I have a 800 amp 277/480 volt mcc panel running a small plant,in the same room with the mcc panel i am adding a 30 kva transformer 480-208/120 for a subpanel,out of the mcc panel,i tapped the main nippled out of the mcc with a galv.nipple bond bushing on each end to a 40 amp disconnect, i ran 4 #8 3ph and a ground. in 1" sealtight with bond bushings on each end, i ran 8'to the transformer 3ph and the ground that is connected to the transformer frame. out of the transformer to the sub panel with 10' of pvc with 4 #2 AND 1 #6 ground, bonding done in the subpanel, #6 grounding electrode to plant steel frame.
