HELP!!! Electrical Problem!

During competitions while we are running all nine of our motors, the circuit breakers seem to be breaking, which stop the motors from working, therefore we cannot move our robot or do anything.

We have a power expander with a second battery. We have four 2 wire 269 on the power expander. And two 2 wire 269 motors, along with three 2 wire 393 motors in the microcontoller.

We have already rewired it to distribute the 393 motors, and have changed out the microcontoller.

But the circuit breakers keep tripping, does anyone have any ideas or ways to help. Thank you.

What kind of load are your motors under? How heavy is your robot/arm? How many motors and what kind of gear ratio do you have?

Pictures would be nice. :wink:


We are running 2:1 on the wheels. And the lifts are lifting a pretty light load.

What size wheels, and how many of what kind of motors are powering them?

A power expander has a 4 Amp limit for all 4 ports combined.
Cortex has one 4Amp limit for combined ports 1-5.
Cortex has one 4Amp limit for combined ports 6-10.
If you experiment with spreading your simultaneous heavy loads around these 3 groups, you may find one that works better that what you have now.

Consider changing your game strategy to avoid running all 9 motors at once.
If you have a rotary encoder, try running it on the motor axle (unconnected from wheels, or at least with wheels off the ground) to get the minimally loaded axle speed. Then get the max speed while spinning the robot in place. If the spinning speed is less than 1/2 the unloaded speed, it would be advantageous to change your gearing for more torque.
The highest gear ratio is not the fastest robot, said the guy with 5:1 speed ratio on a non-moving robot.