Pool installer from the 80s now pool owner from the present.

[kbjoga]

Spent 10 years in the 80s/90s installing pools. I ripped out a 40+ year old in-ground at my home and figured I'd get some ROI on my pool installation experience so I decided to put another one back in and am now getting ready for the electrical inspector to sign-off before pouring the deck (or at least I thought I was). I just upgraded the power to 20A GFCi breaker and am running an older (6-10 years) 1.5hp Superpump which runs perfect until I connect the bonding wire to the pump housing at which point the GFCI trips. I metered a 2V drop between my bonding wire and pump housing connection and am now wondering if I have a minor short in the pump motor that is causing the voltage difference between the pump housing and the bonding wire. I never really did much pump electrical troubleshooting in my prior role and was wondering if shorted pump motors have this symptom when connecting to the bonding wires? I can't recall having issues when opening pools for folks back in the day but it seems if this is a symptom of a bad pump motor others should have issues upon opening their pools and this should be a known problem.

 

[JamesW]

If you have a good ground wire on the pump, it should be causing the same issue as a bond wire. There must be some current leaking to ground from the power wires.

Shut off power at the breaker, disconnect the power wires from the pump and check the resistance from terminal L1 on the pump to ground and from terminal L2 to ground.

Check the resistance from one power supply wire to ground and from the other power supply wire to ground.

Don't do anything you're not sure that you can do safely.

 

[kbjoga]

Thanks for response. Not an electrician just an engineer. Been reading some old TFP posts which led me to realize and dig deeper into how I wired the 240V 2 pole GFCI breaker. I assumed the ground would act as the neutral so I wire it as such. Finding a 2007 post I discovered for 240V pump you don't have a neutral so you wire only the two power leads and the ground which I connected the main ground/neutral bar and you just simply skip the neutral. Everything is working as it should and now I can setup the electrical inspector then finally move on to pouring the deck - it's now a good weekend that I can enjoy.