the PD002 setting did the trick o.k. i can at least turn the spindle on/off( kind of ) from F5 . i can also increase and decrease the speed but i still need to have the active low setting ''ticked '' for the start / stop output. the spindle still runs on its own albeit at a very reduced speed . i have an LED on board the BOB for the relay outputs and the relay for the ''start /stop '' is constantly on because of the active low tick. It looks like a synchronisation issue between MACH and VFD, i think. ??? if there is such a setting . i also set the spindle pulley tab to ''MIN ZERO'' & ''MAX to 24000'' . there must be some other setting i'm missing. cheers jazz.