We, meaning Myself and some fellow electricians at the mill site are debating this question. Insulation is all the same.
Is the control circuit considered a class 1 remote control circuit? I say;"Not if the control voltage is an extenision of the power system"[ i.e." the transformer is fed/tapped from the 480v line.]
This industrial facility has some rules that they are following and i am not sure where they come from, some are NEC,Some are NFPA79, and the others are from ??
No more the two motor T-leads in a conduit
Separate out the control [PLC,low voltage, class 1,2,3 from the t-leads], in this case the PLC is 120volts
Art 725 says class2, class3, conductor must be separated from and not occupy the same race way, but unsure of class1 conductors?