It is mainly used to realize automatic switching between the mains power supply and the standby power supply (such as the generator set ). This device can automatically switch the load to the backup power supply when the main power supply (mains) fails or is interrupted, ensuring the continuous power supply of important loads. When the main power supply returns to normal, the ATS cabinet automatically switches the load back to the main power supply to realize the quick recovery and unattended function of the power supply system.