Now that I am actually getting into my electric build be prepared for lots of questions in here. I am running 240v 30 amp GFCI for my system. As far as power is concerned I know that for 240v that I need 10 gauge wire, and for the 120v leg I only need 14 gauge wire. Now everything is 10 gauge all the way to my brewing control box. But do the ground wires inside my brewing control box and beyond (to my heating element and March pumps) need to follow those same guidelines?