Jrk 12v12 'no power' not detected

I have a set-up using two jrk 12v12 activating two motors using analog voltage feedback mode each with 10k potentiometer for position control.
One of the jrks don’t report the ‘no power’ error. Any idea why that may be?
Both are connected to a 12v 30Amp power supplies each. Both running firmware version 1.4
The same jrk with this issue also has a ‘scaled feedback’ issue, meaning that the reported value varies about 800 units with the motor stopped (no position change).
Already did a firmware reset/update and the behavior didn’t change.

Thanks in advance for your support!


Could you clarify what you mean when you say that one of the jrks doesn’t give a “No power” error? Is the problem that one of the jrks is reporting a “No power” error while you have power connected or is it that one of them is not giving the error even when power is disconnected?

How long have you had the jrk that is behaving strangely, and has it always had this behavior? Could you post some pictures of your setup including all of your connections? Could you measure the output of your potentiometer to make sure it is functioning properly? Also, if your two setups are identical, you might try saving the settings file from the jrk in your working setup and loading it onto the problematic jrk. You might also try swapping the jrk controllers to test the problematic jrk in a known working setup.


Hi Brandon,
I meant that it doesn’t report the error when it is not powered, whereas the other JRK does.
I don’t remember exactly if it behaved like this from the very beginning or if the behavior occurred at some point.
I’ll try to replace it with the other to see if I get the same behavior, eventually at least trying the other power supply.

I’ll get back to you on this.
Meanwhile I solved the issue with the feedback. It was a wiring problem involving the potentiometer.