First of all, thank you for taking the time to read this.
I have some questions on polarity of tiny brushed coreless motors. I recently purchased these:
to build a light micro quad. Although the seller mentioned that 2 motors are clockwise and the other 2 are anti- clockwise, I wondered if it makes any difference. I did try running the anti-clockwise motors reversely, they did spun clockwise without any noticeable issue. The voltage drop across these motors that were ran reversely were the same as the ones run according to the specified polarity. However, perhaps due to coincidence, I noticed that after a while, these motors that were not run according to its specified polarity seemed to not work (not spinning anymore when the same voltage was provided).
I read about this online, and I got conflicting answers. Some forums mentioned that polarity does not matter, some said that the performance and the life span of the motor would be affected if it is made to run on reverse. If I am not wrong, I understood that for this kind of DC toy motors: Amazon.com: Topoox 12 Pack DC Motor 1.5-3V 15000RPM Mini Electric Hobby Motor for DIY Toys Science Projects: Toys & Games , the polarity depends on how you wire it, there isn’t any fixed polarity. Would you please provide some basic technical insight on this?
In case you need to know, my motors are connected to a motor driver DC Motor + Stepper FeatherWing Add-on For All Feather Boards : ID 2927 : $19.95 : Adafruit Industries, Unique & fun DIY electronics and kits. I powered the driver with a Lipo (3.7 V, 2000mAh). The voltage drop across the motors were low- about 0.7 to 0.8 V per motor, and the input to the driver measures 3.0V. The lipo was measure to be 3.9 V when not connected to the driver. At this stage, I was only testing the motors.
So in summary, I have a couple questions/ issues here:
- I noticed 1 or sometimes 2 motors would stop spinning after a few times of power up, I wonder if this has to do with me wiring the motors to run in reverse directions. The motors that did not spin had about 2 times the voltage drop of the ones that are spinning during powered up.
- The voltage drop across the motors seems low, the coreless motors requires about 3.0 to 3.7 V to operate according to spec.
- When given the same speed, all motors would spin, however one side of the frame ( the sides with motors connected to M1 and M2) would lift up, but the side with motors connected to M3, M4 would not. The propellers and motors directions are matched accordingly, so I would think this is issue is related to the motors.
- I am unsure if the polarity of the motors brushed coreless motor matters. I would like to know if I can just wire these motors in reserve and have them run in the opposite directions? I know they will spin, but I wonder if they would run slower ( I have no way to measure their speed but the voltage drop seems to be no different) or they will burn out sooner.
Thank you for your time and help once again.