Automatic switching (or manual switching) between the common power supply (I) and the standby power supply (II) can be implemented to ensure the continuity, reliability, and safety of the power supply when the power supply is disconnected or abnormal (loss of voltage, phase). The current capacity is 16~3200A. The electric operating mechanism is the motor (single-phase AC). The positive and reverse rotation of the motor is used to drive the opening and closing of the power supply.