Understanding Your Home's Electrical Service Size

Understanding your home’s electrical panel box is a necessary first step towards properly sizing your standby generator and transfer switch.

Electricity provided by the utility company will pass through a meter on or near your home and then likely be routed to your home’s electrical panel. The panel will contain one large main circuit breaker that will feed electricity to the other circuit breakers in your panel box. The main circuit breaker’s rated amperage is referred to as the size of electrical service powering the home. The size of the main breaker can range from 50 to 400 Amperes, but most homes are either 100 or 200 Amperes. If you open the access door on your panel box the main breaker could be located at the top, bottom, or middle of your panel. The amperage rating will be printed on the circuit breaker. It will be important to identify this value as it will be needed to select the appropriate transfer switch.