Portable generator transfer switch and interlock installation
Safely power your home from a portable generator. Get matched with a licensed Port St. Lucie area electrician for a transfer switch or interlock install.
A portable generator is a lower cost way to get through an outage, but plugging it into the house the wrong way is dangerous. A transfer switch or an interlock kit is the safe way to connect one. It lets the generator feed your home wiring without running cords through windows.
Why you cannot backfeed
Some people plug a generator into a dryer outlet with a homemade cord. That sends power back out through the house and onto the street. It can electrocute a lineworker who thinks the line is dead, and it can start a fire in your own wiring. It is also illegal in many places. Do not do it.
Two safe options
Manual transfer switch. A small separate panel is wired next to your main panel. You pick a set of circuits, such as the refrigerator, some lights and the internet, and the switch moves them from utility power to the generator. It cannot backfeed.
Interlock kit. A mechanical plate on your main panel stops the main breaker and the generator breaker from being on at the same time. It often costs less than a transfer switch, and it lets you power more of the house, but you have to manage the load yourself so you do not overload the generator. It also needs a power inlet box on the outside wall.
What you need
- A generator with enough output for the circuits you want
- An outdoor power inlet, which is the plug where the generator cord connects
- A proper cord rated for the load
- A transfer switch or interlock approved for your panel
Permits and licensing
This is electrical work. It needs a permit from your city or county and should be done by a licensed electrical contractor. An inspector checks the work. Not every panel accepts an interlock, so a contractor checks that the kit matches your brand and model.
Where to run the generator
Always run it outside, well away from doors, windows and vents. Carbon monoxide kills people every storm season. A garage is not far enough away, even with the door open.
What it costs
Cost depends on the type, the panel, the distance from the panel to the inlet box, and permit fees. It is usually well below a full standby install. If you later want an automatic unit, see standby generator installation.