Tips for Converting to Three-Prong Outlets
LESLIE: Randy in New York, welcome to The Money Pit. What’s going on?
RANDY: I recently moved into a house with – a lot of the outlets have the two-prong outlets …
RANDY: … and I wanted to put in three-prong and grounded outlets. I took wire from the grounding lug to the wooden – the metal box – to make a ground and it still shows open ground.
TOM: Yeah, well that’s because the metal box is not grounded. The ground in a two-prong system is through the neutral. Now, there is a way to create ground protection – and this is something that only an electrician should do. But it’s possible to install a ground fault circuit interrupter outlet – this is the kind with a test and reset button in it – and install it in such a way that if there is a short to ground that it’ll trip the outlet itself and turn it off. That will give you, actually, a grounded outlet without the entire system being grounded. But you can’t just join a wire to the metal box and hope that it’s connected through the ground because that whole circuit would have to be connected through the ground; the box, the conduit through a grounding right outside and that’s just not the way that’s installed. The ground is designed to go through the neutral in a two-wire system.
RANDY: Well, I’ve done that before and it showed – with a tester it would show a completed ground.
TOM: Well, maybe in this particular case there’s a break in that ground somewhere. It’s not actually connected through.
RANDY: So I need to go – every place that I wanted a grounded outlet I need to put a GFI in?
TOM: Either that or run a separate wire. Run a ground wire through the entire circuit. Yeah, I mean it’s not easy to do this conversion.
TOM: And you are grounded because you’re grounded through the neutral.
TOM: But if you want to have a three-prong outlet and you want it to be ground protected you could install a ground fault but it really should be done by an electrician …
RANDY: Right, right.
TOM: … so it’s done correctly.
RANDY: Right (INAUDIBLE).
TOM: Yeah, that’s what I would recommend; certainly for your bathroom, your kitchen and areas like that …
TOM: … so you definitely would have that protection.
RANDY: Where there’s danger of water.
TOM: Exactly. Randy, thanks so much for calling us at 888-MONEY-PIT.