Re: Jonboy's Pool Light Tripping GFCI

[jonboy]

I also have a Pentair light: "Amerlite" ig pool light, 500w, 120vac. It was working fine until:
I noticed the pool supply panel was not protected by a GFCI, so I installed a new GFCI breaker in place of the breaker that supplied the pool panel. The pump fed by that panel works fine, the outlet fed by that panel works fine. But, the light trips the GFCI immediately when I turn it on.
I disconnected the light at the box about 6' from the pool, turned the light on, and it did not trip, so I know its not in that section of the wiring between the supply box and the box by the pool.
I took the pool light assembly out onto the deck to visually inspect it and it had no water or vapor, that I could see, inside the assembly, but still tripped the GFCI as soon as I flipped the switch (no flash, nothing, immediate trip).
I measured the resistance as suggested, and it measured 500k-600k ohms across the green to white, and across green to black. It measured 0 ohms across the black to white. I then took the bulb out and got the same measurements across the green - white and green - black, but infinite resistance across the black to white.
I considered a faulty bulb, so I replaced it with a regular household bulb (60w). It tripped immediately.
Do I just need to bite the bullet and buy a new light assembly? Please tell me I'm overlooking something.