Terx Jr stoped the motors by blocking them

Hello all

I have an Arduino-Board which sends the commands to the Trex Jr. The Trex controls one Motor without encoder.
The problem is now that, when I block the Motor the Trex Jr stop to send PWM-signals to the motors. This is happen with a current of 1 A to 2 A and the current limit is about 5 A (current limit parameter = 60) appointed.
I use the Trex Jr in the joint mode.
I also tried this experiment without a current limit and the same thing happens…
I could exclude that its cause of the Arduino, it happens even when I send a constant signal.
I tested different things:

  1. I blocked the Motor and gave only few power. The Motor stopped with less than 1 A current.
  2. I blocked the Motor and gave full power. The Motor stopped with more than 2 A current.
  3. I increased the friction. So the Motor could turn but had a big torque. The Motor Stopped with a current between 1A and 2 A.

Thanks for the support


I don’t have a very good understanding of your problem, so I have a few questions:

  1. How are you powering the TReX?
  2. Do you know the stall current of your motor at the voltage you are using? If it is a motor we sell, can you link to it or give me the exact item name or part number?
  3. How are you measuring the current draw values you are listing?
  4. When you say that the TReX Jr stops sending PWM signals, is it encountering an error (e.g. have you checked the status byte?) or is the TReX Jr resetting (e.g. do you see the LEDs blink like they do when you first power it up?)?

Current sensing is not available in joint-motor mode, so it does not make sense for you to have current-limiting enabled.

- Ben