Motor_error_unbalanced_phases

Hi,

Im trying to set up odrive system. We have v3.6 oDrive board at 24V and ODrive Robotics D6374 - 150kv motor. All is powered by lab supply 24v with 5A current limit.

I followed commands in getting started section of docs. I did not connect encoders yet but jumped right to motor calibration just for test to see if motor will spin. But after calibration command:

odrv0.axis0.requested_state = AXIS_STATE_MOTOR_CALIBRATION

Motor is not moving anyhow. It beeps and than dump_error(odrv0) shows this error code in motor section:

MOTOR_ERROR_UNBALANCED_PHASES

What can I measure and what are the steps i can perform to find the cause for this ERR.
Thx for any advice.

Hmm, I’m surprised it’s even beeping. UNBALANCED_PHASES happens when there is an issue with the motor wiring. Please check that the motor wires are OK, that they all show continuity, but aren’t shorted together, etc.

I’m having the same issue after upgrading to firmware version 0.5.2 using the same D6374 motor. After running odrv0.axis0.requested_state = AXIS_STATE_FULL_CALIBRATION_SEQUENCE it will stop calibration immediately with MOTOR_ERROR_UNBALANCED_PHASES and sometimes also MOTOR_ERROR_CURRENT_LIMIT_VIOLATION. Mine does not beep however.

Everything used to work fine on 0.5.1. Other than a firmware upgrade, nothing changed in the setup.

I have having the same issue after upgrade the firmware. Are you able to fix the problem?

I don’t remember what the initial firmware version was prior to the update, but after updating, the firmware is version now 5.4. It was working fine with my janky setup before the firmware update, then after it it stopped, no calibration sequence, no beep, no turn, throwing an unbalanced phase error. After trying everything else I fixed this problem by swapping the wire for a thicker gauge. For this I had to start from scratch and rule out everything else. I reset the drive configuration to factory states and re-entered my important configurations (no effect).

My initial setup was meant to be temporary, but I was using crappy alligator clips and high gauge wire. 2 phases were 16 AWG, and one was 20 AWG. When I measured the phase resistances with a multimeter, 1 of my phase resistances had significantly lower resistance than the other 2. This led me to believe that the phases (in my case C-A) which had the thicker wire was the culprit, while the other two phases pass through one thicker and one thinner wire, therefore increasing its resistance. I switched to 12 AWG and it worked again.

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