My motor seems damaged? Will the motor be damaged by running it at full throttle without a propeller attached? What is the RMA process?

[matthiaswilkens]

My second flight attempt today resulted in failure when once again the drone inverted at takeoff - as with last time, leading from the rear CW motor - which I'm convinced must somehow be "slow". I have done and re-done the ESC calibration, and I've used the MAVLink Console to try to compare motor speeds etc. but they all "look" fine until you actually attempt takeoff. Is there anything else I can try, or is this most likely another motor defect? I have spares, since the replacement for my prior failure was only available as a 4-pack - but I wasn't sure if there was anything else I could try first, since the motor swap is a pretty time-consuming process... I don't think it's an orientation/compensation thing since it always goes to that corner regardless; is there anything I can do to confirm that the IMU is performing correctly - or any IMU callibration I can try? Thanks!!

[matthiaswilkens · Accepted solution]

What I meant by testing to see if the motor can reach max rpm is to investigate if the specific motor would stall beyond a certain throttle range. a) If the motor stalls/run at low rpm at the start itself, either ESC or motor issue. Swap each to find the faulty. b) If motor stalls above 50% throttle, it might be a battery/ESC/loose contact issue. Check your battery voltage/power distribution section/wiring to see if all the leads are soldered properly. It can happen due to loose contact. Else, the power draw might be high which the battery is not able to deliver or the ESC is cutting the supply down as it goes above its allowable range. Try with a fully charged lipo / more capacity battery / more capacity ESC. Also, see if the throttle range is set correctly in TX. c) If all these are fine and the issue is during flight, try with a different prop with the same dia, less pitch or smaller dia, same pitch. PS: Never run the motor at 100% throttle. From my experience, most motors will reach saturation speed below 60-70% throttle most of the time, effectively reaching max rpm way below 100% throttle input. The motors, if consistently run at high rpm without load would overheat it quickly. So better to do this check within a couple of seconds and bring the rpm down without letting it overheat. Also, all motor/ESC tests are done without props as far as I know. So I am not sure if it is an issue If I miss any point here, please fill me up. Regarding drone balance, I am not sure of another method, Maybe you can check on prop balancing too. 

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