Hot/grd reverse on GFCI

[mridgeelk]

Is this hot/grd reverse caused by the GFCI being the second one on the circuit or something else? Thanks, Ed

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[inspector57]

I have seen this before and heard other inspectors come across it. I don't know how it happens, but occasionally on that particular brand of older GFCI's it will reset showing reversed connections. I have only seen it a few times and always on the older GFCI's with the black and red buttons.

I do not believe it is related to any particular wiring issue, just an internal problem in the device itself.

[Billy_Bob]

I think all you need to do is report the problem, but...

I would use a voltmeter, a long length of wire to a known good ground (not electrical), and test each prong on various outlets for voltage. (The wire for testing can be cheap small gauge speaker wire or whatever.)

A known good ground would be a ground rod for the electrical system, next best would be a cold water pipe going into the ground and hopefully the underground portion is not plastic PVC.

So using that ground would give you a good reference to see exactly what is going on. Then there should be little or no voltage reading on neutral and ground.

Of course if you get 120 volts on the ground prong of an outlet, this could be a VERY DANGEROUS situation! They should call an electrician ASAP!

Then all grounds to outlets in a home are tied together at some point (or should be). So the problem might be in another part of the house!

Could also be that particular outlet tester has weird readings on certain GFCI's?

[Jim Katen]

Is this hot/grd reverse caused by the GFCI being the second one on the circuit or something else? Thanks, Ed

The first thing to do is trip the GFCI and reset it again. As Jim said, some of those GFCIs behaved like this when you tripped them and then only lightly pressed the reset button -- you'd get this hot-ground reverse reading. I don't know why but when you reset them firmly, the "problem" went away.

If the problem remained, I'd do a Billy Bob said.

- Jim Katen, Oregon

[mridgeelk]

The initial time I tested the GFCI it showed the incorrect reading, I tripped and reset the GFCI three times. The first two times it showed the correct reading when reset, the third time it showed the incorrect reading again. So I think it must be a partial reset as you suggest. Being that the GFCI does trip when the reverse reading is indicated, does this reading indicate an actual safety issue?

Is this hot/grd reverse caused by the GFCI being the second one on the circuit or something else? Thanks, Ed

The first thing to do is trip the GFCI and reset it again. As Jim said, some of those GFCIs behaved like this when you tripped them and then only lightly pressed the reset button -- you'd get this hot-ground reverse reading. I don't know why but when you reset them firmly, the "problem" went away.

If the problem remained, I'd do a Billy Bob said.

- Jim Katen, Oregon

[Jim Katen]

The initial time I tested the GFCI it showed the incorrect reading, I tripped and reset the GFCI three times. The first two times it showed the correct reading when reset, the third time it showed the incorrect reading again. So I think it must be a partial reset as you suggest. Being that the GFCI does trip when the reverse reading is indicated, does this reading indicate an actual safety issue?

Probably not. But I honestly can't remember what happened the last time I tested one. I'd just replace the GFCIs.

- Jim Katen, Oregon