultaneity of MBUs of a same
pole . 59
Annex N (informative) Mechanical parameter definition tests combined with
mechanical operation tests as per IEC 62271-100 . 64

Annex O (normative) Correction of di/dt and TRV for synthetic testing for test duty
T100a . 66
O.1 General . 66
Bibliography . 75

Figure 1 – Example of a controlled opening operation . 14
Figure 2 – Example of a controlled closing operation . 15
Figure 3 – Current interruption definitions in a switching device . 16
Figure 4 – Target definitions for a controlled closing operation in the vicinity of voltage
peak . 16
Figure 5 – Target definitions for a controlled closing operation in the vicinity of voltage
zero . 17
Figure 6 – Last half cycle current loop during reactor switching . 26
Figure I.1 – Illustration of idle time for a close and open operation . 44
Figure K.1 – Closing and making sequence for a gas circuit-breaker. 46
Figure K.2 – "Balanced" method for voltage zero making . 48
Figure K.3 – "Tangent" method for voltage zero making . 49
Figure K.4 – Controlled switching at peak voltage, balanced approach . 51
Figure K.5 – Controlled switching at peak voltage, maximum angle method . 51
Figure K.6 – Making at variable angles . 53
Figure K.7 – Minimum limits RDDS and making angle . 53
Figure K.8 – Making on a DC trapped charge of 1 p.u. . 54
Figure K.9 – Reclosing on an oscillatory trapped charge . 55
Figure L.1 – Three-phase interruption at subsequent current zeros . 57
Figure L.2 – Three-phase interruption with last poles delayed . 58
Figure M.1 – Closing time distribution and non-simultaneity between MBUs of one pole . 60
Figure M.2 – Simulation results when closing at voltage zero at 50 Hz . 61
Figure M.3 – Simulation results when closing at voltage zero at 60 Hz . 61
Figure M.4 – Simulation results when closing at voltage peak at 50 Hz . 62
Figure M.5 – Simulation results when closing at voltage peak at 60 Hz . 62

Table 1 – Peak making factors for the short-circuit making current for circuit-breakers
for use in non-effectively earthed neutral systems or isolated neutral capacitive loads
when closing the first two poles at zero phase-to-phase voltage and the third pole 90°
later 18
Table 2 – Short-circuit making current de-rating factors in non-effectively earthed
neutral systems when closing the first two poles at zero phase-to-phase voltage and
the third pole 90° later . 18
Table 3 – Type tests for circuit-breakers intended for controlled switching . 21
Table 4 – Last current loop parameters in three-phase tests and in single-phase tests
in substitution for three-phase conditions in relation with short-circuit test-duty T100a

in non-effectively earthed neutral systems – Tests for 50 Hz operation . 22
Table 5 – Last current loop parameters in three-phase tests and in single-phase tests
in substitution for three-phase conditions in relation with short-circuit test-duty T100a
in non-effectively earthed neutral systems – Tests for 60 Hz operation . 23
Table 6 – Voltage factors depending on earthing conditions . 29
Table D.1 – Tests to assess the impact of control voltage . 38

– 6 – IEC TS 62271-319:2024 © IEC 2024
Table K.1 – Examples of U equal to 1 p.u. . 47
pe
Table K.2 – Examples of RDDS equal to 1 p.u. . 48
Table K.3 – Maximum making voltage as a function of RDDS and mechanical scatter at
50 Hz . 49
Table K.4 – Maximum making voltage as a function of RDDS and mechanical scatter at

60 Hz . 50
Table K.5 – Minimum making angle as a function of RDDS and mechanical scatter
when targeting voltage peak at 50 Hz . 52
Table K.6 – Minimum making angle as a function of RDDS and mechanical scatter
when targeting voltage peak at 60 Hz . 52
Table K.7 – Making voltage when closing on a DC trapped charge of 1 p.u. at 50 Hz . 54
Table K.8 – Making voltage when closing on a DC trapped charge at 60 Hz . 55
Table K.9 – Controlled closing target . 56
Table M.1 – Case studies based on statistical simulations . 60
Table M.2 – Combined results, making window with 99 % probability . 63
Table N.1 – Comparison between mechanical parameter definition tests and the
mechanical operation test as per IEC 62271-100 . 64
Table N.2 – Combination of the mechanical parameter definition tests and the
mechanical operation test as per IEC 62271-100 . 65
Table O.1 – Corrected TRV values for the first pole-to-clear for k = 1,5 and
pp
f = 50 Hz . 66
r
Table O.2 – Corrected TRV values for the first pole-to-clear for k = 1,5 and
pp
f = 60 Hz . 67
r
Table O.3 – Percentage of DC component and di/dt at current zero for first pole-to-
clear for k = 1,5 and f = 50 Hz . 69
pp r
Table O.4 – Percentage of DC component and di/dt at current zero for first pole-to-
clear for k = 1,5 and f = 60 Hz . 70
pp r
Table O.5 – Required test parameters for different asymmetrical conditions in the case
of k = 1,5 and f = 50 Hz . 71
pp r
Table O.6 – Required test parameters for different asymmetrical conditions in the case
of k = 1,5 and f = 60 Hz . 73
pp r
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
HIGH-VOLTAGE SWITCHGEAR AND CONTROLGEAR –

Part 319: Alternating current circuit-breakers
intended for controlled switching

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
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3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
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6) All users should ensure that they have the latest edition of this publication.
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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) IEC draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). IEC takes no position concerning the evidence, validity or applicability of any claimed patent rights in
respect thereof. As of the date of publication of this document, IEC had not received notice of (a) patent(s), which
may be required to implement this document. However, implementers are cautioned that this may not represent
the latest information, which may be obtained from the patent database available at https://patents.iec.ch. IEC
shall not be held responsible for identifying any or all such patent rights.
IEC TS 62271-319 has been prepared by subcommittee 17A: Switching devices, of IEC
technical committee 17: High-voltage switchgear and controlgear. It is a Technical Specification.
The text of this Technical Specification is based on the following documents:
Draft Report on voting
17A/1404/DTS 17A/1411/RVDTS
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this Technical Specification is English.

– 8 – IEC TS 62271-319:2024 © IEC 2024
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.
This document is to be read in conjunction with IEC 62271-100:2021, to which it refers and
which is applicable unless otherwise specified.
A list of all parts of IEC 62271 series, under the general title High-voltage switchgear and
controlgear, can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn, or
• revised.
IMPORTANT – The "colour inside" logo on the cover page of this document indicates
that it contains colours which are considered to be useful for the correct understanding
of its contents. Users should therefore print this document using a colour printer.

INTRODUCTION
This part of IEC 62271, which is a Technical Specification, clearly segregates normative
requirements which are presented in the main text, from informative and advisory information
which is presented in a series of annexes. Using this approach all information pertaining to the
topic of circuit-breakers intended for controlled switching can be consolidated into this single
reference document. The IEC considers that this approach best meets the market need by
presenting all relevant information in the most concise and readily usable form.
For the purposes of this document, it has been assumed that there is no significant interaction
between the effects of the various parameters (for example ambient temperature, control
voltage, etc.) which are considered to affect the mechanical performance of the circuit-breaker.
This has not been proven for all combinations, however service experience with controlled
switching suggests this assumption is valid in practice for commonly used drive technologies.

– 10 – IEC TS 62271-319:2024 © IEC 2024
HIGH-VOLTAGE SWITCHGEAR AND CONTROLGEAR –

Part 319: Alternating current circuit-breakers
intended for controlled switching

1 Scope
This part of IEC 62271, which is a Technical Specification, is applicable to alternating current
circuit-breakers with intentional non-simultaneous pole operation designed for indoor or outdoor
installations and for operation at frequencies of 50 Hz and 60 Hz on systems having voltages
above 1 000 V. This document provides additional ratings and type tests to be conducted for
this type of circuit-breaker and is intended to be used in conjunction with IEC 62271-100:2021.
Intentional non-simultaneous pole operation can be implemented by mechanical or electrical
means and both methods are within the scope of this document.
Satisfactory service performance of controlled switching systems is influenced by the inherent
performance capabilities of the switching device and by the choice of a suitable controller (relay)
and requires proper integration of these devices. Consequently, practical applications of
controlled switching require a coordinated approach to system integration.
This document addresses the performance capabilities of the switching device and establishes
suitability for controlled switching when applied with an appropriate controller. Type tests are
defined, and guidance is provided to establish the switching device capabilities and parameters
required to facilitate proper system integration, but this document does not address the
performance requirements of the controller. In summary, compliance and testing in accordance
with the requirements and guidance presented herein verify the ability of the switching device
to meet defined switching accuracy requirements only when applied with a suitably specified
controller.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements 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 60050-441:1984, International Electrotechnical Vocabulary (IEV) – Part 441: Switchgear,
controlgear and fuses
IEC 60050-441:1984/AMD1:2000
IEC 62271-1, High-voltage switchgear and controlgear – Part 1: Common specifications for
alternating current switchgear and controlgear
IEC 62271-100:2021, High-voltage switchgear and controlgear – Part 100: Alternating-current
circuit-breakers
IEC 62271-100:2021/AMD1:2024
IEC 62271-101:2021, High-voltage switchgear and controlgear – Part 101: Synthetic testing
IEC 62271-110, High-voltage switchgear and controlgear – Part 110: Inductive load switching

IEC TR 62271-306:2012, High-voltage switchgear and controlgear – Part 306: Guide to
IEC 62271-100, IEC 62271-1 and other IEC standards related to alternating current circuit-
breakers
IEC TR 62271-306:2012/AMD1:2018
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60050-441 and
IEC 62271-100 and the following apply.
ISO and IEC maintain terminology databases for use in standardization at the following
addresses:
• IEC Electropedia: available at https://www.electropedia.org/
• ISO Online browsing platform: available at https://www.iso.org/obp
3.1 General terms and definitions
3.1.101
idle time
time interval between consecutive operations (either between a close and open or open and
close operation)
3.1.102
compensation
predictive correction for changes in operating time taking account of ambient, drive and supply
conditions
3.2 Assemblies of switchgear and controlgear
3.2.101
controlled switching system
combination of circuit-breaker, controller and necessary sensors and auxiliary equipment
required to achieve controlled switching as defined in 3.6.101
Note 1 to entry: Necessary sensors refers to those required to provide inputs to the controlled system and may
include voltage transformers, current transformers, temperature sensors etc.
3.3 Parts of assemblies
No particular definitions.
3.4 Switching devices
No particular definitions.
3.5 Parts of switchgear and controlgear
No particular definitions.
3.6 Operational characteristics of switchgear and controlgear
3.6.101
controlled switching
intended operation of a circuit-breaker at a specific, pre-determined point in relation to the
power frequency current or voltage
Note 1 to entry: The terms point-on-wave switching and point-on-cycle switching are also in widespread use to
describe controlled switching.

– 12 – IEC TS 62271-319:2024 © IEC 2024
3.6.102
intentional non-simultaneous pole operation
operation of a circuit-breaker with a specific, pre-determined time delay or delays between the
operation of the individual poles
Note 1 to entry: Non-simultaneity is typically measured and expressed in electrical degrees with relation to the
phase taken as reference e.g. 0°, 0°, 90° for each pole.
3.6.103
mechanically staggered circuit-breaker
circuit-breaker with fixed, mechanically implemented, non-simultaneous pole operation
3.6.104
controller
device used to define the instant of switching of a circuit-breaker and to operate each pole
independently according to a predefined sequence
3.7 Characteristic quantities
3.7.101
opening time

interval of time between the specified instant of initiation of the opening operation and the
instant when the arcing contacts have separated in all poles
Note 1 to entry: The instant of initiation of the opening operation, i.e. the application of the opening command (for
example energizing the release, etc.) is given in the relevant specification.
Note 2 to entry: Time from the instant of coil energization to arcing contact separation. Any delay introduced by a
controller is not considered.
[SOURCE: IEC 60050-441:1984+AMD1:2000, 441-17-36, modified – Notes 1 and 2 to entry
added]
3.7.102
closing time
interval of time between the initiation of the closing operation and the instant when the contacts
touch in all poles
Note 1 to entry: Time from the instant of coil energization to arcing contact touch. Any delay introduced by a
controller is not considered.
[SOURCE: IEC 60050-441:1984+AMD1:2000, 441-17-41, modified – Note 1 to entry added]
3.7.103
close-open time
interval of time between the instant when the arcing contacts touch in the first pole during a
closing operation and the instant when the arcing contacts have separated in all poles during
the subsequent opening operation
[SOURCE: IEC 60050-441:1984+AMD1:2000, 441-17-42, modified – addition of "arcing"]
3.7.104
minimum close-open clearing time
sum of the minimum close-open time when a trip command comes after a minimum relay time
of half a cycle after the arcing contacts touch in the first two poles during a closing operation
and the shortest arcing time of a minor loop breaking in the last phase to make
Note 1 to entry: For convenience of testing, the manufacturer may declare that the minimum close-open clearing
time is equal to sum of the minimum close-open time and the shortest arcing time of a minor loop breaking in the last
phase to make.
3.7.105
mechanical scatter
random statistical variation of the mechanical operating time of a circuit-breaker, given by the
±3σ interval at rated conditions, excluding the influence of external variables and the effect of
long-term wear and/or drift
Note 1 to entry: For the purposes of this definition the term "external variables" includes all variables which could
have a systematic effect on the operating time for example ambient temperature, operating pressure, control voltage.
3.7.106
rate-of-decrease of dielectric strength
RDDS
voltage withstand reduction as a function of time or arcing contacts gap during closing of a
circuit-breaker
3.7.107
rate-of-rise of dielectric strength
RRDS
voltage withstand increase as a function of time or arcing contacts gap during opening of a
circuit-breaker
3.7.108
re-ignition free arcing time window
period of arc duration during a breaking operation during which the arcing contacts of a
mechanical switching device reach sufficient distance to exclude re-ignition
3.7.109
target point for opening
prospective instant of arcing contact separation during a controlled opening operation of a
circuit-breaker
3.7.110
target point for closing
prospective instant of arcing contact touch during a controlled closing operation of a circuit-
breaker
3.7.111
target point for making
prospective instant of current initiation during a controlled closing operation of a circuit-breaker
3.7.112
making window
time interval around the target point for making
Note 1 to entry: Making within a correctly chosen making window will lead to a pre-determined making voltage. For
practical values of RDDS, the centre of the making window may not correspond to the t
...