New Stepper Motor shorted on Duet3D mini5+
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I am running a Duet3D mini5+ with Klipper firmware on a modified Prusa, my old extruder stepper suddenly shorted when I tried to load filament. It was not unexpected since it has worked in hot environments. I connected two other stepper motors, a similar x-axis stepper and a bigger one with different specs and they ran perfectly fine and cool using the same driver.
So I went out to replace the stepper with a better pancake model since I build a pulley system for my printer. I connected the new stepper to the x-axis driver to see if was working properly ( so I don't need to heat up the hotend) and it was working well in SpreadCycle as well as stealthchop mode. So I restarted my machine and connected the stepper to the Extrusion-driver. To test the movement I wanted to perform an unload_filament procedure, so the nozzle was heated to about 180 degrees and than I gave the unload_filament command. And then the stepper motor showed exactly the same issue that my old stepper motor had, rattling in it's place. It was extremely hot, so I disconnected the stepper right away. The resistance of one phase of the stepper was dropped to 2.40Ohm, so there was a short. Is this simply bad luck, faulty stepper motors do exist, or is
it possible that the board is somehow giving the stepper motor max current when heating up the nozzle?The configuration file has been checked by other Klipper users, and does not seem to have any errors
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Have to say. Have you tested it with reprapfirmware 3.4 installed?
With RRF installed I'd ask you to send M122 and copy paste the diagnostic reports and see if any error messages are generated when you try and use the driver.
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Maybe that's related to klipper firmware initializing drivers in a way that's not working well with Duet3Ds board design? Ref https://klipper.discourse.group/t/tmc-drivers-will-be-full-power-when-vin-is-restored/1058
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Thanks for the replies, unfortunately I saw the last one too late.
It seems to be exactly this issue, since I just had another motor short out. At least now I know what caused it, because it was driving me insane. The replacement motor printed for a couple of days without any issue though so at first I thought I had a rare faulty stepper. But it seems it most definitely has to do with this bug. Both three steppers burned out exactly as written in the description, feel really bad that 3 stepper motors got burned out this way before finding out the cause.There should be a warning about this very thing in the Klipper Duet example files. Or at least somewhere that a Duet user will see.
The best solution/hack to solve this issue with Klipper is to disable the 5V line it seems.
