How to Wire a Generator to a Breaker Box All by Yourself!

It’s quite complicating whenever you need to deal with your home electric box and sometimes there’s no other way but to manipulate it for better using. I’ve been asked numerous times about how to hook up generator to breaker box.

This is not a new thing and most homeowners can easily pull off this simple task with basic electric handling knowledge. The overall wire generator to breaker box, of course, needs you to be extra careful and completely acknowledged about what you’re doing.

How to Wire A Generator to A Breaker Box All by Yourself

Hook Up Generator to Breaker Box

So today, I’ll be answering a very common question in my article, which is how to wire generator into breaker box. Keep reading till the end!

Understand Wiring Concept!

Suppose, you have a 240-volt circuit. Now this will come with a couple of wires that together work as 240 volts. Each of these wires individually carries 120 volts. There should be a green or copper-colored wire that is known as ground.

When you are dealing with a 240-volt circuit, there is no neutral wire to use. You may want to use a 240-volt circuit for both 120-volt & 240-volt application.

If you own a generator with 240-volt connection, simply wire it directly. You should do so with only 240-volt capabilities.

A generator is an extra power source or backup, we all already know that. You should keep the wiring dedicated to generator’s need. This is because it will be used for extra or emergency power needs.

Materials You’ll Need

To connect a generator to breaker box, you’ll need a few materials. These are:

  • Double pole breaker with 40-amp power
  • Stripper Tool.
  • Eight-by-three cable.
  • Screwdriver (with flathead).
  • Voltmeter.

Stop Every Connection

The main power source of your house needs to be turned off. You should use a voltmeter to check. See if the termination if electricity into breaker panel is rightly done. If the electricity still shows flowing, you should not start working until it stops.


You need to use an eight-by-three cable for this step. Expose the end of the wire for about half inch. You can try using a stripper tool to make a cleaner cut and expose it. Make sure you strip the ends by half-inch, each of them.

Screwing Wires

Get the two black wires and gradually screw them to a circuit breaker. There should be two screws inside the circuit breaker. These are meant to hold both wires appropriately. Use the wires and insert in fully into terminals. Now tighten screws securely and make sure they don’t come out.

Breaker to Service Panel

It’s time to fix the breaker inside the service panel. Find a spot where you want the circuit to reside. Now simply set breaker inside the housing of service panel at that spot. Use back and forth rocking motion for the circuit.

This way you’ll be able to put the tabbed end of the breaker at housing first. Now over the hot bus bar, simply snap rest of breaker to finish installing.

Check Double Pole Breaker

You need to have a look at the double pole breaker. Make sure it fits tightly. Double pole breaker is basically suitable for 240-volt installation. It comes with two 120-volt hot wires summing up to 240 volts.


Now the wire for ground needs to run through similar bar. It should run till the end of 240-volt receptacle inside breaker box. After inserting ground wire to the end of 240-volt receptacle, tightly screw it there.

Now simply insert the eight-by-three cable to outlet of generator you want to plug it in. There should be two screws without any color. Fix the two black wires into these screws. Make sure you put the ground wire into green screw. Fix them tightly so that they stay in place.

Outlet Attaching

Once you have secured the eight-by-three cable, it is time to attach outlets to wall. Go back to the main power source of your house. You can turn it on now. Also, turn ON your breaker box with a simple push. Plug the generator into this outlet and it should start.

Important Tips

Make sure the two-line voltage wires are of same color. This will make complying with code easier. Black and red are favorable colors for this task. You can also use tapes to mark them if it is necessary.

For a forty-amp breaker, an eight-by-three cable works perfectly.

Sometimes shutting off breakers isn’t the only reason for main panel de-energizing. Always check with a voltmeter to ensure proper electricity termination. Electric shock can be a reason for your death.


Some states and areas don’t allow homeowners to manipulate electrics, even if it’s their own property. It might cause a violation and you’ll be completely responsible for that.


That’s all for the whole process of wiring a generator to breaker box. It’s not hard, pretty simple actually.

But I don’t recommend to do it yourself if you have zero to less knowledge about electrical handling. There are electricians who can do these things for a small price. Of course, if you have confidence and previous knowledge regarding electrical fixtures and so on, it’s probably the best to do it yourself. Good Luck!

1 thought on “How to Wire a Generator to a Breaker Box All by Yourself!”

  1. We can’t find anyone who can do this for us. Seems electricians around here don’t know what I’m talking about. We live in Pulaski County, Va. One man does it but he’s not licensed and he will only do it for special friends.


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