Just inspected a townhouse that has GFCI breaker in the Gould panel, also GFCI receptacle in each bathroom. When the breaker’s test button is tripped, it cuts current completely to the bath outlets (and also the exterior outlet). But, when the test button on the receptacle is tripped, the outlet still shows 30VAC, Open Ground and Open Neutral. 1st - this tester is one I just picked up at Home Depot, is this accurate? I don’t carry a multimeter with me… Maybe indicate a wiring issue? I’ve never seen something like this.
I would note exactly what I observed and recommend further evaluation by a qualified electrician. I am not an electrician, nor claim to be to my clients. I am sure an electrician will chime in soon with much more helpful information.
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Of course, that’s my plan… just hoping to understand the cause for my benefit.
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Me as well. I will be following your post, thanks for posting!
I misread your post… before you pressed the test button on the receptacle, did the tester show correct wiring? Did the reset button work?
I do not believe the tester is picking up any voltage over 30V as shown in your pic, it just shows >30 when there is a wiring condition such as missing neutral (GFCI tripped). Try it on a different GFCI outlet after tripping it. Why it didn’t show you >30 when the breaker was off, I’m not sure. It appears as if the tester sees the hot present after the GFCI receptacle is tripped, thinking neutral and ground are missing (as indicated by the tester). Why would ground be missing? I’m not certain how it is able to determine there is a HOT without either ground or neutral.
Simon, before testing, the tester showed 120vac, and “correct wiring”. As soon as the TEST button on the receptacle is pressed, it goes to 30VAC, “OPEN GRND NEUTRAL”. But when the TEST button on the BREAKER is pressed, it immediately goes to 0 VAC “OPEN HOT”. I’m thinking the GFI Receptacle is either wired incorrectly or is faulty… was hoping someone would be able to enlighten me… not that it matters, this is an inspection for a friend - a Realtor that has referred me numerous times…buying as an investment property. BTW - when the test button is pressed on the receptacle, it does NOT trip the GFCI breaker in the panel. And also, at the kitchen GFCI, yes, it shows 0VAC when the receptacle test button is pressed.
It is a “ghost voltage” that appears only when the outlet is partially disconnected. Notice it does not appear when the entire circuit is disconnected by the breaker. Why would require further diagnosis of other items in the circuit. Just to clarify there need be no “current” flow at all to indicate a voltage (high impedance meter). Current only flows when the circuit has a load (toaster, light bulb, motor, dead short). If you used a low impedance meter (higher load) for your test you would probably not get a voltage reading for either condition.
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Interesting - thanks for the insight.
I’m going to bump this up again as I do not see that this issue has any newer threads (directly related to this) and was not actually answered/solved. I have found this same reading a few times in the past and then again today.
Other GFCI circuits seamed to be fine but the circuit in the (unit’s) garage is showing this same anomaly. The home is a condo and the multiple garages are completely separate by the way. I’m going to just call it out for an electrician to investigate. I’m guessing that somehow the wiring is wonky or possibly the GFCI control receptacle is somehow defective. The other GFCI’s are the same brand and type throughout the home but not getting this wonky reading after tripping (button or with tester). Used another tester and still getting the wonky reading.
So if anyone has any ideas on why, I’d love to hear them.
As a side note, almost all receptacle in the home and at the garage are installed with ground UP…I hardly ever see this except for switched wall receptacles and a couple of homes where I find out the homeowner is some kind of electrical engineer…or used to wire Hospitals in the past…
Your tester says open ground. Did it trip with the test button on the device?
Ground up, ground down doesn’t matter since it’s a personal preference not a code issue.
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Very hard to “Test” the tester if you don’t have an alternate method of testing that outlet. i.e. a cheap 3 light tester, a DMM or my personal choice a “wiggy” solenoid tester.
Personally I don’t trust that type of battery operated tester for these measurements because like a DMM it is a high impedance device. This means it provides no load to the circuit under test and is prone to reading “ghost” voltages.
Plus it takes batteries which is a drawback in equipment usefulness in my book (got enough damn batteries).
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True, but just wondering if the it was the homeowner that changed these or if the electrician did this. did not have access to the other dwellings or could have seen if this was from when constructed (built 2000) I very seldom see that here except at hospitals and recent years electricians have done this on switched outlets/receptacles.
Strange that this one device had a different reading with your tester but it does show open ground which is unusual.
Regarding the ground up/down debate there is no right or wrong although you may hear quite a bit of arguing over it.
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I have run into this with that Klein tester 3 times before.
If you stick a multimeter into that you’ll probably see 2-3 volts.
I figure it was induced voltage from a wire next to it that is live or it’s voltage on a traveler 3-way.
If you stick a different, LED only circuit tester, it’ll stay dark or it has in my cases.
When I see this one, I grab one of my other testers and they are off.
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I have seen this same thing with this tester quite a few times. I asked an electrician friend - he offered a few theories, but nothing concrete. With the “OPEN NEU” display, I wondered if the HOT / NEUTRAL were crossed, and when tripped, the GFCI actually stopped the Neutral…? Or the outlet itself is faulty…At any rate, I have recommended an electrician evaluate it when I have seen this.(And I don’t put my guesses in my report!)
Does this tester always say open GRD when the test button is tripped?
I am use to the term, “phantom” voltage.
Funny to see the receptacle labeled GFCI Protected circuit.
I see labels are reserved for outlets protected by a panel GFI and no ground.
Sorry for the edit, Bob.
Is that a Canada thing? The NEC does allow the labels on receptacles even when theyre not required.
I was in a restraint and my Surface Pro Laptop Go 2 was running out of battery power so I could not complete / edit the post. Ops. Not a Canadian thing.
I was eluding to, this would be a First for me having inspected thousands of manufactured GFCI outlets in Kitchens and Bathrooms. I can not recall any one time having seen a self glue label. Typically those labels are reserved for, No equipment ground.
Section 406.4(D)(2)(c) requires that the replaced receptacles that are not of GFCI-type but protected by a GFCI device such as a GFCI circuit breaker or the load side of a GFCI-type receptacle be marked with both “GFCI PROTECTED” & “NO EQUIPMENT GROUND”.
I was referring to your comment that “labels are reserved for outlets protected by a GFI panel or device breaker.” that’s all. There is nothing that requires labels to only be used for circuit breaker protected circuits.