Hello + info req

hello all.

I bought the “Pololu Jrk 12v12” motor controller.

Just a little question:
I have a “12V 25A DC brushed 280watts winch motor”, can this motor be handled by my Jrk12v12 without problems?
(25amps at full work, but I want to use this motor with small loads so the amps will be 5-10)

And If i had a same motor but at 300watts?

Thank you!


The answer is likely to be no. It sounds like the 25A is just the rated current of your motor, suggesting the stall current is way past that, and therefore way past the Jrk’s peak limit of about 30A. If your current is really about 5-10A, it might be doable, but the point of the Jrk is to do position control, in which case you are frequently near the stall point of the motor, so your current might be more than you expect. (If you do not need the closed-loop features of the Jrk, you might consider our
simple high-power motor controller.)

- Jan

Hello Jan and thx for rapid answer!

My winch can pull a maximum weight of 900kg.

So it have different draws amps in different cases:

  1. winch pull 100kg = 5amps
  2. winch pull 300kg = 8amps
  3. winch pull 600kg = 16amps
  4. winch pull 900kg = 25amps

So, 25amp is the maximum limit of drawing.
The motor (how i will use it) will be costantly at 5-10 amps. Just in some rare case will be 13-15amps.

Sure, if I use the motor costantly at 25amps so I understand I am pretty near the maximum amps that jrk can handle!

But if I understand you, in this case (costantly 5-15amps max) it’s all Ok right?
The Jrk can handle peaks of 30amps so I am very under the bad limits! right?

And in the last, If I pass the 30amps peak limit of Jrk, so I can cause damage to it?

Thank you!


No. Your understanding is not correct. If it can move a load at 25amps, the stall current of the winch could be twice that (50 amps). When a DC motor starts to move it draws the stall current for a brief moment. If the motor changes it direction quickly, it can draw up to twice the stall current (maybe 100 A with your motor). If you use 25 A continuously you are way above what the jrk 12v12 can do. It can only supply 12 A continuously. The 30 A peak is only good for a short time (less than a second). If your motor ever draws above 30 A (even for a very short time), the motor driver chip might break. If you are ever drawing more than 12 A continuously, you cannot expect the jrk 12v12 to keep up for too long.

- Ryan