I just added a PWM spindle to my machine (Mach3 > SmoothStepper USB > Gecko G540). Now it runs, but with some very odd symptoms:
- The spindle gets up to speed quickly (1sec?), but then slowly drops in speed... from 2500 RPM initially, down to <100, then stall, over the course of 2-3 minutes.
- If I check voltage across Ground->Speed pins at the spindle, I can watch it correspondingly drop slowly from 5V down until it stops, in tiny increments.
- Power cycling the spindle or Gecko G540 does not fix it.
- Stopping and restarting the spindle from in Mach3 does not fix it. In fact, if I stop the spindle, and restart it, it continues at whatever slow speed it was stopped at, and continues it's slow decline to stall.
- Changing the spindle acceleration in Motor Tuning of Mach3 has dramatic effects. A setting of 1 gives the "slow decline" behavior above. A setting of 5 causes the spindle to start, then stop within about 1-2 seconds. A setting of 10 causes the spindle to start accelerating and then decelerate to a stop before it even reaches full speed (<1sec), then it will do the same thing when the spindle is stopped in Mach3.
- Closing, and restarting Mach3, without turning off or resetting anything else, will reset the problem... resetting the spindle to its full speed, to start a new slow decline.
- Also, not sure if this is important, but I'm typing 2500 into the spindle box, Mach3 is showing 2500 in the sVo box, but the RPM box always shows less (~2415).
Anyone have any ideas?