GFCI outlet seems to trip several times a week

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Use a meter to test the resistance between the Equipment Grounding Conductor (EGC) and the Grounded Current Carrying Conductor; most call this the neutral.

If you get any measurable value you may have found the problem. A fault between the EGC and the energized conductor will trip a GFCI immediately on every attempt to reset it. A fault in the neutral that allows current to flow to the EGC will only trip the GFCI when a load is applied and current is flowing. Any load on that circuit that operates somewhat randomly could be the culprit. Examples include refrigerators and freezers, sump pumps, garage door openers, lighting timers or motion sensers...

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Tom
 
Use a meter to test the resistance between the Equipment Grounding Conductor (EGC) and the Grounded Current Carrying Conductor; most call this the neutral.

If you get any measurable value you may have found the problem. A fault between the EGC and the energized conductor will trip a GFCI immediately on every attempt to reset it. A fault in the neutral that allows current to flow to the EGC will only trip the GFCI when a load is applied and current is flowing. Any load on that circuit that operates somewhat randomly could be the culprit. Examples include refrigerators and freezers, sump pumps, garage door openers, lighting timers or motion sensers...

--
Tom

Tom
I looked for a google language translator from smart electrician to english, they did not have one :) All kidding aside, not sure what all that means or what to do


Today I went to home depot, bought a 15A GFCI (leviton) and just swapped it in. Turned the circuit breaker back on and seems to be wired OK. Green LED is on, and when I press test, it kills the power as it should. Using my old school tester as before nothing trips which is encouraging. Old one tripped basically each and every night this week so I will know in the morning if we are good.
 
Use a meter to test the resistance between the Equipment Grounding Conductor (EGC) and the Grounded Current Carrying Conductor; most call this the neutral.

If you get any measurable value you may have found the problem. A fault between the EGC and the energized conductor will trip a GFCI immediately on every attempt to reset it. A fault in the neutral that allows current to flow to the EGC will only trip the GFCI when a load is applied and current is flowing. Any load on that circuit that operates somewhat randomly could be the culprit. Examples include refrigerators and freezers, sump pumps, garage door openers, lighting timers or motion sensers...

--
Tom

Tom: So you're saying (if I read this right) that if there is a current between the neutral and the ground, that the GFCI will allow it; but once there is (downstream) use on the circuit, the GFCI will trip.....?
 
Rhedayi

I think you are good now.


GFCI does not use the EGC (bare copper equipment ground wire)at all. They can be installed in old wiring where there is no EGC and protect you. They are looking at an imbalance going out to a device and coming back. So if your body or anything else is making a path to earth ground some of the current is going thru you to the earth and not all is returning to the common wire (White).

I think what Tom is saying is the EGC and the common are connected at the panel so measuring resistance between them should be very low. I understood it that far. I don’t know what kind of a fault he was talking about that would go between the two and show up as I would think they are the same potential. Maybe he can explain it again. I do know they are set very sensitive and I could see a bug or moisture going to ground triggering it.
 
OK this morning, it is still working, looks good so far, thanks !!
 
OK this morning, it is still working, looks good so far, thanks !!


We had it figured out in post #3. :beer:

Glad it’s working. Sledgehammer trouble shooting is often the best.
 
You guys Rock Thank alot, hit me up with eye related questions, that is my field of work !
 
Tom: So you're saying (if I read this right) that if there is a current between the neutral and the ground, that the GFCI will allow it; but once there is (downstream) use on the circuit, the GFCI will trip.....?

No! With no load there will be no current between the neutral and the ground. Once a load is applied to the circuit the current on the Grounded Current Carrying Conductor (Neutral) will take all available paths back to the source. If there is a neutral to Equipment Grounding Conductor (EGC) fault that has a low enough impedance then the current that is leaking into the ground, and thus not returning on the neutral, will exceed the trip point of the GFCI and it will open.

GFCIs respond only to an imbalance of current flow between the energized and neutral conductors. When that current flow differs by more than five milliamperes the GFCI opens the circuit. Without current flowing there can be no imbalance. Current will only flow when a load is applied such as when the garage door opener is activated or a refrigerator gets too warm and it's thermostat connects the compressor to the circuit.

A common Wiggington type solenoid voltage tester or Wiggy draws about Seven milliamperes of current when applied accross a One Hundred Twenty volt circuit. Testing between neutral and ground on the receptacle outlets of a GFCI will seldom trip the GFCI open unless the circuit is already under load and current is already flowing. Test between the energized blade and ground will draw Seven milliamperes of current from the energized conductor that is not flowing through the Neutral of the GFCI mechanism. That imbalance will trip the GFCI.

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Tom
 
Small update
I reset the GFCI this am and it was already tripped by noon, no sprinklers and very little dew overnight because winds kicked up here in so cal. I took my trusted old school voltage tester and tested the outlet...as expected NOTHING. I reset it and tested the top outlets fine, the lower outputs IT TRIPPED, hmmm reset GFCI again and test THIS time 120V, test again trip...does this further point to a GFCI that is faulty ? BTW after I reset it, I tested the other garage outlets and they were on and they do not trip the GFCI

this picture is from ebay, I have one of these that is orange

How do you explain what was going on internally in his GFCI to have the top outlet fine and the bottom tripped every time. One would think internally they are in parallel just as the downstream loads are. It almost sounds the interrupter circuit is different for top and bottom but all the loads are off the top.
:confused:
 
we are still good, so I consider it a fix !!! Thanks everyone and happy thanksgiving
 
Tom: So you're saying (if I read this right) that if there is a current between the neutral and the ground, that the GFCI will allow it; but once there is (downstream) use on the circuit, the GFCI will trip.....?

A functioning GFCI will not permit any current above Five milliamperes to escape the circuit without opening the supply conductors to that circuit. When there is a fault between the Load side white wire and the Equipment Grounding Conductor (EGC) but there is no load on the circuit then no current flows and the GFCI does not trip. When a load is applied to that faulted white wire the current will take all paths back to the source in proportion to the impedance of the paths that are available. Because of the fault between the white wire and the EGC the current to and from the load will divide at the fault between the white wire and the EGC. As long as the fault has a low enough impedance to carry Six or more milliamperes the GFCI will trip. The thing that is different about a fault on the white wire is that there is no current present on the white wire until a load is connected to cause current to flow in the circuit.
 
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