Free wiring diagram for breaker box

This free wiring diagram shows a basic circuit breaker box with breakers. This wiring diagram shows how the electrical circuits are wired and grounded for house wiring. You will see how some types of cable will have a red wire, a black wire and a white wire. This is Romex 3 wire cable made for 240-volt applications as you can see below.

Some appliances need two 120-volt lines to run. That’s why the heavier cable will use both a black wire and a red wire as hot lines. The white wires will be neutral as usual. Both the red and black will attach to the breaker which is extra wide to cover two hot bus bars in the breaker box.

The big 1/0 gauge cables that come from the meter are Aluminum cables that resist heat really well. Two cables will connect to the hot bus bars and one cable will connect down to the neutral bus bar.

free wiring diagram

This wiring diagram shows a basic breaker box with breakers.

That bus bar will be grounded by a 6-gauge copper wire that goes back outside and connects to a copper grounding rod that’s driven into the ground. The rod is four feet long and if you’re hammering it into rocks, it’s kind of tough.

The picture of the breaker box shows different sizes of breaker fuses. The narrow breakers cover only one hot bus giving it 120-volts. The wide breakers cover two hot bus bars giving them 240-volts. That’s how the voltage differences work.

The amperage ratings of the breakers is a different kind of thing that works on current or Electric flow. They trip if there is over-current in the case of a short circuit.

Over 4 million visitors to this site since it was born!

My newsletter keeps you up to date on home construction and design ideas.

home construction

I just wanted to say that I love your website. My husband and I followed your instructions on building our own home. Most of the work we did ourselves, but not all. We saved $90,000 in labor costs and now have a beautiful home that we own.

--Sue and Les Carrigan, Draper, Utah

I built my own home doing all my own labor. My house costs me around $70,000 for materials. It took me 8 months to build and is about 2,000 square feet. I didn't think I could do it, but your house web site encouraged me. I used all the info you had.

Thank you,

Benny Luis Lopez,

Gainsville, Florida

I can't thank you enough for your free information web site about home building. I was looking for Electrical wiring diagrams when I found your site. It was very helpful.

Steve Lundquist,

Little Rock, Arkansas

My wife and I lost our home to foreclosure but we kept a plot of land to start over. We are halfway through the construction of our house. Your website gave us hope to start over and build a house with low payments. We are in our late 60's but we find it rewarding to put so much effort into a project that will reward us for years to come.

Name respectfully withheld