George:
I can add a little from personal experience..
Did a printing plant move back in mid-80s..
Had some equip from early 40's that was DC. We installed a rectifier and "DC" rated panelboard. I kept all DC in sep. conduits.
Doing a walk thru at the old loc. in NYC, the Shop Foreman showed me some DC tools he had/used. I asked where he plugs them in...he shows me normal 15 amp, 120 volt 3 wire receptacles by his bench...I ask, how do you know which are AC, and DC......????
He replys 'experience'
I installed a non-NEMA oddball twistlock for all the DC 125 volt 'toys'....
John
