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M201 Stepper Motors very weak 4988 Stepper Driver Vref
Posted: Mon Jul 08, 2019 1:48 pm
by realfox81
Hello, i recently assembled a m201 kit and i was very disappointed because of the weak motor power. I easily can stop the rotating shaft of the nema 17 motor. I adjusted the vref of 4988 to 1,05V this is the highest point i can go, after rotating further i go back to 0,2v. What can i do that the axis have more power. I can rewind the filament out of the extruder without pressing the lever, motor makes some noise but seems to be running freely.
I have more than 10 3d printers and this is a phenomen i never occoured. The voltage on the psu is 24v like it should be.
Can someone tell me the vrefs for each 4988 driver so i can adjust them correctly to the necessary voltage?
Thanks
Stefan
Re: M201 Stepper Motors very weak 4988 Stepper Driver Vref
Posted: Mon Jul 08, 2019 2:17 pm
by William
Hi, you can refer to this；
- 步进驱动版.png (132.58 KiB) Viewed 10435 times
The clockwise adjustment is large, and the counterclockwise adjustment voltage becomes smaller.
Re: M201 Stepper Motors very weak 4988 Stepper Driver Vref
Posted: Mon Jul 08, 2019 2:29 pm
by realfox81
Hi, thanks for your reply.
The standard (factory) setting was 0,5v -> i turned to 1,0v, but is also really weak. The extruder motors move barely (yes the hotend is preheated).
I cannot move to 1,2v -> over 1,05v the poti goes back to 0,03v
Re: M201 Stepper Motors very weak 4988 Stepper Driver Vref
Posted: Mon Jul 08, 2019 2:37 pm
by William
Hi, Is it your extruder motor is working properly, you can try to swap the motor wires of the other axes with the motor wires of the extruder to see if there is a problem with the motor.
Re: M201 Stepper Motors very weak 4988 Stepper Driver Vref
Posted: Mon Jul 08, 2019 3:07 pm
by realfox81
I swapped the wires, on other motors its also weak. X, Y, Z Axis and the Extruder motors are very weak. I will make a video to show it whats going on.
Re: M201 Stepper Motors very weak 4988 Stepper Driver Vref
Posted: Mon Jul 08, 2019 3:23 pm
by realfox81
This shows how weak the z motors are (for example) the other motors are not stronger! They have no holding power at all. On my tronxy x5s i need more force to turn the z motors after i have operated them by lcd.
https://www.youtube.com/watch?v=i328fNDKqXM
Re: M201 Stepper Motors very weak 4988 Stepper Driver Vref
Posted: Mon Jul 08, 2019 3:36 pm
by William
Hi, From the video, the motor can run normally. If you feel that the voltage is insufficient, you can try to replace the engine board to try.
Re: M201 Stepper Motors very weak 4988 Stepper Driver Vref
Posted: Mon Jul 08, 2019 3:59 pm
by realfox81
The Extruder Motors are so weak they are not able to push enough filament through the nozzle. Its under extruded. When i push the filemant by hand with a bit more force, the filament will extrude properly, so the nozzle is not clogged.
Re: M201 Stepper Motors very weak 4988 Stepper Driver Vref
Posted: Mon Jul 08, 2019 4:04 pm
by William
Hi, you can refer to this:
- 耗材推进原理.png (143.97 KiB) Viewed 10421 times
Re: M201 Stepper Motors very weak 4988 Stepper Driver Vref
Posted: Mon Jul 08, 2019 10:48 pm
by _kaktus_
realfox81 wrote: ↑Mon Jul 08, 2019 1:48 pm
Hello, i recently assembled a m201 kit and i was very disappointed because of the weak motor power. I easily can stop the rotating shaft of the nema 17 motor. I adjusted the vref of 4988 to 1,05V this is the highest point i can go, after rotating further i go back to 0,2v. What can i do that the axis have more power. I can rewind the filament out of the extruder without pressing the lever, motor makes some noise but seems to be running freely.
I have more than 10 3d printers and this is a phenomen i never occoured. The voltage on the psu is 24v like it should be.
Can someone tell me the vrefs for each 4988 driver so i can adjust them correctly to the necessary voltage?
Thanks
Stefan
Stefan ...
If you would like to take a moment to read the modest content of this part of the forum, you will get an answer to the question.
If you think your printer engines don't have any power, I would first check the connections.
Then I would find the parameters of the motors and the nominal current value.
And then he calculated the Vref voltage for each of the motors.
You say you have so maaaaany printers. So I think you should have experience in this area
Is that so? I don't know...