Eaton 50A GFCI Tripping Intermittently

[MisterMoSparky]

I went to the homeowners house that needed a 50A 120/240v circuit ran for his hot tub. The Meter Disconnect Combo was located near the hot tub so the hot tub company agreed that I could just run the circuit straight from the meter combo. I ran Black, Red, White 6AWG THHN and 10AWG Green equipment ground to the hot tub and placed on 50A Eaton GFCI Breaker. The pigtail for the breaker is connected to the neutral bar/ground bar since this is the first main disconnect and they’re bonded. The Hot Tub came wired up 120V, hot tub company removed cord and plug and also the jumper inside the control board. When I go to turn on the breaker at first it was instantly tripping the GFCI, then one time it held for several minutes no problem. I went to put the meter cover back on and accidentally pressed the test button. Went to reset the breaker and instant GFCI trip again. I disconnected the wiring from the hot tub and discovered no issues when resetting the breaker. I left it off and put all the covers on and told homeowner to have hot tub people trouble shoot the tub. I tested continuity on my wiring and it was open on all combinations (except ground to neutral obviously) but I tested neutral and ground separately and discovered no resistance either (open circuit). Hot tub guy comes out with me standing there and flips breaker on no problem, tests the GFCI and resets no problem. I put the cover on thinking everything is fine when the breaker trips again. Mind you no arcs or anything during any of the trip events except for when I put a GE GFCI breaker in. This arc happened inside of the meter. I also tested resistance on the actual lugs of the hot tub with the wiring disconnected and found 38 OHMS from L1-Ground and L2-Neutral? I installed the Eaton GFCI again and I found out that barely pushing the wires back in the cabinet would cause it to trip. Eventually I zip tied the wires back in the cabinet and put the cover on made sure no wires were touching and there was no damage on any of the insulation anywhere. Reset breaker and everything is fine now. I even moved the liquid tight conduit coming out of the meter some to see if I could get it to trip again and I couldn’t. I’m at a loss of words with this one, I reassured the homeowner that the GFCI is doing it’s job hence the tripping and I gave him my personal number to call me if he has any more issues. Me and the hot tub guy quadruple checked every possible situation that might cause an issue and checked to make sure the GFCI would trip by touching the neutral and ground together in the hot tub. Overall everything is working now but any thoughts as to what happened?

 

[MisterMoSparky]

Pictures of Meter Combo and Hot Tub Panel

 

[Wgardne]

Late to the party here. Actually created an account to reply here. Ran into something similar. New hot tub install. Brand new hot tub. Brand new circuit ran and brand new Eaton gfci spa disconnect. Tripping intermittently. After talking to supply houses, spa manufacturers and Eaton, there is a known issue with hot tubs and Eaton gfci disconnects. Eaton is aware of it, the supply houses I use have heard the same stories. Not sure what Eaton is doing about it but I’m steering clear of Eaton disconnects now. Put in a square d one and customer hasn’t had any trips at all.

 

[Little Bill]

There's no telling how many Eaton Spa disconnects w/GFCI I have put in. I've had zero trips from any of them. I haven't put it one in a while so they may have changed something.

 

[hillbilly1]

I had an Eaton 60 on mine, never had an issue. Sounds like it might be a heating issue, leakage from the heating element failure is common.

 

[tortuga]

.... /no arcs or anything during any of the trip events except for when I put a GE GFCI breaker in. This arc happened inside of the meter. I also tested resistance on the actual lugs of the hot tub with the wiring disconnected and found 38 OHMS from L1-Ground and L2-Neutral? I installed the Eaton GFCI again and I found out that barely pushing the wires back in the cabinet would cause it to trip. Eventually I zip tied the wires back in the cabinet and put the cover on made sure no wires were touching and there was no damage on any of the insulation anywhere.

I suspect in the OP's case there is a slight manufacturing defect on the circuit board, such as a loose solder joint or moisture in the titanium sheathed magnesium oxide (MgO) heater element. Magnesium oxide is hygroscopic, meaning that it likes water, and if moisture is present current will leak thru it to the sheath, this is often the case with a new electric range tripping a GFCI.
With older spa's that are tripping GFCI's 99% of the time its the heating element. Typically I disconnect the heater element from the board and check it with a megger, element lead to equipment frame ground. Megohms should be in the range of ~500 megohms. A low reading means the element might be leaking current to the frame and into the water.

 

[ptonsparky]

I vote for a new circuit board. Bad when it came or broken when connected and powered up.

 

[hillbilly1]

I vote for a new circuit board. Bad when it came or broken when connected and powered up.

Could be, looks like they are using a printed circuit board instead of a hard wired contactor to power the heater.

 

[g-and-h_electric]

Megger or ohm out the heater first. I have had a hot tub here for since 1988 ( on the 3rd one (dont ask about the second one)). Cant tell you how many bad heaters I have had . I did have 1 bad circuit board and yes, it was the heater relay that burned up the board.

I would still start with the heater .

Just my 2 cents worth.


Howard