Messages

231

General Mach Discussion / spindle calibration help

« on: November 08, 2005, 01:13:55 PM »

Anyone have any experience with spindle calibration.  I am using the PWM mode to fire a mosfet that charges a capacitor and feeds a voltage to my Sieg 7X12 mini lathe.  I know that my voltage to PWM signal is probably non-linear and thought the spindle calibration would change the gain for the output of the PWM signal.  When I run the auto calibration it goes through it completely and finishes but the graph and operation of it looks erratic, the graph of control output and speed moves even though the speed is not changing and the control output is not changing either until the last few minutes, at that time the graph is pegged out and the control signal changes so fast the motor accelleration never catches up with it.  Is there a way to manually enter the curve if I manually plot the PWM output vs speed.  My circuit works fine and I can change the speed just fine, just would like to fine tune this.

Thanks Zar

232

General Mach Discussion / Re: spindel speed pulse count setting

« on: November 08, 2005, 01:01:57 PM »

Bill,

I think the program does this automatically but you have to have one of the pulses or slots 50% larger than the others.  I think it sees the pulse width of the large one and uses it as the index mark.