What is the function of a transfer switch?

A transfer switch is essential for safely managing the source of electrical power supplied to a building or structure. Its primary function is to switch between different power sources, most commonly between utility power and a backup generator. When utility power is lost, the transfer switch disconnects the building from the grid and connects it to the generator, ensuring that power can still be supplied without risk of back-feeding into the utility lines, which could create dangerous situations for utility workers and equipment.

Understanding this function highlights the importance of transfer switches in emergency preparedness and safety in electrical systems. It allows for a seamless transition of power, enabling continuous operation of essential services during power outages. This capability makes transfer switches a critical component in backup power systems.