I'm using a TMCM-102 module to drive a Haydon Kerk stepper motor. The motor has a maximum coil current of 1.5 A, the TMCM-102 is designed for motors up to 3.5A coil current.
I just can find combinations of speed/current which returns a StallGuard value of 3-4 (in TMCL-IDE), so I set the StallGuard Threshold to 5 to find the mechanical stop. The problem is, that sometimes the StallGuard value 5 is read during reference search and the motor stops. If I set the Threshold to 6, the motor runs into the mechanical stop without stoping. Now I'd like to set up the TMCM-102 for motor currents up to 1.5A to get StallGuard values in a better range. I've read a lot in the manuals and datasheets. I'll change the value of RSH, RSA and RSB to 0.15 ohms. Would this work? Or is it not possible to get better StallGuard values by changing the sense resistors? Did I forget anything important? What would you suggest to get useful StallGuard values?
Thank you for your help.