1/ All conductors carrying Low signals such as encoders should be wired with shielded cable, with the shield connected to earth ground at a central point.
And all parts of the equipment bonded to the same point.
http://www.automation.siemens.com/do.../emv_r.pdf?p=1
2/Most industrial electronics are generally built sturdy enough to stand typical vibration, if it is perceived to be excessive, the electronic assy can be mounted on rubber stand offs etc.
3/ There are a few manufactures of wiring carriers such as Igus etc, or non metalic flexible tubing can be used.
I also suggest you also get a copy of ANSI/NFPA79 if getting into Machinery Control Wiring.
Al.
CNC, Mechatronics Integration and Custom Machine Design
“Logic will get you from A to B. Imagination will take you everywhere.”
Albert E.