New Motor Issue

This could easily be user error but I’m running into the following problem:

When I first turn on and activate the motors they run fine for about a minute, after that they get progressively weaker to the point that you can hear the motors are turning, but have virtually no power. Tried it when the battery is plugged in, same problem. But it’s not consistent, one day it will work every time and the next this will happen. Any thoughts?

Is the motor warm? How much power is it drawing?

Not warm, didn’t check how much heat it’s drawing

Any other suggestions?

Is it a 393 or V5 motor? Are you running it with a load attached or is it running without anything attached to it?

V5 with a load

There’s likely too much load on it. Unlike with 393s, V5 senses when it is being overworked and slows itself down. We encountered the same issue when we used our flywheel (set for V5 with 100 rpm) with our 200rpm motors just to test it

Note that the motor API offers has telemetry, including temperature, torque and power. Both in VCS and PROS. vex::motor::temperature(units), motor_get_temperature(port), pros::motor::get_temperature().

You can try graphing (or printing) your motor temperature with time.

I also just remembered: You can get a lot of stats on the brain’s screen. If you go to the info for that motor, it should tell you what the command rpm is and the real rpm. If the command is at 200 rpm (for a motor with a green gear casing) then the motor is being overworked. If the command is less than 200 rpm, then programming would be the issue

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V5 motors is what is being referred to. Your experience is with 393 - which is not directly applicable to the new system.

I am not sure what V5’s thermal characteristics are.