TMC5160 Overheating and missing steps

I'm using klipper with an SKR 1.4 board to control a pen plotter with an airbursh mounted to a wall. The thing is big and uses 3A nema 23 steppers. The drivers I'm using are TMC5160 delivering 3 amps both as run and hold current. The motors run really really hot and the machine misses steps, normally after a while of being operational. My guess is that there might be some thermal throttling. Also, I don't get the rsense value, is that dependent on the motors that I'm using? What is the best way of tackling this issue? Should I reduce the running current? Wouldn't that make the motors weaker? Also, about spreadcycle and stealthchop, what do you think is the best way to assure that the motors have always as much power as possible? Any guidance with these topics would be great, thanks a lot!

First of all l, don't set the current to the max but slightly below. Also, fo you have cooling elements and active cooling with a fan on the drivers?

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http://www.marinusdebeer.nl/

Nema 23 steppers are not that big, and properly designed , mounted and heatsinked TMC5160 drivers with their external mosfets can easily handle more than 3A. But not stepstick-format drivers. Get yourself a better controller that is designed for high current motors. Duet 3 will drive Nema 34 motors at up to 4.5A RMS, 6.3A peak.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

I double checked my datasheet and it turns out that I was convinced that my motors could handle way more current, I don't know why. So I've been feeding them way more power than I should. I will swap them for bigger motors!

Quote
dc42
Nema 23 steppers are not that big, and properly designed , mounted and heatsinked TMC5160 drivers with their external mosfets can easily handle more than 3A. But not stepstick-format drivers. Get yourself a better controller that is designed for high current motors. Duet 3 will drive Nema 34 motors at up to 4.5A RMS, 6.3A peak.

Thanks a lot for the recommendation! Do you know of any drivers based on the TMC5160 that are not in the step-stick format?

Do you actually need bigger motors? Might turning the current down be a solution?

I don't know of any separate TMC5160 driver modules not in stepstick format other than the Trinamic evaluation board. Perhaps someone makes one in Bigfoot format.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].