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Encoder position resetting to 0°

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Michelle90
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Last seen: 6 months 6 days ago
Joined: 2022-08-14 14:45
Posts: 2
Encoder position resetting to 0°

Hi again!
My effort of running an AC servo (MiGe 130ST + FLIPSKY Mini FSESC6.7)  in foc mode ran into this weird (to me) issue.  I was able to spin it (sorta) in sensorless mode but ABI encoder mode does not work since the encoder reports 0° everytime servo spins up (sensorless mode since in encoder mode it stalls obviously). In encoder mode it can turn from 348°to 0° back and forward normally.  Another fact is that no matter the angle it always reset to 0, BUT when turning by hand and do have full 360° feedback. I did measure signals with an oscilloscope and logic analyzer, both showed that all three signals are present and in good condition all the time.
Has anyone seen such an issue before? Hardware issue or EMI interference somewhere? Thinking about RC filters that had to be removed when using encoder instead of hall, that still apply to VESC6? Schematic shows no RC filter in the V6, just pull-ups but did not check the actual board itself before installing it.

Here are some pics that may tell something?

Turning by hand

Motor Run

Value resets 

 

Any input is much appreciated!

GijsB
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Last seen: 8 months 1 week ago
VESC Free
Joined: 2021-10-14 17:05
Posts: 3

Hi Michelle,

 
I'm a bit unfamiliar with VESCs myself, but I did have an issue similar to yours. In my case, I simply forgot to use the encoder alignment/calibration tool. You can find it at the bottom of the Motor settings -> FOC -> Encoder tab. Also, make sure that the resolution and direction of the encoder is set correctly. Hope this helps!

Best regards,

Gijs