How to Wire a Single-Pole Ground-Fault Circuit Breaker
- 1). Inspect the area around the circuit breaker panel. For panels located in a damp area place the rubber mat on the damp floor for safety. Damp floors are good electrical conductors. Remove the panel's outer cover/trim. Remove the inner panel covering the circuit breakers.
- 2). Turn off the circuit breaker that you are switching out. Check, using the DMM or noncontact voltage tester, to be sure that the circuit has actually been de-energized. Remove the black, insulated conductor from the breaker and pull it carefully away from the breaker and the live bus bars. Remove the circuit breaker from the panel. Depending on the make and model of your breaker panel, the breakers may simply snap out of the panel, or you may have to remove a screw from the bus bar before you can remove the breaker from the panel. In the latter case, turn off the main breaker before removing the screw from the bus bar. The bus bar on the load side of the main breaker will be de-energized when you switch the main breaker off, but treat it as if it were "hot" anyway. Always treat electrical circuits as if they were "hot" even when you know they aren't.
- 3). Disconnect the branch circuit's white, neutral wire from the "neutral bar." Depending on the make of panel, the bar may be located along one side of the panel or along the bottom of the panel. Install the ground-fault circuit breaker in the panel. Unlike the conventional breaker that you removed, the single-pole ground-fault circuit breaker has a white "pigtail" wire and two terminal screws instead of just one terminal screw. Connect the white "pigtail" lead to the neutral bar where the original branch circuit neutral wire was connected. Reroute the circuit neutral conductor and attach it to the bottom screw on the single-pole ground-fault circuit breaker. Shorten the neutral conductor's length and re-strip as necessary before attaching it to the new breaker. Attach the black, "hot" conductor to the upper screw.
- 4). Turn the single-pole ground-fault circuit breaker "on" and test the circuit with the DMM. If the circuit is still de-energized, press the "Reset" button on the breaker. Some breakers ship in the "Tripped" position. Once the circuit is live, press the "Test" button on the breaker to make sure that it's actually providing GFCI protection. When everything is working properly, replace the panel's inner and outer covers and trim.
- 5). Check the protected receptacles to make sure that GFCI protection is present at each receptacle. Plug the GFCI receptacle tester in each of the receptacles and push the built-in test button. The GFCI button on the circuit breaker should pop out to the tripped position, and the circuit to the receptacle should become de-energized, requiring you to press the "Reset" button on the breaker.
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