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makerbase-mks / MKS-Robin-Nano-V1.X

MKS Robin Nano is a powerful 32-bit 3D printer control board with STM32F103VET6. Support Marlin2.0. Support MKS Robin TFT24/28/32/35/43 touch Screens. The motherboard integrates 5 AXIS interface, hot bed, 2 heating heads, 3 NTC100K, 1 MAX31855.The motherboard integrates After shutdown. Support MKS Robin WIFI for cloud printing and supports firmware update by SD card…
https://www.aliexpress.com/item/33013776323.html?spm=2114.12010612.8148356.5.320565f4m9CS1x
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Excessive heating of the motors #22

Open LuigyU opened 4 years ago

LuigyU commented 4 years ago

After waiting a long time due to the delay with the shipping of the covid-19, I finally received the item. Then I installed it on my printer, following all the instructions I received from its github portal and with great satisfaction to see that everything was working correctly.

But my disappointment was that during the first impression I noticed that the nema17 0.9A motor of the Y axis was overheated (to such an extent that it could not be touched by hand because it burned, it was almost like the bed at more than 70º or more ) The X and E0 axis motors were also warming up but were acceptable.

Firstly, see if my Y axis car had any impediment in its movement that made it go wrong and it was not.

I understood that the voltage with which the various MKS TCM2208 V2 came as they come from the factory is too high (1,171) and I proceeded to lower it as I had previously on my old board. (0.80V)

Still, it was still very hot, and I proceeded to lower it even further, to the 0.7 limit of the driver. The temperature of the Y motor was hot and seemed correct but in this situation, I was already missing my motor steps.

Believing that the driver could be damaged, I changed it with another, but it was still just as hot.

Perhaps suspecting that my motor might be damaged, I would change it for a different and stronger one, a 1.2A nema 17 and adjust the driver to 1V to test it. I had to stop printing (which was an hour) because the engine was excessively hot.

All my mounting information that I have followed step by step and the software I have found here. https://github.com/makerbase-mks/MKS-Robin-Nano/tree/master/Nano%20firmware%20v2.x.x and from the videos https://www.youtube.com/watch?v=_qMahRSUtDY Is what I have done correct?

The X, Z, and E0 axes are fine, but I only have the problem on the Y axis.

I don't know what to do anymore, I have everything stopped and I can't print anything without compromising the integrity of the printer. I really need your help and advice

chshkhr commented 4 years ago

Hi, correct Vreffor TMC2208 is 1,69V. While correct Vref for TMC2209 is 2,82V. Vref is proportional to Irms (as for TMC2008 Vref = (Irms * 2.5V) / 1.77A = Irms * 1.41 = Imax). So the more Vref you set the less current you need to get the same power P = I * V. So to reduce consumed current (which is the reason for motors heating) you need to increaseVref. Am I right?

thierryzoller commented 4 years ago

Sounds counterintuitive to me, I am interested in the responses.

chshkhr commented 4 years ago

As I understand now we should look at not only on RMC of stepper driver but on RMC of stepper motor because it's much lower... "For NEMA 17 motors from 3D printers the current is in general in the range of 0.5A to 0.8A RMS, which is a reference voltage (Vref) of 0.7V to 1.1V." Here is the source

Vref is not the working voltage but only reference value to setup maximum current from TMC driver... So I was wrong... My Robin Nano with TMC2209 and Nema 17: