You are preparing a festive holiday meal. Or you’re watching the big game. Or you’re drying your hair, getting ready for work or an evening out. Suddenly, the oven stops working. Or the TV flickers off. Or the hair dryer stops.

You’ve tripped a circuit breaker (if you have a fuse box, click here).

Circuit breakers “trip” (interrupt the flow of electricity) to prevent a circuit overload or fire due to a short circuit. Breakers are designed to trip at a specific number of amps, such as 15, 20 or 30.

Circuit breakers are found in circuit breaker boxes, and are generally organized in vertical or horizontal rows. Circuit breaker boxes are frequently in the basement, but could also be in a stairwell, closet or even the garage. You should always know where your circuit breaker box is. You should also always have a flashlight near the box. If the tripped breaker is the one that controls the electricity near the box, you will need the flashlight to see.

A circuit breaker is a UL rated safety device that looks like a small light switch.   Each breaker connects to a specific area of your home. The most common breakers are 110 volts. Large appliances such as kitchen ranges, dryers, and air conditioners may connect to larger breakers that require 220 volts of electricity. You should label each breaker so you know what it connects to. You should also write down on a piece of paper or on your computer how the breakers are configured.

When a breaker is tripped, the switch moves from the on position to a middle position but rarely to the completely off position. For example, if the on position is left, the switch will move slightly to the right. Sometimes you have to look closely to determine which breaker has tripped. Just run your hand along the row of breakers and locate the one that is out of line. To reset the breaker, move the switch all the way to the off position and then turn it back on.

If the breaker continues to trip, it may mean too many items are plugged into the same circuit. This is increasingly common, especially in older homes that were not wired to handle today’s demand for electricity. One hint: the use of cube taps and power strips that increase the number of devices we can plug into one outlet. If this is the case, try disconnecting some of the items.

If this does not solve the problem, something plugged into that circuit may be shorted out. Try unplugging everything from that circuit. If the circuit continues to trip, you may have a bigger issue that requires rewiring existing circuits and/or adding additional circuits. Unless you really, really know what you are doing, you should hire a qualified electrical contractor to do this.