Motor Not Starting with Encoder – Works Fine in Sensorless Mode

[FZTHUB]

Good day,

First, a bit about my hardware:
Motor:

• 4 pole pairs

• 24V

• Max speed: 3080 rpm

Inverter board:

• B-G431B-ESC1

• External power supply via power adapter

Encoder:

• 490-AMT10E2-V set to 640 PPR

Now to my problem:

When I start the motor in sensorless mode, everything works as expected.
However, as soon as I use the encoder, it stops working — the motor just twitches briefly. In Motor Pilot, it briefly switches to "alignment" but immediately falls back to "idle."

In the plot, I’m monitoring the ENCODER_EL_ANGLE, which moves smoothly between -180 and +180 degrees without any noticeable jumps if i turn it by hand.

I also tried setting the encoder as an auxiliary sensor just to observe it while the motor is running, but even then, the motor doesn't work — same behavior as described above.

I’ve read the encoder data using my own code, and it works even at higher speeds.

Changing the encoder direction or adjusting the alignment current and time didn’t help either.

Does anyone have any idea what could be wrong?

Thanks in advance!

[GMA]

Hello @FZTHUB,

Using Main Speed Sensor in sensor less mode, and auxiliary Speed Sensor in encoder mode, motor does not spin?
If motor is able to spin, are the two electrical angle signals in phase?

[FZTHUB]

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@GMA wrote:

Hello @FZTHUB,

Using Main Speed Sensor in sensor less mode, and auxiliary Speed Sensor in encoder mode, motor does not spin?
If motor is able to spin, are the two electrical angle signals in phase?

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Hello, thanks for your answer. Yes, that's correct – when I select the main speed sensor as sensorless and do not configure any auxiliary sensor, the motor runs.
However, as soon as I set the auxiliary sensor to encoder mode, the motor no longer starts.

So unfortunately, I’m not able to test whether the two electrical angle signals are in phase or not.

[GMA]

Hello @FZTHUB,

Does MC Motor pilot reports an error? 

[FZTHUB]

"When the encoder is connected as an auxiliary, there is no error. When I press start, it goes into align mode for about 0.5 seconds and then returns to idle. No error is shown, even then.