"Underpowering" stepper motors

[ramonmaruko]

I mistakenly received 2.5A RMS/3.5A peak stepper motors instead of the 1.68A RMS/2.37A peak motors I intended to use. I have a Duet 3 Mini 5+ which can only provide 2A (peak), which is around 57% of the motors' rated current.

Since returning them would cost me a lot in shipping costs, is it okay to keep them running at 2A peak? I tested if the motors missed some steps using a modified version of this macro to work on my delta printer. Running that macro shows that it's not missing any steps although I am not sure how much I trust that since I tested down to 1A peak and it's not missing any steps. I have to go down to 500mA peak for it to fail homing...

[jay_s_uk]

@ramonmaruko you should be fine. Just make sure you cool the mini 5+

[Notepad]

@ramonmaruko From my experience, under powering motors tends to cause no issues as long as the requested torque is still within the required amount.

Higher amperage motors tends to just mean more headroom, so running them at 2A will be fairly similar to running 2A on your original intended motors. There will be differences, but generally it should be fine.

Only real world printing will be able to tell however.

[ramonmaruko]

@jay_s_uk @Notepad

I already have a 60 mm fan blowing over the drivers. Thank you for the responses. I have also done some test prints and have not found any problems so far. I have decided to keep the motors.