IEC TS 62271-313:2025

IEC TS 62271-313 ®
Edition 1.0 2025-03
TECHNICAL
SPECIFICATION
High-voltage switchgear and controlgear –
Part 313: Direct current circuit-breakers

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IEC TS 62271-313 ®
Edition 1.0 2025-03
TECHNICAL
SPECIFICATION
High-voltage switchgear and controlgear –

Part 313: Direct current circuit-breakers

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.130.10  ISBN 978-2-8327-0292-5

– 2 – IEC TS 62271-313:2025 © IEC 2025
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 . 12
3.3 Parts of assemblies . 12
3.4 Switching devices . 12
3.5 Parts of switchgear and controlgear . 16
3.6 Operational characteristics of DC circuit-breaker . 20
3.7 Characteristic quantities . 21
3.8 Index of definitions . 26
4 Normal and special service conditions . 28
5 Ratings . 28
5.1 General . 28
5.2 Rated direct voltage (U ) . 29
rd
5.2.1 General . 29
5.2.2 Rated voltages . 29
5.3 Rated insulation level (U , U , U ) . 29
dd p s
5.4 Rated continuous current (I ) . 29
rd
5.5 Rated values of short-time withstand current . 29
5.5.1 Typical waveform of short-circuit current . 29
5.5.2 Rated short-time withstand direct current (I ) . 29
kd
5.5.3 Rated peak withstand current (I ) . 29
pd
5.5.4 Rated duration of short circuit (t ) . 29
kd
5.6 Rated supply voltage of auxiliary and control circuits (U ) . 29
a
5.6.1 General . 29
5.6.2 Rated supply voltage (U ) . 29
a
5.7 Rated supply frequency of auxiliary and control circuits . 29
5.101 Rated operating sequence . 30
5.102 Rated short-circuit breaking current (I ) . 30
scd
5.103 Rated short-circuit making current . 30
5.104 Rated dissipated energy during breaking operation . 30
6 Design and construction . 30
6.1 Requirements for liquids in DC circuit-breaker . 30
6.2 Requirements for gases in DC circuit-breaker . 30
6.3 Earthing of DC circuit-breaker . 30
6.4 Auxiliary and control equipment and circuits . 31
6.5 Dependent power operation . 31
6.6 Stored energy operation . 31
6.7 Independent unlatched operation (independent manual or power operation) . 31
6.8 Manually operated actuators . 31
6.9 Operation of releases . 31

6.10 Pressure/level indication . 31
6.11 Nameplates. 31
6.12 Locking devices . 32
6.13 Position indication . 33
6.14 Degrees of protection provided by enclosures . 33
6.15 Creepage distances for outdoor insulators . 33
6.16 Gas and vacuum tightness . 33
6.17 Tightness for liquid systems . 33
6.18 Fire hazard (flammability) . 33
6.19 Electromagnetic compatibility (EMC) . 33
6.20 X-ray emission . 33
6.21 Corrosion . 33
6.22 Filling levels for insulation, switching and/or operation . 33
6.101 Static mechanical load . 33
6.102 Metal oxide surge arrester (MOSA) . 34
6.103 Power to potential device (if applicable) . 34
6.104 Liquid cooling system (if applicable) . 34
6.105 Power electronic devices (if applicable) . 34
6.106 Other components (if applicable) . 35
7 Type tests . 35
7.1 General . 35
7.1.1 Basics . 35
7.1.2 Information for identification of test objects . 36
7.1.3 Information to be included in type-test reports . 36
7.1.4 Invalid tests . 36
7.2 Dielectric tests . 36
7.2.1 General . 36
7.2.2 Ambient air conditions during tests . 36
7.2.3 Wet test procedure . 36
7.2.4 Arrangement of the equipment . 36
7.2.5 Criteria to pass the tests . 36
7.2.6 Application of the test voltage and test conditions . 36
7.2.7 Tests of switchgear and controlgear . 36
7.2.8 Artificial pollution tests for outdoor insulators . 37
7.2.9 Partial discharge tests . 37
7.2.10 Dielectric tests on auxiliary and control circuits . 37
7.2.11 Voltage test as condition check . 38
7.3 Resistance measurement . 38
7.4 Continuous current tests . 38
7.5 Short-time withstand current and peak withstand current tests . 38
7.6 Verification of the protection . 38
7.7 Tightness tests . 38
7.8 Electromagnetic compatibility (EMC) tests . 38
7.9 Additional tests on auxiliary and control circuits . 38
7.10 X-radiation test for vacuum interrupters . 38
7.101 Mechanical and environmental test . 39
7.101.1 Miscellaneous provisions for mechanical and environmental tests . 39
7.101.2 Mechanical operation test at ambient air temperature . 41
7.101.3 Low and high-temperature test . 43

– 4 – IEC TS 62271-313:2025 © IEC 2025
7.102 Short-circuit making and breaking tests. 44
7.102.1 General . 44
7.102.2 Making tests . 45
7.102.3 Breaking tests.
...