Question about breakers, subpanel, gfci

[kevreh]

Hi-


I'm planning on adding a Suntouch to my pool to replace the intermatics I have and automate the valve on my solar panels. The main circuit feeding my pools subpanel is 40amp. This is shared by my furnace, which is gas and therefore probably uses a small fraction of that 40amp. There's 240v going out to my pool panel (iirc the main and booster pump are hooked up for 240).

My current subpanel has three breakers; 1 for main pump (1hp), 1 for booster pump (3/4hp), 1 for 120v lights (gfci).

QUESTION.... When I install the Suntouch, I understand that I need to still have gfci. The recommendation in the manual is to go from the relays to a subpanel then to the equipment. To keep it simple I would like to have 1 main GFCI breaker. Seems to me that I can one of two things; install a GFCI in my main/house panel and nowhere else in the system, OR, install a GFCI in the subpanel downstream from the Suntouch. The first option is cheaper. Is one better than the other? With the 2nd option I won't be able to have just one gfci breaker, I would have to get one for each pump and the pool light. ?

A 3rd option, mentioned in this link (wiring-question-upgrading-to-a-suntouch-controller-t42815.html?hilit=suntouch) would be to have main power come into subpanel (1 main gfci breaker) THEN power to the Suntouch and the pumps from there.

Thanks,
Kevin

 

[bk406]

You want to put a GFCI breaker on each piece of equipment you need to protect. Putting one in the main to protect the whole sub panel is not the correct way to do it.

 

[kevreh]

Thanks bk406. When you say "not correct" do you mean as a best practice or not code? Also, whats the disadvantage? The voltage from the different devices causing false gfi trips?

 

[bk406]

Well, a little of both, really. Code says the pool light and the pump needs to be on a GFI/GFCI protected circuit. That would mean, if you read the letter of the code, protecting the entire panel wouldnt be correct. Even if it somehow passed inspection, it's not best practice either. If the pool light encountered a situation were it needed to trip the GFCI breaker, there could be an issue since the GFCI breaker would be in the main on the entire 240 volt feed. Again, its just not good practice to do it that way. Buy the breakers you need and do it the right way.