DMX Termination in OneTrack by ETC

Can I terminate DMX over Cat5 on OneTrack by ETC?

No. 

The Onetrack by ETC DMX terminator uses screw down terminals which are not acceptable for Cat5 wiring.
Instead, you may terminate the Cat5 cable to a D60XTI DMX term kit (p/n 7410K4012) to convert this data line to Belden 9729 equivalent wiring.  

Can I terminate power and DMX in the same end feed?

OneTrack by ETC requires power and data be installed in separate feeds, as required by NEC.