How To Change A Two Prong Outlet To Three

Luckily, metal boxes attached to armored, or BX, cable—a type of wiring commonly found in old houses—generally are grounded; the cable’s flexible metal jacket serves the same purpose as a dedicated ground wire.

Outlet Versus Receptacle: What’s the Difference?

Outlet—Anything that has a power current taken out and utilized. For example, appliance outlets, smoke detector outlets, and lighting outlets. Receptacle—Is an outlet. A contact device is installed at the outlet for the attachment of an attachment plug.

Why Install GFCI?

Even if an outlet box isn’t grounded, installing a GFCI in it will still protect you (and your tools and appliances) from ground faults. But an ungrounded GFCI can’t safeguard sensitive electronics, such as a computer or phone, from the interference caused by stray currents. The National Electrical Code requires you to stick a label on the receptacle that reads, “No equipment ground.” These labels come in the box with a new GFCI.

How to Replace Two-Prong Outlets to Three:

Follow the steps below to learn how to ground an outlet.

Step 1: Check for ground

Insert one prong of a circuit tester into the receptacle’s hot slot (the shorter one), and touch the other to a screw that secures the cover plate. The tester should light up. If it does not, the box is not ­grounded. You can install a GFCI (see steps below), or call an electrician to fix the wiring.

Step 2: Remove the old receptacle

Turn off the power at the ­breaker panel or fuse box. Unscrew the old receptacle from the box and detach the wires.

Step 3: Connect the new receptacle

Attach the black (hot) wire to the brass terminal and the white (neutral) wire to the silver. On a GFCI, use the terminals in line with the “line” label on the back of the receptacle. (If your box is not grounded, skip to Step 6.)

Step 4: Fasten the ground screw

This green screw, sold in hardware stores, fits in a threaded hole in the back of the box. Hook one end of an 8-inch green grounding wire or pigtail (also available at hardware stores) to the screw and tighten it.

Step 5: Ground the receptacle

Secure the other end of the 8-inch grounding pigtail to the green grounding terminal on the three-prong or GFCI receptacle. Insert the new receptacle into the box.

Step 6: Turn on the power

Use a circuit tester to make sure the circuit is working.

Steps for Installing a GFCI Outlet

Resources

A room will have to be rewired if there isn’t a ground present. However, if you want to have a grounded, three-prong receptacle without rewiring, you can also use a ground fault circuit interrupter (GFCI) found at any home center.

Shopping List

GFCI outlet Cover plate

Tools