Hi,
Was the cable from the VFD screened?
No. Don't need it. It was only that I laid a sensitive cable up against it that I had trouble. As soon as I shifted it the
noise problem went away.
I have found the most pernicious of noise from a VFD is not the output to the spindle, not that it should be discounted
or ignored, but the harmonic distortion the VFD creates on the incoming AC supply. That same supply is used for the PC
an other electronic power supplies. Harmonic distortion created by the VFD is inclined to be conducted through the other
power supplies. The frequencies of the harmonics are typically 150z to 5000Hz, and are a real PITA to filter out.
To this end I use a line reactor of about 6mH on the input to the VFD. It greatly improves the power factor of the VFD
and greatly reduces the harmonic distortion of the AC supply. Single best noise abatement strategy I've ever used.
Craig