As an electronics engineer, the CNC router table build has been fun...no noise at all well shielded wiring everywhere.
I ran into an issue with a shorted E-STOP cable not letting a second in series switch operate correctly.
The second switch I'd put at the other end of the table worked fine, but not the one right in my main control box. (????)
I'd apparently crushed the wire on the second switch and the ground (making it look like it was still closed) was the ground from the table back to the elec box. The table was grounding the wire in between the two E-STOP switches.
Now here's the fun part.....
The only ground the table has back to the control box and back to the power mains, was the added ground wire I'd put in the Chinese spindle! Yes my table was that well wired.... the only ground was through the VFD back to the power mains earth terminal, which of course was wired to my control box chassis.
So... my question...... with everything shielded, even have chokes on my Spindle power cables..... earth grounding the table metalwork directly to the power mains earth like the control cabinet and electrical breakers box, and removing the 'added' spindle ground wire inside the spindle, am I creating a scenario for a major leakage path?... a charge getting built up that might later break down insulation somewhere creating a problem?
The spindle power cable is shielded 4 wire conductor. The 4th wire (added ground connection at the spindle end) asnd the cable sheild are tried to earth ground at the VFD, with that same terminal going back to the breaker box mains ground.