Setting driver current

[ataraxis 51]

Hi everyone!

I tried to adjust the driver current to 1.7A maximum since i installed a new stepper.

In order to do so, I measured the VREF and set it from 0.65V to 0.9V.

This is my calculation:

1.7A / 0.7 = 2.43A (since the A4988 limits to around 70%)

2.43A / 2.5Ohm = 0.97V (according to https://www.pololu.com/product/1182)

=> 0.9V for safety reasons...

The problem is, now the stepper seems to be more underpowered than before (way less torque!!)

Any ideas?

Thank you!

[ataraxis 51]

Is it maybe possible that the driver overheats that fast? It looks like the torque drops after around one minute nonstop extruding - very strange... will measure the temperature the next days. I cannot think of any other source for that problem. btw... it's the extruder motor!