I found this little Video originally posted way back in Nov 2014, by Paruk, on the subject of Shield grounding at one end. I think it demonstrates clearly the importance of only earthing one end of the shielding. Enjoy
Cool demo I wish he would have demonstrated connecting both ends.. I think he didn't because it would not have made a ground loop. Ground loops happen when there is a difference in the ground potentials which you don't have when the same ground bar is used, even more so on the small scale of our cnc machines. Some of the comments correctly point that out. 15 years as an instrument tech (not that experience makes anybody an expert!), I've had ground loops be an issue once, it was on a ~50 meter long run for a pH probe, going from an electrical panel in a control room into a large caustic dip tank for metal cleaning. In-between those two things were many VFD's and robotic welders! The tank and the panel were not the same ground potential, would calibrate fine in a plastic cup, but once in the tank would drift a whole unit. At my last job, I worked with some brilliant electrical engineers (on large electric motion systems), and we used to have an inside joke that unexplained issues "must be ground loop".. Cheers Gary
