I recently installed a Flag pole at my home and ran a UF electrical wire to an exterior outlet, on a GFI circuit, to illuminate the flag at night. This GFI circuit controls all of the outlets in my garage as well as all outlets which are installed on the exterior of the home. Once I attach the UF wire the GFI immediately trips. I currently have a spare refrigerator, irrigation system, and FIOS cable on this same electrical line. I'm looking for suggestions on how I can get this to work.

Thank You

Determine if a particular device is causing the tripping. Particularly, the refrigerator.

Pull everything out. See if it trips.

Then start taking the string out in the middle of the run. See if it trips. Then put the circuit back and undo the middle of the section that tripped. It will only take a few iterations to find the problem.

First, exterior lighting does not need GFI protection. Optional.

It is probably a 100 watt metal halide, which uses a core and coil ballasts. These can have weak ground faults, as normal.


Or the distance of the cable can help with tripping on long runs.

So unless you really need the outlet, hardwire the fixture and eliminate the GFI.

Otherwise you can check the fixture for visual shorts, or try a new ballasts or better new fixture.