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I'm using:

  • Workbee CNC
  • SKR1.4 Turbo with TMC5160
  • Marlin 2.0

Steppers suddenly disabled during job. But, they get back working as soon as you restart the machine.

I've had the problem twice with this setup. Once with the Z-axis and once with the Y-axis (that uses two steppers, one keeps on working while the other was disabled).

When I had the problem in Z-axis, I decided to lower current on that axis from 2 A to 1.9 A. It's already 1.5 A for both steppers on the Y-axis.

Just switching off and on the machine is enough to let steppers work again say it seems not to be a wiring problem.

Any clue? Any advice is welcome.

Greenonline
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Bernard de Terwangne
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  • What steppers do you use? NEMA 17 or 23? A current of 1.9-2 A means you need to actively cool the stepper drivers! – 0scar Nov 26 '22 at 23:12
  • did you check the G-code? Does the board feel overly hot? – Trish Nov 27 '22 at 12:24
  • Hi, I'm using Nema 23. The one configured with 2A are bigger ones. Steppers are warm but not hot. I can hold them in my hand indefenitly so I assume it's not too much current for them. G-code is as generated by fusion 360. It includes long movements on the Y axis as I'm making a guitar neck. Its quite intensive on the CNC. Much wood to be removed. Heat sinks tend to be quite hot. I can keep a finger on the top for around 3 s. This says noting on ship temperature that might well have exceded a limit. My guess is overheating of drivers. I'll add a big fan and I hope this will fix it. – Bernard de Terwangne Nov 28 '22 at 07:19
  • Check if your stepper drivers are overheating. Driving a nema23 motor is no joke, and at a 2A current, the drivers could be getting a little toasty, tripping the temperature limit and disabling the drivers. – CryptoAlgorithm Nov 29 '22 at 06:42
  • Quick update : I've added a 120mm fan on top to the BTT card. Everything sems cold now. First I thought it was OK but I had it twice again with Z axis. I had it 5 times now. Only comes on long jobs (after at least 1 hour of precessing). Any clue is welcome... Bernard – Bernard de Terwangne Dec 07 '22 at 15:38

1 Answers1

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I think I fixed the problem.

Marlin was configured in hybrid mode with stealth chop mode at low speed then spread cycle when the stepper goes faster.

I removed stealth chop and set spread cycle at any speed and it seems to be OK.

I could let the machine work for hours with no issue

Bernard de Terwangne
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