pwm schematic help required please?

[Jools]

If you measure voltage across the middle and right hand pin on the POT this should go from zero to 5v (or what ever the voltage in is) The missing central wire from the pot is the variable part of the voltage that controls speed. I would think that this should be wired up to your wire four from previous posts.

On mine I simply took out the pot and wired the PWM 10v in to the right hand pot connector (wire 1) (So I took my power from the machine) . The left hand ground to ground (wire 4). and the wiper to wire three. This controls mine perfectly.

Page 8 from this BOB manual helped me http://cnc4pc.com/Tech_Docs/C11GS-R1_1_USER_MANUAL.pdf though your's might differ. Though it may be the same.

This is my BOB's wiring digram though it was the same to my machine not using a VFD as they show.

Jools