If a motor spins less than half as fast as usual, is that a sign it’s burnt out?

I don’t know anything about mechanics, I’m a coder. If a motor is spinning half as fast as it would yesterday, and it can’t even spin when I set it to 35% power, does that mean it’s burnt out? Or would it have stopped working entirely? I ran it past what it’s supposed to handle when testing it yesterday on accident, that could be something.


What type of motor is it, and what do you mean by past what it’s supposed to handle? With a little bit of information, someone could probably diagnose the problem.

If by “ran it past what it’s supposed to handle” means motor.set(value greater than 1), that is not the cause. You can’t fry a motor only by setting it in code, it can however be a mechanical failure caused by use of the code. Wiring issues are also possible. We would need to know far more about the condition, but it sounds like you may have some friction in the motor. If it is a brushless motor, check where your screws are in the motor; some of them may have mounting screws contacting the innards that not only damages the motor but also causes the frame to be grounded.

It is a sim, thickness of a water bottle and about 5 inches long

At 72% power it normally spins at 26,000 encoder units but now it only spins between 14,000 and 16,000 and fluctuates more than usual. We are running simple PercentOutput in code, no feedforward or anything complicated.

sounds an afwul lot like a burn out. it sounds like this is on your shooter, what pulley ratio are you running to the flywheel and did you add weight to your flywheel?

I’m going to disagree on the burn out as an initial path of investigation. CIMs are notoriously tough to kill, particularly that quickly. They can and do wear out, and they can fry, but it’s not common for that kind of speed.

Any idea how old the motors is?
Do you have a second motor that you can swap in to check performance?
Did the motor (and its driven system) sound different today than yesterday? (Or compare to the fresh motor.)

I would also double-check the encoder wiring–it sounds like there’s some extra noise in there, so it’s worth seeing if anything went loose.

We will be back in the pits to check it out today, and I will keep you posted. We do not have another motor of the same type, and it was making strange sounds during tuning and stuff when we ran it too high but sounded fine yesterday.

Someone else asked - what do you mean “ran it too high”? You cannot physically damage these motors by giving them maximum voltage - even plugging them straight into the battery won’t damage them. Unless you stalled it, or ran it until it was so hot you couldn’t touch it.

There are motors in the spare parts case, don’t hessitate to get one from it, that is why it is there.

This topic was automatically closed 365 days after the last reply. New replies are no longer allowed.