hey folks, i am wiring our tub and have done it succesfully so far. the tub is a blue ridge and is a 240 volt based on the wiring diagram choices i have. they are 120v, 120/240v, or 240v. the circuit board has no neutral terminal so it is the 240 volt.

i have the main panel equiped with a 50 amp double pole breaker, using 6awg wire in pvc conduit to the gfci disconnector box. wired accordingly inside the gfi box, and the pigtail attaching to the neutral buss bar. my question is this, in the gfi box, the neutral buss bar has 2 bigger lugs, and a couple smaller holes. the one big lug is for the neutral from the main panel, and the other is labeled as "equipment ground". just curious what this is for, as there is a ground buss bar in the gfi box that has a ground direct from my main panel, and then off to the tub ground bar. the tub is bonded to the ground bus bar also. thanks for your help. i could not find the info here and my eyes are blury from reading so much