12-V-12 in PWM mode

Hello, I am using a 12V12 motor controller using a PWM input coming from an Orangutan SVP 1284. I have been using this same set up for some time quite reliably. I am not sure if a firm ware upgrade has caused the PWM mode to be unstable? If I use either the analog or serial inputs I get excellent motor control, when I use the PWM mode the control is quite jittery.

I tried a simple program to set servo “0” target to 1300. The servo will go to the proper position but I am getting momentary input errors (if I enable and latch the input error on the errors tab of the configuration utility it latches in immeadiately and will not clear, this is only in pwm mode, not the other two modes).

I also note that the communication to the device from the configuration utility is now very unreliable. It locks up and quits communicating on a frequent basis giving me a variety of “control transfer errors”

I have several motor controllers and they all behave the same. Any suggestions? Thanks


It would seem that it is a new motor in the project which is causing the 12V12 to operate eratically. I do not understand why I get an input error with the new motor but when I use the original one I return back to the stable performance. I am not tripping the over current protection on either motor.


It sounds like you are talking about one of our jrk motor controllers; is this correct? Is there a reason why you are using the RC interface rather than the serial interface? Using RC is relatively roundabout since you first have to use the Orangutan to convert a digital value into an analog pulse, which the jrk then needs to read and convert back to digital; sending the value serially is generally easier and more precise.

Since this change occurred only after a new motor was installed, I suspect you have a power issue or a motor noise issue. Also, if you are using PID for closed-loop control, did you update your PID constants when you changed motors?

Could you please tell me some additional information about your setup? How are you supplying power? What is the new motor’s stall current? What was your old motor’s stall current?