Install a GFCI


Wiring for a ground fault circuit interrupter (GFCI) depends on where it falls in the circuit and whether you want it to protect the other outlets.

Turn off the power and look into the box to see whether the receptacle is at the start, at the end, or in the middle of a run. If it is in the middle or at the start, it can protect other outlets. Consider any drawbacks to protecting outlets in the circuit after the GFCI. Do you risk cutting off power to a freezer if the GFCI trips, for instance? The following shows how to protect a single outlet.


About 25 minutes to remove a receptacle and install a GFCI

Screwdriver, side cutters, strippers, lineman's pliers, voltage detector

Stripping and splicing wire

Lay a towel or small drop cloth on the surface below the receptacle.

GFCI receptacle, wire nuts, electrician's tape

Step 1

Turn off the power. Test to make sure the power is off. Look inside the box to see where in the circuit the outlet falls. This box has two cables coming into it, making it a middle-of-run outlet. Disconnect the wires.

Step 2

If you want GFCI protection only for the outlet you're installing and not the ones down the line, pigtail all the white wires together and connect the pigtail to the terminal labeled WHITE LINE.

Step 3

Pigtail all the black wires together and connect the pigtail to the terminal marked HOT LINE.

Step 4

Pigtail all the ground wires together and connect the pigtail to the green ground screw. Wrap tape around the GFCI to cover the terminals. Attach it to the box and cover with a cover plate.

What If There Is Only One Cable in the Box?

If only one cable enters the box, the receptacle is at the end of the line. Connect the black wire to the BLACK LINE terminal and the white wire to the WHITE LINE terminal. Connect the ground wire to the ground screw, pigtailing it to the box if the box is metal.

Comments (6)
jdr06451gmail wrote:

Trying to wire GFCI and a protected receptacle into the same box for 4 outlet set up. When I wire protected receptacle to LOAD side and connect it to the ground, the GFCI test fails. If I disconnect ground to protected receptacle, GFCI tests OK but protected receptacle tests ┐open ground┐. What am I doing wrong?

1/28/2016 09:45:58 AM Report Abuse
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One Hour or Less

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