Lead cnc with Nema 23 motors, Arduino Uno R3 controller, Mean Well power supply and VFD. Have this setup for nearly a year now and all was fine until today when I went to start a carve and the motors/axis started to thump/judder and move slightly. I managed to track it down to the fact that all was ok until the VFD was powered up and spindle was spinning. Turn off the spindle and motors stop juddering. All wires are shielded. Checked the electrics and cannot see anything amiss from the previous day when all was fine. Help
Somewhere a ground wire has come loose, not visibly 'off the terminal', but loose nevertheless. I would disconnect and reconnect every wire on the VFD (both ends) and then test. IF there is a still a problem after that, do every other wire as well, unplug/replug every plug and undo/redo every screw terminal, including the ones on plugs if they exist. Unplug/replug the AC cables too, this scrapes the brass terminals and refreshes the connections.