Does anyone have any idea why an outdoor weather cover would set off a voltage sniffer and continue to do so even after I trip the GFCI upstream and cut power to the receptacle? The three-light tester reads OK and I have touched the cover without a shock.
I should add… this is my own home. It’s a new receptacle on old wiring, some of it UF buried in conduit. The voltage disappears when I throw the breaker, but not when I trip the GFCI at an upstream receptacle. Based on this, I’m thinking the ground might be compromised by a live wire upstream of the GFCI. Does that make sense? I’m trying to figure out what to look for. If this were an inspection, I would just say, “consult a licensed electrician”…
You say the three light tester reads “OK”. What does this mean?
Does it read ok as in live and wired correctly even when the GFI is tripped?
Or ok as in dead, no lights?
Also, what is a “sniffer”? Do you mean a non-contact voltage tester? Like a volt-tick?
Yes, the tester has the correct two-light display when the circuit is powered. When the GFCI is tripped, the tester is dark. And yes, I’m talking about a non-contact pen-type voltage detector.
I realized this morning after I’d turned the breaker off that two old ungrounded indoor receptacles are on the same circuit. I’m thinking that a previous homeowner must have spliced into an ungrounded circuit and created some sort of bootleg ground that is carrying a small amount of current. Maybe they even tied it into a neutral? Looks like a project…
If you do not figure it out…let me know…I am only about 35 minutes from you and will look at it for you if needed.
It also sounds to me off hand like the receptacle was added to the old circuit and is not actually downstream of the GFCI…otherwise the GFCI being tripped ahead of it would kill it…
Check to see if they did not tap the old circuit and connect to the LINE side of the circuit...rather than the load side of the GFCI protected portion of the circuit.
Thanks, Paul. I’ll keep you posted.
Paul, just to be clear, the GFCI does trip the receptacle itself. It just doesn’t trip the weather cover! This sort of thing frightens me because it’s something I wouldn’t notice during a normal inspection.
I have to ask.......when you say it wont trip the "weather cover" are you expecting the COVER itself to do something...lol.....now you are confusing me fella...lol..and I have been doing this for 20 years....lol The cover itself should not do anything...thehe...ok....maybe you better just call me..540-607-0116 before i fly out to California....I hate flying !
Those non-contact testers can fool you, especially on older two wire systems. My tester lights up when I get within 6" of a receptacle in my house.
Also, keep in mind that when you trip the GFCI you still have power to the line side wiring and that may be what your tester is detecting.
Like any tester non-contacts should not be relied upon solely. Use a good voltage meter and use the 3 step test (1.Test a known live circuit to test the meter, 2.Test the circuit in question, 3.Test a known live circuit to re-test the meter) to verify that it is working properly.
I think he stated the GFCI is up stream and tripped…I agree on the non-contact tester…always verify as some will even detect as low as 30 volts…but I think the issue may be an improper wired GFCI upstream…I am sure Jeff will keep us posted.
Hi guys. I was a long time in getting back on this thread; I’m sure you all thought I’d been electrocuted. Paul, I’ve been meaning to call you anyway; hopefully I’ll get to it sometime this week.
I have used a multimeter on the circuit. The ground wire is what what conducting current. I knew the non-contact tester wasn’t lying when I got shocked by touching the weather cover (nothing serious, obviously). The problem exists upstream of any GFCI and I discovered it on another circuit as well.
I should have been tipped off to the source of the problem when the circuit tester indicated a proper ground on a circuit I knew was not connected to earth via the panel. Both of these circuits are wired with 3-wire romex at the receptacles, but older 2-wire in hard-to-reach parts of the crawlspace and chase. Although I can’t see all the wiring, my guess is that someone rigged up a makeshift ground which is somehow in contact with something live (12V doorbell circuit, maybe?)
Anyhow, since the GFCIs bestow some of the benefits of a true ground and the circuit wasn’t really grounded anyhow, what I did for the short term was to just disconnect and isolate the ground wire from the upstream receptacle. Now it’s running like an old-fashioned 2-wire circuit on a GFCI and I can touch the weather cover all I like.
I’d still like to figure out where the stray current is coming from, and someday I’ll rewire everything back to the panel.
Jeff, maybe you have a bootleg ground on this circuit and you now have some neutral current on the grounding wire, which is in direct contact with the metal box.
Yeah, the bootleg ground is what I’ve been suggesting. If it’s tied to a neutral, however, I think it’s a neutral on a different circuit.