Quote Originally Posted by dachopper View Post
In the control box, I have main 220Volt house power earthed to the corner of the mounting plate, The Stepper Drivers are bolted to the plate, and the Torroidal Transformer is also bolted to the plate.
Then I have a single earth wire coming off that same corner to a small ACDC transformer, and another single wire that goes off then splits to 4 and is the AC earth for my woodchip / 2 x pond pumps and Spindle power inverter.

So I should earth the spindle + Spindle sleeve to earth in the inverter? or back to star?


From DC transformer - all that suff plugs directly into the stepper drivers etc....
OK some decent picture of your control box would be good.
You need to earth the screen at one end only.
Do you have screens on the stepper wiring?
Do you have the machine frame grounded?