Why Understanding Your System is Important

Your power company takes care of getting power to your home, but once it enters your home, everything related to your home’s electrical system — wiring, switches, outlets, fixtures — is your responsibility. As a homeowner, it’s important to know enough about the basic components of your system to make smart decisions about safety, maintenance, and upgrades.  

• Safety. Over 6% of home fires are caused by electrical issues. That’s a significant number. Knowing the basics of how electricity works in your home may prevent an unnecessary electrical fire.
• Maintenance. An electrical problem in your home may not be quite as obvious as a leaky faucet. Regular evaluation and maintenance of your home’s electrical basics may prevent problems from developing. 
• Upgrades. Do you want to add more outlets, new switches, or smart features to your home’s electrical system? How about adding a standby generator or other device? Understanding your home’s electrical basics can help you make informed decisions.  

System Connection and the Electric Meter

Unless you’re partly or wholly off the grid, your electricity comes to you via your electric company’s mains. The mains can be above-ground or buried underground. But before you can use the electricity in your home, the power company needs to know how much power you’re using. That’s the job of the electric meter, which is located between the mains and your home and measures the amount of power that your home consumes. There are three types of electrical meters. 

• Electromechanical – If your electric meter has a series of dials and a spinning disc behind a glass cover, you’ve got an electromechanical meter. While the technology for these is pretty old school, they are still fairly common.  Usually, a power company employee must manually read the meter so they know how much power your home has used. 
• Smart meters – These electronic meters can communicate directly with the power company, allowing more accurate tracking of when and how much power you’re using. These units have digital displays and can be read remotely.
• Bi-directional meters – Most electric meters only measure the power you consume. If you produce your own power, via solar panels or some other source, you may be able to sell the excess power you produce back to the power company. Bi-directional meters measure both the power coming in, and the power you’re sending out. 

It’s important to know that you don’t own the electric meter. It’s the responsibility of the utility to install and maintain the meter. If you ever have questions or concerns about your meter, contact your electricity provider. 

Disconnect Switch

Your home may have a disconnect switch located near the electric meter. Throwing this switch will cut off all power to your home. That’s useful in the event of an emergency or if major work is being done on the electrical system. If your home doesn’t have this switch, don’t worry. You can still cut off all the power at the main service panel.

Breaker Panel

Once past the electric meter, electricity must be distributed throughout your home to the switches, outlets, appliances, and other devices that need power. Your breaker panel is where the process begins. The service panel is known by many names: breaker panel, breaker box, service panel, and distribution panel are some of the common ones. If you have an older home you may have a fuse box that performs the same function. 

Main circuit breakerThe power line entering your home first passes through the main circuit breaker. This switch controls the flow of power to the branch circuit breakers also located in the service panel. By flipping this switch to OFF, you can cut all power to your home. 

Branch circuit breakersPower is routed from the main circuit breaker to branch circuit breakers. Each of these switches controls the flow of power to a portion of your home, and if they detect too much current flowing through them they’ll shut off, or “trip.” For example, one branch circuit breaker may control power flowing to your kitchen outlets and lighting, while another controls power to an electric range. Branch circuit breakers are “single-pole” or “double-pole.” Single-pole breakers control the flow of 125-volt current used by wall outlets, lights, and so on, while double-pole breakers control the flow of 250-volt current used by dryers, electric ranges, electric-vehicle chargers, and other appliances. Circuit breakers are rated by amperage. A higher number means that the circuit can handle a higher electric load. Most household 125-volt circuits are rated at around 30 amps. 

Sub-panelsSome homes will have sub-panels connected to the main breaker panel. These are smaller service panels containing fewer breakers. They’re often used when an addition or outbuilding has been added to the home, or when a backup generator is wired into the home’s electrical system. 

Interested in learning more about your home’s circuit breaker panel? Check out this guide.