Can a GFCI breaker feed a sub panel?

(system) #21

Hi,
Great idea - one big problem though, hopefully you can solve it for me…

I found this topic and tried it - and it worked perfectly! I needed a 20 amp 220 GFCI for a jacuzzi in a new bathroom. Such a device was $350. I found a new sub panel that came with a 220 50 amp GFCI in it for $35. Put the 50 gfci in my main panel to feed the new sub panel and put a $10 20A in the sub panel to run the tub.
Tub works great.
Later, I needed a new 110 circuit and thought I would use one of the extra slots in the new sub panel. No joy. The new circuit trips the 50A GFCI.

I suspect it may be because the 220 20A for the tub users 2 rails and the new circuit is 110 using only one rail.

Could this cause a return I’m balance that is causing the trip?

Any way to fix it?

Thanks.

(system) #22

Hi,
Great idea - one big problem though, hopefully you can solve it for me…

I found this topic and tried it - and it worked perfectly! I needed a 20 amp 220 GFCI for a jacuzzi in a new bathroom. Such a device was $350. I found a new sub panel that came with a 220 50 amp GFCI in it for $35. Put the 50 gfci in my main panel to feed the new sub panel and put a $10 20A in the sub panel to run the tub.
Tub works great.
Later, I needed a new 110 circuit and thought I would use one of the extra slots in the new sub panel. No joy. The new circuit trips the 50A GFCI.

I suspect it may be because the 220 20A for the tub users 2 rails and the new circuit is 110 using only one rail.

Could this cause a return inbalance that is causing the trip?

Any way to fix it?

Thanks.

(system) #23

I’ll start by saying I’m not a trained professional …

If your 50A 2-pole GFCI breaker is tripping every time that you use the 1-pole circuit in the sub panel then I would expect that the load neutral isn’t connected through the 50A GFCI breaker. Per haps I’m stating the obvious here. If you us a 2-pole GFCI only to power 2-pole 240VAC loads, then you don’t have to connect the neutral through the breaker and can attach directly to the neutral bus. If the breaker will feed 1-pole 120VAC loads, then the neutral has to be connected through the GFCI breaker or it will trip every time you activate the circuit.

If it only trip when you have both the tub (240VAC) and the 120VAC loads turned on, then it may just be that the sum of the leakages exceeds the 6mA that trips the GFCI. I suspect this would indicate a problem with your load that’s worth investigating.

Dan