Normally on a large gantry with a cable carrier there is not alot of choice but to run motor and control together, as long as all cables, including motor feeds are twisted together.
It would pay to run low level limits switch conductors in shielded cable, it can pay to adopt the industrial control method of using a higher voltage, 24vdc for example.
make sure you take a good ground conductor to the gantry and motor frame.
Steppers are usually low impedance devices and radiate more than pick up noise.
Al.
CNC, Mechatronics Integration and Custom Machine Design
“Logic will get you from A to B. Imagination will take you everywhere.”
Albert E.