How do I tell which breaker controls an outlet or switch?

Draw floor plans of your home or business and mark the location of all lights and electrical receptacles. Remember to label the garage and any outdoor areas.

This is a two-person job. Each of you should have a handheld radio so that you can communicate with one another during the task.

Steps for mapping circuit breakers in your home to outlets and switches:

• Turn on the lights in every room of your home so that your helper can more easily identify which breaker you have turned off. Remember to turn on switches that are connected to electrical outlets.
• Give your helper the floor plans, a pencil and a small appliance (such as a digital clock) to plug into receptacles to test for power.
• Open the door of your breaker box and begin with the first breaker at the top of the row. Communicate to your helper, via radio, that you are going to flip the first breaker. Ask your helper to tell you the location of the light or lights that went out. Your helper will also need to test each outlet in the room by plugging in the small appliance. Have your helper write a “1” on each light and receptacle in the plans that is connected to breaker No. 1.
• Tear off a small piece of masking tape and place it next to the breaker and write the location that is connected to the first breaker with a permanent marker. You can also write directly on the breaker box if you don’t want to use tape.
• Switch the breaker back to the “on” position. Your partner can turn out any lights in the room once they’re marked on the plans.
• Continue flipping breakers and labeling them as your helper identifies where the power has been suspended. If your helper can’t readily identify a location that’s connected to a breaker, mark the area next to the breaker with a small dot. Come back to it after you have finished identifying the rest of the circuit breakers. You can then look at the plans and figure out what location goes with the breaker in question.

Check your state and local codes before starting any project. Follow all safety precautions. Every effort has been made to ensure the accuracy and safety of this information. Neither Westlake nor any contributor can be held responsible for damages or injuries resulting from the use of the information in this document.