Yes, I have all the info you say I need. I didn't post all the details because I don't want somebody else to figure this out for me. I just need to know how to figure it out for myself. But here are your answers:
Yes, the teacher designed the thing and put 16 conductors in the first section of conduit to the first panel. From there 12 go to the second panel, and then 8 to the next, and then 4 to the last.
It's 4-wire, 3 phase and the loads are all single phase so it is a current carrying neutral. 480V. I'm not giving away the distance to the panels or the current because I don't want somebody to post "The answer is X guage wire".
I understand that this wasn't designed to be built, it's just so we can figure out a wire size problem using voltage drop and conduit fill together. I just don't know how to use them together.
What I need to know is if I need to figure out the wire size using voltage drop and THEN make it bigger again according to the rules for conduit fill. Or if the bigger size wire because of voltage drop counts toward making it bigger for conduit fill.
If voltage drop tells me I need to use wire that would normally carry twice the current and conduit fill tells me I need wire that would normally carry twice the current, do I need wire that would normally carry twice the current? or do I combine them and use wire that would normally carry 4x the current?
