Wiring a Two Pole Breaker For a Generator

How do I wire a 20amp 2 pole breaker in my panel to be used for a generator connection? Feeding back into the panel.

Mike from FL

Answers:

Wiring a Two Pole Breaker For a Generator

(sent by email, we forward electrical requests to Dear Webby because he has a lot of knowledge about electrical stuff.)

Hi Mike,

There is a lot more to that than just wiring in a breaker.
You need an interlocking disconnect, that will totally disconnect the house from the electrical company.
Otherwise your little generator will try to power the entire neighborhood, all the way to where the line is down, and it will shock and electrocute workers trying to fix the downed line. It can also destroy your generator, when the power comes back on.

It CAN be done, and I have done it when I went to visit a friend during hurricane Wilma, but you have to keep in mind that the disconnect from the electrical company is the most important part of it.

2 pole breakers are for 220 Volt appliances.
If you have an extension cord with a 220 Volt plug on the generator side, you can bring the other end of it into the breaker panel, remove the female plug, and hang it with some dental floss or twine from the main breaker in such a way, that the wires will be above, but not quite reach the Air Conditioning breaker,

when the main breaker is on. Cap the bare ends of the black and white (or black and red) wires, and connect the green wire to ground.

When the power does go out:

• you turn the main breaker off
• undo the Air Conditioning wires from the breaker
• move the caps from the generator wires to the Air Conditioning wires
• connect the black and red wire from the 220 Volt Generator cord into the AC breaker
• turn the generator on

Naturally, you can also use a ready made interlocking disconnect switch panel, but that can be nearly as expensive as your generator.

Using this method, you only have to get two Marrettes to cap the unused wires, and a piece of dental floss or string. That string is your interlock, since it forces you to keep the main breaker off when using the cable from the generator.

If you have two outside plug-ins on different breakers, as they should be, you can use them to bring the power to the panel, instead of dragging a 220 Volt cable in from the outside and through the house to the panel. If you are interested in that method, write me directly at dearwebby @ webby.com, since it will take more space than we can reasonably expect Thrifty-Fun to dedicate to one question.

I also have a method for connecting single outlet 110 Volt generators, so that they power both polarities in your panel.

Even though this unconventional method is quite safe and works well, it seems to be unknown in Florida and your local electricians will freak out the first time they see it.

Have FUN!
DearWebby
http://webby.com/humor/
(02/19/2008)

By ThriftyFun