Hey there! We experienced some problems with the motors of our robot while participating in the national VEX competition. We are using a holonomic drive and a six bars lift. During the testings we didn’t experience any problems but while playing matches the motors of the six bars and the holonomic drive stopped working then worked again for some seconds then it would stop again after that. We are using 4 motors for the six bars, 2 of each side are linked with a Y cable and 4 motors for the holonomic drive. Any idea how to fix this issue? Thanks in advance
whats your wiring configuration, it may be putting too much load on the ptcs and tripping them
This is no doubt PTC tripping. These are protective self resetting fuses intended to stop the magic smoke from escaping your VEX EDR controller and 393 motors.
If during the match you were pushing game objects around perhaps the driver over-cooked it by continuing to drive hard against objects/walls/fences which resulted in stalling out the drive motors. This alone could cause the VEX EDR controller PTCs to trip resulting in the loss of your lift motors as well.
That sounds like a PTC tripping, and a simple fix we did was to add a power expander and re-wire the ports.
The cortex has 2 breakers, one on ports 1-5 and the other on ports 6-10. We found it best to split our chassis and lift among the two breakers, and the same with our power expander, putting two from the lift and two from the chassis into it. This basically adds another battery to your robot.
Also, you might wanna stay away from ports 1 or 10, since they are known for failing.