Can a Ground Fault Interrupter be safely used in a house that uses an ungrounded outlet?

Question

Would it provide the same protection as a grounded outlet?

Answer 1

First, many answers are wrong about a GFCI needing a safety ground. A GFCI will still function without a grounding connection (bare wire to green screw), and the code even allows a GFCI to be used to replace 2 wire (ungrounded) outlets (but must be labeled that it has no equipment ground). So the answer to the first question is a GFCI CAN be safely used in a house that has ungrounded outlets.

The second question, is NO, it will not provide the same protection as a grounded outlet--for things that have a ground pin (3rd pin on the plug). For 2 wire devices the GFCI will be better than a non-GFCI 2 wire receptacle. When you are missing the equipment ground, a fault in your appliance/tool instead of causing the circuit breaker to trip, will make the case of the appliance hot. You will get a shock from it, and trip the GFCI, assuming the GFCI is working. The reasons a GFCI is not as safe is 1) you WILL get a shock. A GFCI does not prevent shocks, it shuts them off before being fatal. 2) SOME people will have a lower shock level and can be killed even with a working GFCI. 3) GFCIs have electronics in them, which can fail, leaving you with no protection.

Lastly, some answers suggest the ground for your outlet should be connected to a ground rod or water pipe. This is not allowed and will do no good. You need a low impedance connection to the neutral at the service (no connection any place else).

Answer 2

You need to update the wiring; you can't properly ground an outlet without 14/2 wire which includes a ground. The outlet would not be safe--like a gun with blanks.

Answer 3

NO, because it does not have a ground. The person that answered that the White wire is a ground is wrong! The White wire is the Neutral and the Red or Black wire is the positive or HOT.

Considering that many water lines are NON-Metallic trying to use a water line for a ground is not a good idea either.

Answer 4

It can be used there. It will protect its own outlet and others further down that brnach circuit.

The protection it will provide is that it will shut off the power to the outlet if there is a dangerous flow of current from the live wire. If it hasn't failed and if it has been tested to be sure of that it will give the same protection.

Answer 5

No. It uses the ground to detect any current and shuts the hot wires off. If it isn't connected to ground, then it can't detect any shorts. You can always run a separate ground line from a grounded water pipe. Ask an electrician about getting some ground wiring installed.

Answer 6

The problem is if you experience a large spike or surge, the UPS/Surge protector cannot clip it. They clip these surges and spikes by momentarily creating a short circuit to ground. Not too much you can do about this safely. It is possible you can ground your UPS/Surge protect to the cold water pipe under a sink or to a radiator if you have one or the other close by. Caution: you have to make sure of the correct polarity where your UPS/Surge protection is plugged in.

Answer 7

NO.

The "Ground Fault Interrupter" must be grounded to function properly.

In older homes you can use one if you add a ground wire and run it directly to ground using a solid copper grounding rod or going directly to the same place your electrical service box is grounded.

No matter how it is installed it MUST have a functioning ground with minimal resistance.

Answer 8

"ungrounded " out let is grounded!= white wire. ground on new outlet [3prong] is double grounded for safety if 1 ground disconnects. ground fault means trip if ground is faulted. i guess yes but call manufacturer.