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What is a Circuit Breaker Panel?

Panels and Distribution

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Circuit Breaker Panel

Circuit Breaker Panel

Photo: Timothy Thiele

What is a Circuit Breaker Panel and How is it Fed?

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 in to 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.

What are Phases?

You’ll notice that there are two rows of buss running up and down. These are the two phases of electrical power that you’ll be connecting the branch circuit breakers to. The utility company provides single-phase power to most homes. They are “A” and “B” phases. The top connection point is “A” phase and the next breaker down is “B” phase. They stagger the rest of the way down the buss.

To make it easier for you to understand, circuits 1, 5, 9, etc. and 2, 6, 10, etc. are “A” phase. Circuits 3, 7, 11, etc. and 4, 8, 12, etc. are “B” phase.

What is the Minimum Sized Panel Required and Why?

A 100-amp service is the minimum size service required for a new home. In older homes, many were equipped with 60-amp services and some, believe it or not, only had “A” phase feeding the entire house. Of course that was years ago before the age of automation.

Today we have microwaves, coffee pots, can openers, crock pots, toasters, waffle irons, pizza ovens, dish washers, air conditioners, hot tubs, air compressors, and many other things that draw an enormous amount of power.

I guess the older crowd would call us the lazy society because we have tools to do all of our work for us. With these modern conveniences, there is the ever-increasing need for, as Tim “The Tool Man Taylor” would say, MORE POWER!

What Size Panel Does My Home Need?

In a standard-sized home equipped with three or less major appliances, a 100-amp circuit breaker panel will provide an adequate amount of power to feed the home. If you have a much larger home with many more appliances, a good choice would be to install a 200-amp circuit breaker panel.

If you are unsure what size you will need, you can calculate by looking at the name plate rating of each of the appliances you intend to install. If you are still unsure, call a professional electrician in to help you estimate the load requirements for your home.

How to Install Breakers and How They Work?

Breakers are installed in the slot brackets provided. To install, simply press the back side of the breaker into the bracket, this is closest to the side of the panel. Then press firmly the front side of the breaker onto the buss bar. This will be the side of the breaker where the switch is located.

Looking at the face of the breaker, you’ll notice the switch and a clear sight. The switch turns on and off and the sight shows a color, usually red, when the breaker is in the tripped state. A tripped state is when the circuit has a short in it and the breaker turns itself off because of an overload.

How to Turn a Breaker On and Off?

To turn a breaker off, simply flip the switch to the off position. This will be away from the center towards the outer case. To turn the breaker on, flip the breaker to the on position. This will be towards the center of the panel. In order to turn back on a tripped breaker, you must first turn the breaker to the off position first and then back to the on position. This resets the breaker to a usable state.

Other Parts of a Circuit Breaker Panel

The breaker panel also comes equipped with a neutral buss and a grounding bar. The enclosure is sealed off for protection by a panel cover and is usually mounted with screws. It features a panel access door that allows you to access the breakers without removing the cover.

Inside the door is a panel index. This is where you will write down what the circuits are feeding for easy reference. The entire breaker panel is usually gray in color and is made of metal. It can either be surface mounted or installed within a wall for a neater, more hidden look.

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