Can I install GFCI plug when the room has no grounded plugs?

Question

We just purchased an older home, and the upstairs outlets (we were told during home inspection) are not grounded. I run a small business out of my home, and I need grounded plugs for my equipment. The plugs upstairs all have three-prong female, but I am not sure how to go about finding out if they truly are not grounded or what. Some of my equipment is used around water, so I believe I need GFCI and not regular grounded plugs.

Thanks in advance!

Answer 1

If there is no ground wire, then one would have to be installed. This can be done by driving a 5 foot long steel rod into the ground until it is at least 6 inches below ground level and about 3 feet away from your building. Using a clamp, attach a 14 gauge bare copper wire to the rod. The other end is to be attached to the GFCI plug in the proper place           ( usually onto the green s***w) If at all possible, all the plugs should be grounded or someone will get seriously hurt.

Answer 2

It is perfectly acceptable by code to install a GFCI on an ungrounded circuit, and it will protect just as well.  As another poster said, they work by sensing differential currents, and do not depend on the ground connection.

By strict code though, you should attach a label to the outlet which says "No Equipment Ground", so a user knows that it is truly ungrounded.

Which brings up the issue of your business equipment - for best protection from surge suppressors, etc., you should have a true grounded circuit.  Probably well worth running a fresh new grounded line to the room.

Answer 3

yes, a gfic plug operates on 2 principels one is ground the other is amps,the plug trips when there is a diffence in voltage and amp draw.thats why when you plug up a blowdryer t a gfic, alot of times it will trip the breaker,because its pulling more amps than the plug will carry.

Answer 4

go buy a outlet tester at your local hardware store .they are less than 10 dollars.it plugs into the outlet and tells you if the outlet is wired correctly.but,it can be fooled.if you have a 2 wire cable from the panel to the room,i've known people to use the grounded conductor (also known as the neutral) also as the grounding conductor (also known as the ground).they are bonded together at your first means of disconnect only.it wont give you a true ground ,but it will trip the circuit under fault.if you cant get a new cable pulled,i would do it.its better than not having a path to ground for your device your using.you might not even need a gfi outlet.,home inspector should have told you.    d2 is wrong .a gfci works by detecting a unbalance between amps of hot and neutral.and trips in less than 1 cycle upon detection.

Answer 5

to see if they r grounded just remove the cover, unscrew the top bottom screws on the outlet and look for the small copper ground wire....

lic. gen. contractor