Pole Pair Mismatch error

I am trying to setup my CubeMars AK10-9 with an ODrive Pro. My current setup has the Pro mounted on top of the motor, with the encoder lined up with the magnet prebuilt into the motor. When calibrating through the GUI, I get a POLE_PAIR_CPR_MISMATCH error. The strange part is that the message changes the expected value each time I try to reboot and and retry. Also, sometimes, the driver calibrates “correctly”, but when I try to control it, the motor makes noise which leads me to believe there is still some error.

I have browsed the forums and it seems many people have gotten this issue due to an encoder alignment issue and others with some wiring problems. Two potential sources I can see being the issue are the distance to from the magnet to encoder (about 4mm vs the recommended 1-1.5mm) or potential bad soldering between the built-in motor leads and wires I had to solder on to extend them to reach the screw terminals. As far as I can tell, the encoder is aligned with the magnet, just relatively far away.

Ah yes - that 4mm is definitely the issue. The field strength drops off really fast (inverse square law!), and can get distorted easily by ambient soft iron – especially because the built-in magnets are typically pretty thin/weak.

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Thought so! Reducing the distance eliminated all the issues! Thank you so much!

Great to hear!! Best of luck :slight_smile: