How to Test a Circuit Breaker
- 1). Open the electrical box in your home. You should see a long row of black switches corresponding to a different part of your house. (Ideally, they will be labeled as such so you can tell which one goes to which part of the house.) These are the circuit breakers.
- 2). Turn off or unplug all electronic devices being powered through the questionable circuit breaker. This will prevent a short in case there's any kind of unforeseen surge.
- 3). Check the pertinent circuit breaker to see if it's in the "off" position. If it is, it's likely doing its job (though you should still complete the test to make sure). Turn the circuit to the "on" position. If it trips back to the off position within a few seconds, then the problem is probably with the wiring itself, and will require the attention of a professional electrician.
- 4). Set a multimeter to the "Volts AC" position. Touch one prong to the breaker's terminal screw and the other prong to the ground screw. Check the indicator on the multimeter. If the light doesn't go on or it doesn't indicate anything on the readout, then there's no power flowing and the circuit will need to be replaced.
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