i installed a gfic 50amp in a sub panal box ..i have 4 wires coming from my main panal to the sub.. the black and red go to the top of the gfi and the white goes to a bar,the pig tail from the gfi goes to the same bar.. and the ground goes to a different bar....coming out of the gfi is a red and black wicth goes to my hot tub and a ground ,my tub does not uses a white neuter.. is this hooked up right