How to Wire a 240V GFCI Receptacle
- 1). Turn off the main breakers in the breaker box before beginning to work on this installation. Use a multimeter to verify that the power is off to the power strips. Either select a new spot on in the breaker box for the GFCI breaker or remove the regular 240-volt breaker that will be replaced with the GFCI breaker.
- 2). Disconnect the red and black wires from the old 240-volt breaker by loosening the screws that hold them in place. Locate the associated white wire and disconnect it from the ground strip. Store the old 240-volt breaker for future use or discard it.
- 3). Use wire strippers to remove about 1/2-inch of insulation from the white pigtail that extends from the GFCI breaker. This wire should be connected to the neutral bus in the breaker box. If there is a bare ground wire in the 240-volt cable, connect it to this bus as well.
- 4). Slide the ends of the red and black wires into the corresponding terminals on the GFCI breaker. These will be similar to the terminals on the old breaker. Tighten them securely into place. Attach the white wire to the final terminal on the GFCI breaker and tighten the screw. Snap the GFCI breaker into the box. The receptacle should be wired just as it was before: with the red and black wires attached to the hot terminals and the white wire to the ground terminal.
- 5). Turn on the main breakers. Push the test button and make sure that the breaker opens. If it does not open, double check the installation after turning off the main breakers again. If it does open, the GFCI protection is in place for your 240-volt receptacle.
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