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IEC 60934
Edition 4.0 2019-01
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Circuit-breakers for equipment (CBE)
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IEC 60934
Edition 4.0 2019-01
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Circuit-breakers for equipment (CBE)
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.120.40; 29.120.50 ISBN 978-2-8322-6549-9
– 2 – IEC 60934:2019 RLV © IEC 2019
CONTENTS
FOREWORD . 8
1 Scope and object . 10
2 Normative references . 10
3 Terms and definitions . 13
3.1 Definitions related to protection and switching devices . 13
3.2 General terms . 15
3.3 Definitions related to current . 16
3.4 Definitions related to voltage . 17
3.5 Definitions related to constructional elements of a CBE . 18
3.6 Definitions related to releases in CBEs . 20
3.7 Definitions related to insulation coordination and clearances in a CBE . 21
3.8 Definitions related to operation of CBEs . 23
3.9 Definitions related to the operating characteristic of CBEs . 25
3.10 Definitions related to characteristic quantities . 25
3.11 Definitions concerning coordination of CBEs and SCPDs associated in the
same circuit . 26
3.12 Definitions related to terminals and terminations . 27
3.13 Definitions related to tests . 30
4 Classification . 30
4.1 General . 30
4.2 Quantity of poles . 30
4.3 Method of mounting . 30
4.4 Method of connection . 31
4.5 Method of operation . 31
4.6 Mode of tripping . 31
4.6.1 CBEs tripping by current (overcurrent) . 31
4.6.2 CBEs tripping by by overcurrent and voltage . 31
CBE-switch .
4.7 Influence of the ambient temperature . 31
4.8 Trip-free behaviour . 32
4.9 Influence of the mounting position . 32
4.10 Electrical performance . 32
4.11 Suitability for isolation . 32
5 Characteristics of CBEs . 32
5.1 List of characteristics . 32
5.2 Rated quantities . 33
5.2.1 General . 33
5.2.2 Rated voltages . 33
5.2.3 Rated current (I ) . 33
n
5.2.4 Rated frequency . 34
5.2.5 Rated switching capacity (rated making and breaking capacity) . 34
5.2.6 Rated conditional short-circuit current (I ) . 34
nc
5.2.7 Rated short-circuit capacity (I ) . 34
cn
5.3 Standard and preferred values . 34
5.3.1 Preferred values of rated voltage . 34
5.3.2 Standard rated frequencies . 35
5.3.3 Standard values of rated conditional short-circuit current . 35
6 Marking and other product information . 35
7 Standard conditions for operation in service . 36
7.1 General . 36
7.2 Ambient air temperature . 36
7.2.1 Reference ambient air temperature T for calibration . 36
7.2.2 Limits of ambient air temperature for operation in service . 37
7.3 Altitude . 37
7.4 Atmospheric conditions . 37
8 Requirements for construction and operation . 37
8.1 Mechanical design . 37
8.1.1 General . 37
8.1.2 Mechanism . 37
8.1.3 Clearances and creepage distances (see Annex B) . 38
8.1.4 Screws, current-carrying parts and connections . 43
8.1.5 Screw-type and screwless terminals . 43
8.1.6 Solder terminations . 47
8.1.7 Flat quick-connect male tabs (Figures E.6 to E.13) . 47
8.2 Protection against electric shock . 50
8.3 Temperature-rise . 50
8.3.1 Temperature-rise limits . 50
8.3.2 Ambient air temperature . 51
8.4 Dielectric properties . 51
8.4.1 Dielectric strength at power frequency . 51
8.4.2 Clearances for insulation coordination . 51
8.5 Conditions for automatic operation . 52
8.5.1 Standard time-current zone . 52
8.5.2 Tripping characteristic . 52
8.5.3 Operating limits of overvoltage releases . 53
8.5.4 Operating limits of undervoltage and zero-voltage releases . 53
8.5.5 Electrical endurance of undervoltage releases . 53
8.6 Electrical performance and behaviour at rated short-circuit capacity . 54
8.7 Performance under conditional short-circuit current conditions . 54
8.8 Resistance to mechanical shock and impact . 54
8.9 Resistance to heat . 54
8.10 Resistance to abnormal heat and to fire . 54
8.11 Resistance to tracking . 54
8.12 Resistance to rusting . 54
9 Tests . 58
9.1 Type tests and sequences . 58
9.2 Test conditions . 59
9.3 Test of indelibility of marking . 60
9.4 Test of reliability of terminals, current-carrying parts and connections . 60
9.4.1 Screw type and screwless terminals . 60
9.4.2 Solder terminations . 62
9.4.3 Flat quick-connect male tabs . 62
9.5 Test of reliability of terminals for external conductors (see 3.12.15) . 63
9.6 Test of protection against electric shock . 64
– 4 – IEC 60934:2019 RLV © IEC 2019
9.7 Test of dielectric properties . 65
9.7.1 Resistance to humidity . 65
9.7.2 Insulation resistance of the main circuit . 65
9.7.3 Dielectric strength of the main circuit . 66
9.7.4 Dielectric strength of the auxiliary circuits .
...