Dual power supply switching circuit The two circuit breakers are in the closed state. When the main power supply is cut off, the normally closed contact of the main contactor is reset, the standby contactor coil is energized, and the standby power supply supplies power. When the main power supply is energized, the main contactor is closed, the normally closed contact is disconnected, and the standby contactor coil is de-energized. . . . . . . . #powersupply #power #powerelectronics #powerenginee