The nominal insulation voltage of this product is 660V 50Hz AC while the rated operational voltage is 380V and below, and the rated operational voltage is 16-1250A. The breaker is normally used for power distribution. Under normal circumstances, the breaker can be used for less frequent conversion in the circuit or less frequent starting of the electric motor respectively. In a power distribution network, the breaker is used for distributing power as well as protection against overload and short circuit of the circuit and the electrical power unit. Breakers for electric motor protection use can be used for the staring, breaking during operation and overload protection and short circuit protection of squirrel cage motors