A home electrical system is the wiring in a house, the electrical service panel where electricity enters the house, and every electrical switch, electrical receptacle, and other device that allows use of the electrical power provided. The electrical system supplies power for lighting, heating, and operation of electrical equipment and appliances. When it doesn't work, chances are that you can fix it!

Components of a typical residential electrical system.

How Does It Work?

How does electricity do its job? Electrical current flows to the electrical device through a hot (usually black) wire. The current flows back to its source over the neutral or ground wire. Current is the flow of electrons in a wire, measured in amperes or amps. Volts are the pressure that moves the electrons along the wires. Ohms measure the resistance to the flow of an electric current.

Power for most homes comes from a regional power company. Wires bring the electricity to an electrical meter where household usage is measured, then to the electrical service panel, which distributes the power to individual circuits. Household circuits are either 120-volt or 240-volt. The 120-volt circuits power most of a home from lighting to blenders to refrigerators. A few large appliances, such as electric kitchen stoves, dryers, central air conditioners, and water heaters run on 240-volt circuits.

Caution!

Turn off power before working on any electrical system.

What Can Go Wrong?

The power source coming into your home can fail. Wires within your home can short out or fail. Circuit breakers can trip and fuses can burn out. Electrical receptacles and electrical switches can malfunction.

Fix-It Tip

Be sure any light, appliance, switch, receptacle, or other electrical device you use has an approval label by Underwriters Laboratory. The label means the device meets safety standards.