Trouble limiting current with jrk 12v12 motor controller

I’ve been using a jrk 12v12 motor controller to drive a windshield wiper motor, with great success. It worked very well, and never pulled too much current. But the motor was a little too light, with a poor shaft interface to work with.

So I bought a heftier motor with a stronger shaft and gearbox. But that does not work as well. I had the current limit set at 15 Amps, and it got triggered. I boosted the current limit up to 29 Amps, and no longer get any current limit errors.

But I do sometimes get Error 0.0004 Motor driver error. That happens even when the motor is moving normally, far from stall current or startup surges. And the controller seems to be getting hot, even though I’ve tried to monitor (using the JRK Configuration Utility) the continuous current being drawn and it seems to be below 10 Amps.

Could the “Motor driver errors” be caused by too much continuous current being pulled? What else could cause those errors? As mentioned, they do not happen when a lot of current is being pulled in a surge. Quite the opposite. They happen as the motor is running normally.

If the new motor is just too big for the jrk 12v12 motor controller, do you have any suggestions? I use the feedback feature and the PID tuning. Your motor controller is very nicely done. I don’t know what I’ll be able to use as a substitute.


Thank you for the compliments.

Yes, the motor driver error could be caused by a motor that draws too much current. In the “Error Reporting Commands” section of the jrk user’s guide, it says “The jrk 12v12’s motor driver fault occurs when it detects that motor output A is shorted to ground or VIN.” Whenever the VNH2SP30 motor driver chip on the jrk pulls its DIAGA or DIAGB lines low, the jrk reports that as a motor driver error, so if you are curious you could learn more from the VNH2SP30 datasheet.

Do you have a datasheet for the motor or some independent way of measuring the current it draws? The Plots window of the jrk configuration utility can show you the current draw, so it would be good to look at that too. (Just click on the graph in the upper right corner, check the ‘Current’ checkbox, and change the scale to something like 20000 mA.)

The motor driver error is an error that the jrk can automatically recover from, so maybe that would be good enough for your application. If the setting for “Motor driver error” in the Errors tab is set to “Enabled & Latched”, try changing it to “Enabled” so that the jrk can automatically recover and keep driving your motor.