30hp at 40FLA so 125% gives 50Amps
20hp at 27FLA so 125% gives 34Amps
AWG #3 THHN is 110 Amps
AWG #8 THHN is 40 Amps (but according to the astric it can only be 30 Amps)
AWG #6 THHN is 55 Amps
So looking back over everything you are right the 10 would be to small, so it looks like #3 and #8...
the motors are running two different conveyors, although the motors are side by side. They are controlled by two independent controls. They may or may not run at the same time it is according when they are needed.
I need a little help with my wire and conduit sizing. I have a 30 & 20 hp 460V motors close to each other and wish to run the wires in the same conduit. Both motors are less than 30ft from the starter (20hp) and VFD (30hp). Would a #8 and #10 wire be the correct size for the 30hp and 20hp...