There are basically two ways noise can be propagated , airborn(inductive coupling) and through the system wiring, the step and direction signals are probabally 5v and the VFD output is 240v ac with spikes possibly higher.
There are two schools of thought on the power supplies grounding, personally I prefer to set up a copper ground plate connected to earth ground and take the shields and all the suppy commons back to this plate. This way I feel I have some control over the noise issue , if the various supplies are floating, and I have a noise problem, where do you start?
I have had only one problem that gave me aggravation and that turned out to be my fault on missing one encoder shield.
Al
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CNC, Mechatronics Integration and Machine Design.
“Logic will get you from A to B. Imagination will take you everywhere.”
Albert E. |