Sounds to be an internal short on the transformer. If you are handy with the multimeter--you can remove the secondary wires that is providing power for the logic board and test there.. This can help determine where the problem is.. I did find the manual here--but it is just the basic one-- http://www.parpool-spa.com/Page/Help/Te ... g-MS10.pdf

Thanks for the quick response. The weather has prevented any further testing (or swimming!) for today but I'll start there. I suspect you may be correct. Does anyone have a source for parts?

On another note, my pool installer had the unit hot wired to be always on yet the manual says it should be connected to a timer so the SWG is only running with the pump. Any comment about that?

Sounds like the installer is using the flow switch as an on/off switch for the MS-10 --this can be a bad thing --if the switch fails and tells the unit to produce when there is no flow from the pump.


here is a list of common parts and prices--may not be the best prices --but least it is a start.... http://www.poolpartsonline.com/p-659-aq ... parts.aspx

Once again, thanks for the quick response. First I isolated the transformer and the breaker still tripped. Then I completely disconnected the panel and got the same results. I concluded it's a ground fault somewhere in the circuit. I tapped into another 110v GFI circuit going into the panel and the SWG is once again working. Looks like I dodged a bullet this time around. (I didn't like those part prices!!!)

So with "no flow" the SWG turns itself off automatically? My next project will be to connect a timer to generator