I'm putting together the controls for a CNC router table I'm building. In the enclosure I've got some DIN rail power supplies, contactors, and terminal blocks.
Also in the enclosure is the VFD for the spindle and the computer interface electronics.
The power supplies supply +24 V (computer interface, sensors, and fans) and +75 V (servo power). Should the negative (0 V) rails be tied together and to ground (and the chassis)? I don't mean using the chassis as a conductor, there are return lines for everything. But should they be tied together?
Is there a typical practice for this in industrial control systems? I'm inclined to tie my 0 V rails together (so everyone’s referenced to the same voltage), but not tie that to chassis ground.