Hi Doug,
I have encountered a similar scenario regarding GFI circuits. For the past 30 years our small town has hosted a large antique car, firetruck, boats, etc. outing (called WAMBO). I have been doing sound for their main entertainment (in a parking lot) for the past 3 years (2nd weekend in August). Power is provided at FOH in the centre of the parking lot, with the stage at one end and the beer tent behind FOH.
Last year they added the GFI to the power distribution and that is when I started having problems. Granted last year had a lot of rainstorms during setup/sound check and the shows. It got so bad on the Saturday show that the Chicago tribute band refused to continue the show until we could provide dependable power. The solution was to connect to a generator in an RV used for change room for performers located behind the stage. This got us though the rest of the show.
This last summer, I started having similar GFI issues but without the rain. I had requested that they provide me power (without GFI) to FOH and the stage. This was denied. The Friday show was frequently interrupted with GFI tripping. It finally dawned on me the next morning that the stage they were using (a flatbed trailer with risers in front) was the same one we were using for a weekly concert in another park and I never had any problems with the GFI there. The only difference was that I had setup my X32 Racks at the tongue end of the flatbed for the weekly concerts, but had setup one of my Racks at FOH (with a 250' AES50 cable, and power) for WAMBO. So for the Saturday show, I setup the same way I did for the weekly concerts and the GFI issue disappeared.
Paul Vannatto, Volunteer Forum Administrator and Moderator