I previously ran a 50a circuit for a spa and it had no place for a neutral at the spa end, so I did'nt run one. I put in a 50a GFI breaker (not using a neutral) and tested the GFI hot to ground on both legs at the spa and it worked, the GFI did trip fine. Was I wrong for not running a neutral? Even though it trips ok? I'm not sure why this works since GFI's use the neutral and ground.