hot tub tripping gfic breaker???

[charlie tuna]

i have a friend who bought a house with an existing hot tub on the porch that is tripping the gfic breaker. here's how it is setup. next to the 150 amp - 2 pole main breaker sets a 60 amp - 2 pole gfic breaker which feeds a eight circuit panel at the corner of the house near the hot tub. in this panel is a 2 pole 50 amp standard breaker which feeds the hot tub power panel via an underground pvc raceway. this hot tub requires a neutral because the circ pump and controls require 120 volts. the only thing needing 240 volts is the water heater. he says the gfic breaker trips as soon as the circ pump comes on which is interlocked and brings on the water heater. i don't mess with these things--but shouldn't it be either "all" 120 volts or 240 volts?? the feed has full size neutral and ground along with the two hot legs.. about ten years ago i ran into this same problem -- but can't remember how we solved it?? can one of you guys give me some pointers??? thanks, charlie tuna

 

[pierre]

Re: hot tub tripping gfic breaker???

Remember that GFCIs trip on leakage current as well as a ground fault. If the panel and the other items have almost enough leakage current and then the pump pulls in, maybe the combination of all the circuits is too much leakage current.

How long are the conductors? Long runs will probably be too much leakage for the GFCI breaker.

 

[james wuebker]

Re: hot tub tripping gfic breaker???

Charlie Tuna, It sounds like in the first and second sub panels the neutral and the grounding wires are tie together in each box. They should be separatored after the main 150 amp box. It sound like the your getting a parallel path back on the neutral and grounding wire which is causing the GFCI breaker to trip. This is just an idea.
Jim

 

[charlie tuna]

Re: hot tub tripping gfic breaker???

jim,
the neutral is made up in the 150 amp service panel and runs all the way to the hot tub. the ground is made up on the main ground bus in the 150 amp service disconnect and goes to a ground bus in the subpanel at the corner of the house and of course then out to the hot tub. the neutral off the gifc is also made up on the 150 amp service disconnect neutral bus. from what i've been told. the gfic breaker will allow different loads on the phase legs --correct? because the pump and controls are 120 volt and will create an imbalance. i'm thinking if the gfic is sensing current returning on the ground wire (?) i could disconnect the ground to see if it doesn't trip...... this way i know there is a ground somewhere in the hot tub --whatcha think?

 

[charlie tuna]

Re: hot tub tripping gfic breaker???

pierre,
the distance from the service to the subpanel is about thirty feet and then maybe twenty feet to the hot tub!! thanks, charlie tuna

 

[charlie tuna]

Re: hot tub tripping gfic breaker???

there is some information from the gfci manufacturer that the 2-pole 60 amp gfic is not designed to operate on a four wire system.. this is beginning to tell me that the only way this system will work is for everything to be connected to 240 volts--ie. no 120 loads??