What You Should Know About Your Home’s Electrical System

You flip a switch on the wall and your lights go on, adjust a setting on the thermostat and the air conditioner starts cranking, poke a button on the dishwasher and it starts cycling through to clean the dinner dishes. It might seem like magic if you didn’t know better. But what do you really know about electricity and how it arrives and works in your home?

No matter whether your power company generates its energy from turbines fueled by flowing water, steam, combustion gases, wind, or the sun, it transforms it into electricity and sends it out via a vast network of switches, transformers, and high voltage wires strung on poles or running underground all the way to a point of connection at your house.  

This is where electrical power enters your house. The panel is housed in a large, flat metal box and is usually on an exterior back or side wall or in your basement or garage. This main breaker panel (you may be used to calling it a fuse box) distributes electricity throughout your home on a series of separate circuits.

Each circuit flows out separately on one wire and returns by another one. If the flow ever begins to reach a dangerous level, the breaker or fuse will automatically interrupt the current. If you need to, you can switch off the current manually as well.

A main circuit breaker that can shut off electricity to most or all of the circuits can be found in the panel or, less frequently, near the meter.

Circuits from the main panel bring the power to whole rooms or specific areas or appliances within them. Most large appliances are required by code to have their own dedicated circuits, some requiring two joined breakers in order to provide 240 volts as opposed to the 120 volts used by most other applications.

Older houses sometimes have a jumble of circuitry that seems to make little sense, say with baseboard outlets in one room and wall switches in an adjacent room connected on one circuit. 

That’s why it’s important to spend some time figuring out which breaker or fuse is responsible for which connection, and labeling them on your main panel so you can access them quickly if you need to.

A switch is the means by which the power of a circuit’s “hot” wire is turned on or off to a light or an appliance. Sometimes two or more switches can control the same light, for example, one on the wall and one at the baseboard; they do this by one switch passing along the “hotness” to the other.

Other kinds of switches you may have in your home include dimmers, motion sensors, photocells, timed switches, thermostats, and “smart home” switches that can be controlled by your phone or computer.

Your electric meter is located on the outside of your house somewhere between the power line from the pole and your main panel to keep track of the amount of electricity your household is using. The usage is recorded in kilowatt hours, the equivalent of how much electricity it takes to run a 100 watt lightbulb for ten hours.

A traditional analog meter has dials that are read from left to right to give you the kilowatt number, and it resets at the start of every billing period. A digital dial does not reset, so to keep track of your usage you need to note the usage each month and subtract the previous month’s reading from it.

If the numbers on your meter haven’t changed, or if it’s running very fast, contact your power company for troubleshooting.

According to the Electricity Safety Foundation International, electrical malfunctions cause more than 50,000 preventable house fires every year. An American Home Shield home warranty plan can cover service calls as well as repair and replacement of faulty elements in your system including wiring and lighting fixtures.

These conditions require the immediate attention of an electrician:

• Strange odors coming from your main panel or an electrical outlet.
• Warm or sparking outlets and switches.
• Hot ceiling fixtures.
• Buzzing, cracking or sizzling sounds when you flip a switch or plug into an outlet.

In addition, beware of counterfeit products. Buy extension cords, power strips and similar electrical products only from reputable dealers and make sure they have the Underwriters Laboratory (UL) seal.