Hi, I was about to upgrade my board from a 4.2.7 to an skr mini v3. On my printer I upgraded my Y stepper motor to a 42-40 and had to adjust the VREF on the 4.2.7 board to give more power to properly use the motor. On the 4.2.7 board all I had to do was turn the screws to change the VREF. There are no screws on the skr mini v3. Does anybody know how to change the VREF for this board?
Ive read you can set it in the firmware, but I use this site to build my firmware so Im unsure how to add that in.
You can set the stepper current using the M906 command.
Is this the same as setting the vref? like if I make the current .97mA, is that the same as setting the vref to 1.20 V?
As per the documentation, you set a specific current in mA - ie M906 E600 will set the extruder current to 600mA.
and to confirm, the range for a 42-40 is 870mA to 1000mA correct?
You would need to check the specifications of the stepper you got. They can vary.
Just keep in mind that the spec sheets probably refer to a peak current - whereas the stepper driver setting will be in RMS.
To get RMS from the peak value, multiply the peak value by 0.7071.