Power expander issue

  1. We plug in a fresh battery into our power expander.
  2. We plug in our drivetrain motors into our power expander.
  3. After about 20 seconds of driving, our power expander light goes red.

We have a fully charged battery, and I confirmed that by plugging in the battery to the microcontroller. What is happening here?

Power expander red led means the battery is low.

https://vexforum.com/wiki/index.php/Power_Expander

Are you using the status port? Does it go orange before it goes red ?

When it’s red, does it blink slowly? If so, you are tripping the power expander’s circuit breaker. You said your drivetrain motors are all plugged into your power expander. We learned earlier this season that drivetrain motors experience more strain and tend to draw more electrical current than lift and intake motors. Because of this, having all of your drivetrain motors on the power expander is likely to trip the expander’s circuit breaker. Try plugging 2 of the drivetrain motors into the microcontroller instead, and swapping 2 other motors onto the power expander.

If the light does not flash when it turns red, then it means your power expander is not receiving much power from the battery. You stated that the battery is fresh and can power the microcontroller. In this case, there is a something wrong with your power expander.