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DFZXA
12-02-2012, 18:17
I know that when using the motorcontrolsetoutput.vi that we can set the scaled pwm value from negative 1 to 1, but how exactly does that convert to the voltage that is being put out to the motor? Is there some equation for this or what? I'm basically trying to do this to try and control the speed of the motor. I know I could do this with CAN, but I don't have the wiring for it.

baronep
12-02-2012, 18:37
PWM doesn't actually change the voltage directly. It is just a signal to communicate with the motor controllers (Victors/Jags). Here is in explanation of how PWM works...http://en.wikipedia.org/wiki/Pulse-width_modulation

EricVanWyk
12-02-2012, 18:46
For a jaguar, a good first pass approximation is "applied voltage = battery voltage * signal (scaled 0..1).

A Victor is similar 0 and 1, but applies a larger effective voltage than expected in between.

For both, don't forget about the resistances involved.

DFZXA
13-02-2012, 11:02
Thanks to both of you. I understand it a lot more now and I'm sure I can do it.