Installing grounded outlet without grounding wire (USA)

[Nelson]

Hello everyone,

I may need to install a standard grounded outlet on a circuit that does not have a safety grounding wire (it only has a two-wire cable). I seem to remember that you could safely and legally do that as long as you used a GFCI outlet. First of all, is that true? If so, do I have to buy a special GFCI for that purpose?

Thanks,
Nelson

[Mike]

I'm not positive on how you would set up something like that. A GFCI sounds reasonable, but they're a bit more expensive.

[Vince]

According to the Canadian Electrical Code, if no grounding is available, you must use a device that properly detects current leaks (to ground or you!). A GFCI outlet is acceptable, and so is a standard outlet with a GFCI breaker.

Now the NEC serves as a base for the Canadian Code, so I guess it's pretty much the same.

[Nelson]

Thanks for the replies. I am installing an outlet on an old lighting circuit. It may be grounded, but because of its age and because it was previously used only for lights, it may very well be ungrounded.

[Jace the Gull]

Houses from 1962 and later all HAD to have grounding outlets...but before 1962 did not require it.

If the wires are armored cable, those can be substituted as grounding, as long you have those metal conducts be connected to some sort of grounding...I am not sure on all the details though...

[Nelson]

As I was afraid, it is only a two-wire ungrounded circuit as seen here. For now, I will use an old stock two-wire outlet until I find a good deal on a GFCI. I may find that I don't need a grounded outlet anyway.

[Vince]

Installing an ungrounded outlet as a replacement is actually permitted. And even if it's "illegal", it is not really dangerous. The reason being, you can only connect 2-prong cords into those, unless you cut the ground pin on a 3-prong cord, but that's another story!

If you make sure you strip and loop the wires properly (with a nice C shape that should close and form an O when you tight the screw terminal), there will be no problem or danger.

[Jace the Gull]

As I was afraid, it is only a two-wire ungrounded circuit as seen here. For now, I will use an old stock two-wire outlet until I find a good deal on a GFCI. I may find that I don't need a grounded outlet anyway.

They STILL make 2 prong outlets for replacements actually! You will find them in Home Depot or Lowes. The reason they make the 2 prong outlets is to prevent plugging in anything that uses grounding!!! I mean if you installed a outlet with grounding but not wiring it and someone PLUGGED in something that uses grounding and there was a problem.....that's why the 2 prong outlets are STILL made, ONLY for replacements, not for new installations.

[Nelson]

Yeah, I don't see any danger in using a two-prong outlet in this case. As far as wire termination, I am using stranded THHN with crimp spade terminals that fit under the screw heads. Now that the job is done, it really looks nice and works well, too!