Chinese Spindle Issue
 

This is just a heads up to anyone else who comes across this problem. My 3kw air cooled Chinese spindle has run reliably for 3 years until a couple of days ago when in the middle of a rush job it stopped spinning. It was making noise and varying the frequency would alter the noise but the spindle was only making feeble efforts to turn. I was all set to order a new spindle but delivery was going to be about 10 days for a reasonably priced one. I had checked all my wiring for continuity but as a last resort I dismantled the connector on the spindle. It turned out one of the wires had worked loose as they only use screw terminals.

Just to add my comment. I changed the connector and found that grounding pin is not connected at all - 3kw air cooled spindle.

Milosh