Why You Need a Transfer Switch

While it’s possible to use a portable generator without a manual transfer switch during a power outage, transfer switches make it easier to power lights and appliances throughout your home. Without a transfer switch, you’re limited to powering items that can be plugged into an outlet. A transfer switch lets you safely power hard-wired items such as your furnace, water heater, or well pump, as well as lights and appliances such as a refrigerator and sump pump.

Another safety feature of a transfer switch is that it isolates the selected circuits from the main grid. Back feed, which is when electricity goes down power lines in an inverse direction, never happens with a transfer switch. Back feed is dangerous and can lead to a fire. It can also cause anyone working on the power grid to be electrocuted. 

What is a Manual Transfer Switch and How Does It Work?

A manual transfer switch is a device that is wired directly into your home’s electrical panel. It allows you to safely choose your home’s source of electric power—either the utility source or your portable generator. Once you turn your portable generator on, you connect its output to the input of the manual transfer switch. Then you manually switch from utility to portable generator power. When utility power returns, you reverse the process.

Installing a transfer switch is relatively straightforward, but requires a professional electrician. Because many portable generators are not powerful enough to back up your entire home, you will need to tell your electrician which rooms and/or appliances you want to power with your generator. The electrician will then wire the transfer switch so that only those circuits you identified will be powered by the generator.