Closed loop stepper motors on duet2
Davy last edited by
Hello, I occasionally read on the forum. Now I have a question and Ryan from Ooznest told me to place it here.
I try to connect closed loop stepper motors (2phase) to a duet2 with an expansion breakout board. Before I had normal stepper motors with external drivers on the duet.
When I use the jog commands (G0) with the buttons it works. When I use a other command,like homing (G1), it goes wrong. Stuttering movements and the distance is no longer correct. The distance is ok when i use the buttons.
If i set the closed loop running off with a switch, same result.
The strange thing is that the driver does not give an alarm for the missed steps. So the driver does not see the missed steps.
When I block the motor, the driver go in alarm because of missed steps, so that works.
I tested with a 3phase motor/driver, also closed loop and this works fine.
I tested the 2phase motor with a normal driver and this works also fine. So the problem is the driver or the settings?
G1 command with higher speed works.
So it's somewhere a setting, but which one? I have no idea.
The seller gave me software to program the driver. Here I can see that if I give 5000 pulses with a speed of 15000,
the driver also gives 5000 pulses. But when I give 5000 pulses at speed 1500, then only 800 pulses are counted.
So only higher speed as 12000 works.
I'm using following motor and drivers:
2phase LC57H2100 from Lichuan
LCDA257S driver from Lichuan
Shenzhen Xinli Chuan Electric Co., Ltd.
bought on Aliexpress.
Motor encoder resolution is 1000 (PPR)
Step angle 1.8°
Does anybody have experience with this? Or an idea how to solve this?
Sorry for my english.
Most external drivers need slower step pulse timings than RRF provides by default. Consult the stepper driver manual for details, and use the M569 T parameter to configure them in RRF.
Davy last edited by
Does that mean in that i must set a T parameter with higher numbers? Any idea how high? I'm a newbee in this material