Lisa Bea Smith
What to do with 2-Prong Outlets?
Updated: Sep 4, 2019
Two prong outlets found in many older homes (early 1960s and before) do not have a ground wire. (The NEC required a grounded receptacle for laundry areas in 1951) However, in many older homes, the metal receptacle box attached to the armored (BX) cable often provides a ground. (The cable's flexible metal jacket provides the same protection as a dedicated ground wire.) Adapters can be used if the metal receptacle box is so grounded.
Even if the receptacle box is not grounded, installing a GFCI receptacle will still provide protection from ground faults. (NOTE: An ungrounded GFCI will not safeguard sensitive electronic equipment, such as a television or computer, from the interference caused by stray currents.)
To check for a ground, insert one prong of a circuit tester into the “hot” slot of the receptacle (the shorter one), and touch the other prong of the circuit tester to the screw that secures the cover plate. If the box is grounded, the tester will light up and these receptacles can be replaced with standard 3-prong receptacles. However, if the tester does not light up, the box is not grounded and the 2-prong receptacle should be replaced with a GFCI receptacle to protect from shocks.
1. Turn off power that is feeding the 2-prong outlet. (Test and verify that power is off before beginning work.)
2. Remove the screw in the center of the coverplate to the outlet coverplate.
3. Remove the two small screws holding the 2-prong receptacle to the receptacle box (top and bottom).
4. Carefully, pull the receptacle out from the box far enough to access the wires attached to the receptacle.
5. Remove the wires from 2-prong receptacle. (There should be a black wire and a white wire.)
6. Connect the (neutral) white wire to the silver screw and connect the (hot) black wire to the brass screw on the new GFCI receptacle. (Use the terminals marked ‘LINE’.)
7. Carefully fold the wires back into the receptacle box and seat the new GFCI receptacle in the box. Fasten in place with the two small screws removed in step 3.
8. Replace the coverplate.
9. Turn the power back on to the receptacle.
10. Verify the ‘RESET’ button is pushed in to ensure that the GFCI receptacle in ‘on’.
11. Verify that there is power to the receptacle.
12. Press the ‘TEST; button and verify that there is no power to the receptacle.
13. Press the ‘RESET’ to restore power to the receptacle.
14. Be sure to place the ‘No Equipment Ground’ sticker on the coverplate.
This electrical outlet will now protect against shock even though it is not a grounded outlet!