Geeetech

driver voltage

hello friends I would like to know what are the voltages of the a20m drivers with board Gt2560 V3.0 the drivers are allegro A4988 with resistance R200 since and to turn them in ​​days past and were unconfigured reading on the internet I found a formula

Vref = Imax (8 x Rf)
Vref = 1Amp (8x0.2)
Vref = 1amp (1.6) x 70%
Vref = 1.12

this formula is well applied to all drivers or I could pass the correct voltages of each driver please help

Axis X:
Axis Y:
Axis Z:
Extruder 0:
Extruder 1:

I moved them and I did not take the precaution of taking these voltages before making the movement

I thank you because I have my a20m unarmed because I could not with the voltages

Hello.


You must read the value of the RF resistor from the elements used. These modules are mounted in very different versions. I have seen with 0.1 and 0.2 ohm resistors. There are also versions without them.

My doubts aroused only one record.

chacal wrote: Mon Mar 18, 2019 9:23 pm ...
Vref = 1amp (1.6) x 70%
...

I agree with the rest.

Hi friend
reading the resistance is R200 this means it is 0.2 and 70% is for full sptep but should remove the jumpers in this case we handle 1/16 step or the voltage for the drivers should be 1.6v according to the table conversion.

the table says
full step without jumpers multiply by 70%
1/16 step with all the jumpers is not modified anything would be 1.6v but I think that 1.6v for the drivers is a lot of voltage what I would like to know is if someone who has an A20M can take the voltages to the drivers and I can happen because mine are bad