AC Wiring

[dks]

Question:I need to feed 5 combo gas packs and ac units and 1 heat pump on a roof.The ac gas packs are as followes #1 17 amp min ckt ampacity max brk 25 1 ph.#2 same as #1, # 3 25 amp ckt ampacity 40 amp max fuse 1ph.#4 30 amp min ckt ampacity max fuse 45 amps 3 ph.#5 25 amp min circuit ampacity max fuse 40, 1 ph. Heat pump 3 PH 81 amp min ckt ampacity max fuse 1oo amps.I want to feed this from a 400amp disconect located in the electrical room in the building.I propose to run this in 3 inch schd 80 pvc pipe, across the roof to a trough, and set my disconnects under the trough. All my units will be within site of its disconect but not within 50 feet is this OK ? I intend to feed my trough with 3 # 350 mcm with a #1/0 ground with no neatural, and fuse it at its source with 300 amp fuses.I have power on the roof to supply the gfic receptecals. Do they have to be no less than 25 feet from any unit? I will be feeding each unit from the trough with schedule 80 pvc is this ok? Any suggestions please reply. Thank you DKS