Pololu Robotics & Electronics
Menu
My account Comments or questions? About Pololu Contact Ordering information Distributors

Pololu Forum

TReX Jr. keeps reseting itself


#1

I am trying to power a motor with the TReX Jr. using a standard 9V battery as the power source. The battery is attached to the proper screw terminals on the TReX via a connector.

I tried connecting the battery directly to the electric motors (without a motor controller) and it worked fine. I have a chassis on which the motors are connected to a wheel base. However, when the motors are attached to the TReX and I try to power the motors at full speed (or thereabouts) with the TReX the wheels don’t have enough torque to turn and the motor stalls. When the motor stalls it causes (what seems like) the TReX to reset itself because the red status light blinks a few times and temporarily cuts off power to the motors. Also, it might help saying that the TRex is connected to the arduino via TTL.

I am thinking that the TReX might need more than 9V for a motor to turn at the same rate as it would if the battery was connected directly to the motor because of the logic voltage that it takes to operate the motor controller. However, I am pretty new with this and I’m not exactly sure what or why this is happening. Any input would be much appreciated.

Thanks


#2

Hello.

A 9V battery is a very bad choice for high-current applications like driving motors because they are not capable of supplying large amounts of current (the voltage drops significantly). I expect your problems will go away if you use a more appropriate power supply (e.g. AA batteries or battery packs).

By the way, this is one of the points covered by our troubleshooting advice post that is at the top of every forum.

- Ben