Breaker Box Wiring: How to Do it Like a Pro

The circuit breaker is a crucial part of the electrical system in your house. Learn what each switch does and how to install the electric circuit breaker panel in this article.

Electricity is a very pivotal part of our daily lives. It helps power industries and our homes. The electrical circuit breaker panel is the link between the power from the street and the electrical appliances in your household. And because electricity wields so much energy and it is volatile, you should always consult professional electrical services when you are in doubt about electrical faults in your home.

Let's discuss the circuit breaker panel wiring, the install, its components, and how they operate.

What Is a Breaker Box in House Electrical Wiring?

The main circuit breaker panel is a big switch in the house that takes power from the electrical cables on the street and safely distributes it to all the electrical appliances in your household. The main breaker box comprises other small switches called breakers, each connected to a specific house area. You might ask, how is a circuit breaker wired? Here’s how.

Double Pole Service Disconnect

The double pole service disconnect is a double-wide breaker that takes up to two slots in the breaker box. This connector of the breaker box wiring is the first point of contact with the power from the meter. Although the wire coming is one, they snap into two when they reach the double pole breaker. Each wire carries 120 volts and a combined total of 240 volts. 

The two halves of the double pole breaker work together in that if there is a problem with one of the wires, the other half will trip and shut down the entire circuit, which in turn shuts down all the electrical appliances in your house.

Hot Bus Bars

The hot bus bars extend the hot wires from the double pole service disconnect. After each wire exits the main breaker, it enters a separate bus. The buses are metal bars that run vertically on the left and right. 

Neutral Bus

The purpose of the neutral bus bar is to receive power from the electrical gadgets in your home. After receiving the electrical current, the neutral bar returns the power to the main grid. The neutral circuit wire is usually white.

Circuit Breakers

The circuit breaker serves as a protector for the electrical circuit. The breaker panel wiring in the circuit breaker protects electrical circuits and appliances from issues such as electrical overload, short circuits, and ground faults.

The circuit breaker is essentially in two rows. They are the single pole with 15 amps and 20 amps and the double pole that ranges from 15 amps to 70 amps.

The 15 amps of the single-pole circuit power the regular lighting and outlets circuit. On the other hand, the 20 amps of the single-pole supply current to other areas like the kitchen, garage, and electrical appliances.

The double pole circuit breakers range from 15 to 70 and are used for electrical devices that run on 240 volts, like water heaters and electric dryers.

Fuse box is crucial. Learning how to wire a circuit breaker will help you during an emergency


The grounding wire in the circuit breaker is a safety wire intentionally connected to a metal water pipe in the earth. The grounding does not carry electricity under the regular operation of the circuit. Its primary purpose is to control electrical current under a short circuit or during other dangerous conditions in an electrical panel wiring.

How to Wire a Breaker Box Like a Professional

Wiring a circuit breaker panel can be dangerous. Homeowners should remember not to temper them if they have the option to turn to trained electricians.


Before laying down the wires for the fuse box installation, the most crucial step is to plan where to place the container. Then, you should gather all the necessary equipment in one place. You must have a residential breaker box diagram to help expedite the wiring process.

How to Run Cables to Electrical Boxes

Select the cables that can handle the electrical load of the new circuit. Some electrical phase outlets will need a 15 amps circuit, while others require a 20 amps circuit.

  • Run the cables between electrical boxes
  • Here’s how to wire a room to a circuit breaker phase. Add fish tape to run cables behind the walls
  • Run the cables from each electric box to the circuit breaker panel. Don’t wire the breaker immediately.
  • At each electric box, connect the wire to its appropriate switch according to the circuit plan.

Wiring the New Circuit Breaker

Here is how to wire a circuit breaker:

  • Use a wire stripper to remove a ½ inch insulation from the neutral wire.
  • Insert the open part of the neutral wire into the neutral bus bar and tighten it with a screw.
  • Insert the stripped end of the hot wire into the terminal and tighten it. When installing a 120/240-volt circuit, connect the red-hot wire to the second circuit breaker terminal.
  • To install the circuit breaker into the panel, place the breaker where your wire will terminate into the notch away from the bus bars.
  • Place the extra neutral and hot wires inside the panel.

The steps are similar when installing only 240-volt circuits. Just follow the steps above. The only difference is that the 240-volts circuit breaker has no neutral wire.

How to Replace the Panel Cover

  • Use a pair of pliers to remove the breaker knockout on the panel cover.
  • Replace the panel cover and tighten the screws.
  • Switch off the individual circuit breakers before switching on the main breaker.
  • Switch on the main breaker, then switch on the individual circuit breakers.
  • For easy identification, label the new circuit breaker on the breaker panel cover.
  • Test each switch or appliance to see if the installation was successful.

How is a circuit breaker wired? By connecting a double-pole breaker, neutral bus bar, and grounding

Hire an Expert Electrician for Your Breaker Box Wiring

McCarrick Electric is a generational family company founded in the 60s. We've been providing electrical services, including electrical circuit breaker panel wiring, to ensure safety and consistent power flow to the households in Colorado ever since then. Our electricians have a combined experience of 25+ years.

We take pride in our customers and their needs. We go far and beyond to deliver exceptional electrical installations. 

If you need help with electrical panel installation, you can find McCarrick Electric at 10843 E. 96TH PL. Commerce City, CO 80022. We provide electrical services in and around these areas:

  • Aurora
  • Denver
  • Henderson
  • Brighton
  • Thornton
  • Westminster
  • Highlands Ranch
  • Littleton
  • Parker

We are the company you need when looking for trustworthy breaker box wiring installers. While working, we ensure the safety of everyone in the house. Whether you need electric panel installation or electrical switches installation, we have the expertise and experience to do it. Call us today for a quote.

720-601-1991 Contact Us