Automatic Transfer Switch
A Load Transfer Panel is a panel that is wired into the premises electrical distribution system to allow a generator to be used. It prevents the generator from back feeding into the mains power supply which could cause serious injury to line workers trying to restore utility power supplies.
Constant mains electricity is supplied into premises via electrical cabling. When this mains electricity is disrupted due to power failures, a signal is sent from the transfer switch to the generating set which then starts up and sends generated electricity back into the premises. When the mains supply is restored the transfer switch blocks the power from the generating set and reverts back to the main supply.