A friend of mine owns a machine shop and she's attempting to install a few new CNC machines as well as switch all the voltages on her machines from 3 PH 240 to 3PH 480. She said that the utility asked her what size xfrmrs she needed on the new relocated pole outside of her facility. Assuming that she can change all of the voltages on her equipment from low to high, I'm guessing that her amperage draw will be reduced with the higher 3 PH voltage. How should I go about adding up the total loads and identifying the proper size xfrmrs for the utility company? I'm also guessing that they'll probably over size it anyway, based on what she asks for, right? Any help would be greatly appreciated.
