Selection Of General Low Voltage Circuit Breaker

There are five main points in the selection of low voltage circuit breaker

(1) The rated voltage of low voltage circuit breaker shall not be less than that of line

(2) The rated current of the low voltage circuit breaker shall not be less than the calculated load current of the line

(3) The limit breaking capacity of low voltage circuit breaker is not less than the maximum short circuit current in the line

(4) Single phase to ground short circuit current at the end of line △ instantaneous (or short delay) tripping setting current of low voltage circuit breaker ≥ 1.25

(5) The rated current of the release shall not be less than the calculated current of the line

(6) The rated voltage of the under voltage release is equal to the rated voltage of the line