I have to hook up a piece of equipment that is 3 phase 220 volt and pulls 22 amps ,problem the circuit that runs by it is in 1 inch EMT and has 16 #10 thhn wires in it 3 of which are suppossed to go to the equipment .This run is also roughly 250 feet long ,am I correct by looking at the derating chart and at 10 - 20 conductors I derate to 50 percent and can only load 15 amps on these wires ? or am I only allowed 80 percent of the 50 percent which would be 12 amps ? not for sure which it is but have 1 red wire that is being used for a grounded conductor or a neutral
