Thread: pwm numbers
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Unread 15-03-2004, 01:15
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Re: pwm numbers

From page 18 if the 2004 Programming Reference Guide :

Quote:
PWM Speed Controller
Full Forward = 254-227
Neutral = 136-123
Full Reverse = 0 - 37
So there are your full speed and nuetral numbers. I don't know if calibrating the speed controller changes this (I hope not). I believe the Victor 884 speed contorller varies the duty cycle (percentage of time motors recieve 12V, the voltage "averages" out over time) linearly between these values. So 181-2 should be 50% duty cycle or half speed (averages to about 6 V, I really should scope this).

It ultimatly depends on the motors you use and thier partcular torque-speed curves. I have noticed that the CIM motors have low end torque issues. When given low pwm values they have a tendency to simply stall. For example: if you use CIM and Bosch for drive motors, you probably will notice the Boschs moving before the CIM motors. We used a program fix for this last year.

Well I guess I was a little too thoeretical I sorry about that. Hope it helps. Good Luck
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