How to Install Standby Generators at Home

Standby generators can be lifesavers in an emergency. In the event of a power outage, a generator can supply power to the house for heat and electricity that will keep food from spoiling in your freezer and refrigerator. Although businesses and hospitals use standby generators, they’re also good to have at home, especially if you have young children or old people in the house.

Step 1 - What Size Generator?

The first thing to establish is the size of generator you need. You should go for a minimum of 4,200 watts. This will power the basic systems in your house. With a gasoline powered generator, you should keep it in the garage or a shed away from the house. It will be light enough that you can move it next to the house when you need to use it. Due to carbon dioxide fumes, always use gas powered standby generators outside. Follow instructions and standby generators are perfectly safe.

Step 2 - Service Panel

Start by putting the box of the new service panel on the wall close to the old service panel. You’ll need to run a length of conduit between them to accommodate the wiring. With this done, install the ground buss in the new panel by screw it in place. As you won’t be trying to run everything from the generator, you’re only concerned with specific circuits within the house. Identify these on the breaker panel

Step 3 - Circuit Breakers

Make sure the main power to the house is off. Using an insulated screwdriver, remove the three wires for the circuit then unscrew the breaker. Tape the three wires together. Rub insulated wire through the conduit, with red, white, black and green codes for each of the circuits. Make sure to connect the ground and neutral wires to the appropriate buses in the main panel. Meanwhile connect the red and black wires to a new breaker in the new box. You’ll need to repeat this for all of the circuits you want the generator to be able to run.

Extend the original circuit wires from the main box into the new box with more wires and wire connectors and hook up to the buses and the breaker. Secure the breakers in place in the new panel.

Step 4 - Outdoor Receptacle

At this point you’re read to connect up the new breaker box to the outdoor receptacle you’ll use for the standby generators. Use 10/4 cable, running out from the new box to the receptacle. Strip the wires in the box, attach the red and black to a breaker. Hot and neutral with go to the appropriate buses.

You’ll need an exterior box that’s weather tight for the outdoor receptacle. Wire it according to the instructions. You can buy an extension cord for the standby generator or out your own together. It should be at least 6 feet long. Make sure you have a flat, cleared area of ground on which you can stand the generator.

Looking to purchase a new generator? Check out our Generators Buyer's Guide.