If a circuit is overloaded or it shorts, the breaker will trip and cut off electricity to prevent fire and/or electrocution. Follow these steps to turn the power back on.
Instructions
Turn off the light switches and unplug appliances in the room that has lost power.
Find your circuit breaker box and open the cover.
Locate the tripped breaker. Circuit breakers are small, usually horizontal switches labeled by the areas of the house they serve (for example, "kitchen," "bathroom" and so on). The tripped circuit breaker will be in the "off" position or in a middle position between "on" and "off."
Reset the breaker by moving it to the full "off" position and then back to "on." That may clear an overload and return power to the room. If the breaker re-trips, you may have too many lamps and appliances plugged into the circuit; a damaged cord or plug; a short circuit in a receptacle, switch or fixture; or faulty wiring.
Identify and correct the malfunction before resetting the breaker.

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