The Electrical Service Size of Your Home

Main Service Circuit Breaker Sizes

main breaker panel
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Your electrical service is the power headquarters for your home. It divides the power to different parts of the home in circuitry via circuit breakers in a circuit breaker panel. To fully understand how it all works, we must first know what each of these are and how they work.

Electrical Circuit Breaker Panel

First, an electrical circuit breaker panel is the main distribution point for electrical circuits in your home.

It usually provides between 100 and 200 amps of power to your home, depending on your home’s load demand. Power comes into your home from the utility company, through a service entrance. It flows through an electrical meter, through an electrical disconnect and then to the main breaker in your electrical panel.

The main breaker is located at the top or bottom of two rows of breakers, depending which way the panel is mounted. The main breaker is marked with the value of protection (like 100 amps) on the breaker handle. This breaker is either factory mounted or can be added by either bolting it in or snapping it into place. The main circuit breaker in your home dictates how much power your home can use. This breaker is located in the main service panel of your home. You home is either equipped with a fuse panel or a circuit breaker panel.

The Main Breaker

So, what is a main breaker anyway? You'd think that it is something special having a name like that.

Actually, the main breaker is the breaker that the feeder wire connects to. This breaker is a two-pole breaker that is connected to 240 volts to power your home. The main breaker acts as the disconnecting means to the entire power load of your breaker box. With it off, there is no power being fed to the buss bar that feeds the branch circuit breakers.

Your electrical panel is full of circuit breakers, running from top to bottom of the service panel. The odd numbered breakers are located on the left and the even numbered circuit breakers are on the right. Atop the many circuit breakers is a larger circuit breaker that is used to turn the entire circuit breaker panel on or off. It is known as the main breaker. It plays probably the most important function in the whole circuit breaker panel. It is a means of disconnect for the entire panel. But you may ask what makes it different from the rest of the circuit breakers within the panel.

How Power Enters Your Home

An electrical circuit breaker panel is the main distribution point for electrical circuits in your home. It usually provides between 100 and 200 amps of power to your home, depending on your home’s load demand. Power comes into your home from the utility company, through a service entrance. It flows through an electrical meter, through an electrical disconnect and then to the main breaker in your electrical panel.

The main breaker is located at the top or bottom of two rows of breakers, depending which way the panel is mounted. The main breaker is marked with the value of protection (like 100 amps) on the breaker handle.

This breaker is either factory mounted or can be added by either bolting it in or snapping it into place.

Where Main Circuit Breaker Is Located

The circuit breaker panel has a main breaker to disconnect power to the entire electrical buss bar and its branch circuit breakers. Normally, the main breaker is located on the top of the buss, but sometimes the panel is installed upside down for a bottom feed breaker position.

The main circuit breaker has the amperage listed on the handle. Most generally, the main service size will be 100 or 200 amps. It is possible that a larger service is needed in larger homes and those with extensive electrical loads. Homes that have a 60-amp service or less may be needing an update.

Older service panels, of the fuse type, use cartrige fuses as the main disconnecting means instead of the circuit breakers to disconnect the power.

They normally have the main discconnect and a range feed protected with cartirge fuses and four screw-in fuses that provide the branch circuits with protection. These panels are outdated because of the large demand for power that we all seem to have.