GFCI Breaker Always trips

Status
Not open for further replies.

MattS87

Senior Member
Location
Yakima, WA
I recently installed a hot tub circuit for my neighbor running a 40A breaker and #8 wire from the main panel to a 50A spa panel and #8 wire in PVC to his new hot tub. After energizing the circuit and verifying everything worked I walked away. The next day he tells me the GFCI breaker tripped and won't reset. I had to work but had him do some simple checks and he ended up replacing the breaker, putting in an exact replacement which worked.

9 days later he tells me the same problem has happened. This time I wanted to troubleshoot to look for installation problems. I rechecked all the wiring, verified voltages from the main panel, and so forth. I was able to get the breaker to reset, but only after I disconnected the line side neutral of the breaker (internal wire). However, when checking voltage in the spa panel i found this:
1) 240V line to line-both line side and load side of GFCI
2) 120v line to neutral and line to ground on the line side of the breaker
3) 38V L1 to neutral on breaker
4) 208V L2 to neutral on breaker
5) 85V ground to neutral on breaker

Now, i wasn't involved in the replacement of the first breaker but it sounds like a similar issue and at the very least I feel this is an uncommon occurance. I am looking for thoughts or insight as to why I would get the above readings? Just to be clear, with the white internal neutral of the breaker disconnected from the main neutral the breaker holds. Connect it to the main and the breaker trips.
 

ActionDave

Chief Moderator
Staff member
Location
Durango, CO, 10 h 20 min from the winged horses.
Occupation
Licensed Electrician
....1) 240V line to line-both line side and load side of GFCI
2) 120v line to neutral and line to ground on the line side of the breaker
3) 38V L1 to neutral on breaker
4) 208V L2 to neutral on breaker
5) 85V ground to neutral on breaker


..... with the white internal neutral of the breaker disconnected from the main neutral the breaker holds. Connect it to the main and the breaker trips.
You didn't indicate where you were getting the readings I highlighted. Load side of the GFCI breaker at the spa disconnect perhaps?

You have a bad neutral or a neutral to ground fault somewhere. When you disconnect the white wire on the breaker from the neutral buss you disconnect the internal electronics that allow GFCI to work.
 

MattS87

Senior Member
Location
Yakima, WA
Readings 3-5 were taken from the line side of the breaker to the internal neutral of the breaker. There is nothing connected to the load side of the breaker and as I stated everything coming from the main panel checks out perfectly
 

MattS87

Senior Member
Location
Yakima, WA
They were taken with the white floating. If the white is connected to the neutral bar the breaker instantly trips (again nothing connected to the load side of the breaker.
 

iwire

Moderator
Staff member
Location
Massachusetts
They were taken with the white floating. If the white is connected to the neutral bar the breaker instantly trips (again nothing connected to the load side of the breaker.

That is very odd.

To me obviously that breaker is (now) junk but what is the root cause of two GFCI breakers expiring in less than two weeks?
 

MattS87

Senior Member
Location
Yakima, WA
That is very odd.

To me obviously that breaker is (now) junk but what is the root cause of two GFCI breakers expiring in less than two weeks?

That is my exact thought. I've never heard of something like this nor can I find a similar problem online. Did a lot of research and it would seem to me that one of the lines is "bleeding" through to the neutral internally? A gfci breaker does have electronics inside (ct, amplifier, circuit board) but 2 breakers is odd. And they are Eaton so not some low budget manufacturer either.
 

MattS87

Senior Member
Location
Yakima, WA
I will add that as an unlikely cause, I swapped L1 and L2 on the line side of the breaker just in case some sort of surge or spike caused the GFCI to go bad
 

kwired

Electron manager
Location
NE Nebraska
That is my exact thought. I've never heard of something like this nor can I find a similar problem online. Did a lot of research and it would seem to me that one of the lines is "bleeding" through to the neutral internally? A gfci breaker does have electronics inside (ct, amplifier, circuit board) but 2 breakers is odd. And they are Eaton so not some low budget manufacturer either.

As you said there is the electronics inside that drive the GFCI protection components, they are connected from one line to neutral, your disconnection of the neutral leaves that module in an open circuit condition and is the reason it will not trip when the neutral is disconnected.

Did you have load side neutral disconnected when doing these tests as well? If not any neutral to ground fault in the load side neutral will still trip the breaker, but pulling the line side neutral disables the GFCI so it doesn't trip.
 

MattS87

Senior Member
Location
Yakima, WA
As you said there is the electronics inside that drive the GFCI protection components, they are connected from one line to neutral, your disconnection of the neutral leaves that module in an open circuit condition and is the reason it will not trip when the neutral is disconnected.

Did you have load side neutral disconnected when doing these tests as well? If not any neutral to ground fault in the load side neutral will still trip the breaker, but pulling the line side neutral disables the GFCI so it doesn't trip.

Yes, as I stated all load side wires were disconnected.
 

JFletcher

Senior Member
Location
Williamsburg, VA
How much distance from the main panel to the spa panel? A 50A spa panel is capable of running low and high jet pumps, recirc pump, heater, and lights - quite a draw - is it possible the spa is causing a voltage drop causing the breaker to trip? The 40A main is a regular breaker and not tripping, yes? Perhaps as a test, use a standard 50A breaker at the spa panel long enough to get amperage and voltage readings at the spa with everything running. Second idea is that there is a fault in the wiring from disco to the spa, maybe something got nicked in the pull.

Is this a straight 240V spa with 2 hots and ground from disco to tub, or is there a neutral there as well? Not sure from reading which you have (it's early, havent had my coffee yet).
 

MattS87

Senior Member
Location
Yakima, WA
How much distance from the main panel to the spa panel? A 50A spa panel is capable of running low and high jet pumps, recirc pump, heater, and lights - quite a draw - is it possible the spa is causing a voltage drop causing the breaker to trip? The 40A main is a regular breaker and not tripping, yes? Perhaps as a test, use a standard 50A breaker at the spa panel long enough to get amperage and voltage readings at the spa with everything running. Second idea is that there is a fault in the wiring from disco to the spa, maybe something got nicked in the pull.

Is this a straight 240V spa with 2 hots and ground from disco to tub, or is there a neutral there as well? Not sure from reading which you have (it's early, havent had my coffee yet).

Main panel to spa is 20 feet roughly and thats correct the main 40A breaker does not trip. I took amp readings when I originally wired the hot tub with everything and read 32A on L1 and 27A on L2.

A nick in the wire is extremely unlikely since I actually was able to push the wires through the conduit (roughly 10') instead of pulling them with a fish tape and there are 4 wires total
 

kwired

Electron manager
Location
NE Nebraska
Maybe check integrity of the supply side neutral? Open neutral condition maybe has had enough voltage issue to damage the electronics of the GFCI?

Or some transient voltages were a contributing factor? (seems a little less likely to happen more then once in such a short period unless something more obvious is the cause)
 

ActionDave

Chief Moderator
Staff member
Location
Durango, CO, 10 h 20 min from the winged horses.
Occupation
Licensed Electrician
Readings 3-5 were taken from the line side of the breaker to the internal neutral of the breaker. There is nothing connected to the load side of the breaker and as I stated everything coming from the main panel checks out perfectly
Odd indeed.

I would try unhooking the hot tub, use regular breakers and put a load, maybe some 240V baseboard heaters, on the circuit and check Voltage and Amps again.
 

kwired

Electron manager
Location
NE Nebraska
Odd indeed.

I would try unhooking the hot tub, use regular breakers and put a load, maybe some 240V baseboard heaters, on the circuit and check Voltage and Amps again.
Be sure to mix some neutral load into your test load - especially if the tub has neutral load.
 
Status
Not open for further replies.
Top