twisted pair or shielded cable for steppers

In the film scanner I'm modifying, which is a rather large beast of a machine, there are stepper motors, relays and sensors all over the place. The original design had mostly shielded cables, which were bulky and are custom made lengths. Since I'm rearranging and changing a lot of the internals of the machine, a lot of these cables won't work for me - they'll either be way too short or way too long. Also, they use funky quick-connects, which are nice but not easy to take apart and reconfigure.

So I'm toying with a few options for the wiring of the sensors and motors. One is to use similar shielded cable and attach my own connectors (probably DB9 or something similar). The other, which I think would be cleaner, would be to us RJ45 connections and standard ethernet cabling. This is appealing because it's less bulky and will be easier to route.

Is one better than the other for an application like this? I'd imagine the longest length would be somewhere around 6 feet, and the shortest probably about 12 inches. I think my concern would be signal integrity, with the sensors and motors. Or am I overthinking this?


Shield the sensor cables if you can, twisted pair for the motors will reduce emissions from them, but you must twist the wires for each winding separately (I'm assuming bipolar steppers).

Shielded twisted pair would be ideal for motors of course.

And most importantly keep sensor cables separate from high-current wiring, don't run them side-by-side.

So maybe I'll use high quality STP Cat6a for the motors, and re-use the existing shielded cables (cutting down the too-long ones) with new connectors.