1. General selection principle
Rated operating voltage of the miniature circuit breakers ≥ line rated voltage
Rated current of the miniature circuit breaker ≥ line calculation load current
Rated short-circuit making-breaking capability of the miniature circuit-breaker ≥ The maximum short-circuit current that may appear in the line
Instantaneous release set current of the miniature circuit breaker ≤ 0.8 times line end single-phase to ground short-circuit current

2. Selection of miniature circuit breaker for wire protection
Long delay current setting value ≤ line load current
Instantaneous operation setting value ≤ (6-20) times the line calculate load current

3. Selection of miniature circuit breaker for motor protection
Long delay current setting = motor rated current
Instantaneous operation setting value = (8-15) times the motor rated current (for the protection of squirrel-cage motor) = (3-6) times the motor rated current (to protect the winding motor)

TAIXI ELECTRIC is a company specializing in the production of miniature circuit breaker, including various models, such as DZ30-32, DZ47-63, DZ47-125, DZ47S-63, DZ47S-125, TXL7-63, TXC65-63, TXB7S-63, TXB7S5-63, TXB7N-63, DZ47-B63, DZ47-B125, DZ47Z-63, TXB7Z-125 and so on.

Welcome to contact us, TAIXI ELECTRIC will serve wholeheartedly for you!