
7
Chapter
2
CONTENTS
Operating characteristics
and performance
2-1 Overcurrent tripping characteristics
2-1-1 Types of tripping ............................................................................................................8
2-1-2 Factors affecting overcurrent trip characteristics ...........................................................8
2-2 Breaking performance
2-2-1 Short-circuit current breaking ......................................................................................11
2-2-2 Breaking characteristics ..............................................................................................12
2-2-3 Arc space ....................................................................................................................13
2-2-4 Reset time ...................................................................................................................25
2-3 Overload switching performance
.................................................................26
2-4 Performance with current at 100%
2-4-1 Temperature rise .........................................................................................................27
2-4-2 Internal resistance and power consumption ................................................................27
2-5 Durability
2-5-1 Switching durability
......................................................................................................29
2-5-2 Trip switching durability ...............................................................................................29
2-5-3 Rated ultimate short-circuit breaking performance .....................................................29
2-5-4 Switching durability of accessories ..............................................................................30
2-6 Withstand voltage performance
2-6-1 Rated power frequency withstand voltage (IEC 60947-1, 2) .......................................31
2-6-2 Rated impulse withstand voltage (IEC 60947-1, 2) .....................................................31
2-7 Handle operating force and angle
................................................................32