I’d like to drive a very small nema 8 motor and I was wondering if I can set the current to below 0.1A.
I’m running a pick and place machine on Smoothieboard v1.1 5XC-R and at the moment I’ve set the motor that moves the head up and down to 0.1A (on 24V) and it works fine.
The head motor that rotates the parts is tiny nema 8 rated at 5v and 0.6A but I’d like to keep it very cool as my mount is 3D printed and would distort if it gets hot, it has very little load on it so I think it would work on a very low current, I’m just wondering how low I could go. What is the lowest current and what resolution does the Smoothieboard work to?
You should set current at the exact value your stepper is rated for. Low currents are not an issue.
If it heats up ( which it should, it’s expected to ), add a fan there, or isolate it from it’s holder with an adequate material.
At the moment I don’t have the option to cool the motor and I’d just like to get things working to test it. When I modify everything after getting it all working I may make those changes as I’m sure it would help reliability.
I would in any case like to test to find what current I can go down to and not loose steps as it is easier to change the software that modify the hardware and there would be no point in running it hot at 0.5A when it works just as well at 0.2A.
I would still like to know what the lowest current I can use is and what resolution the config uses, for example is there a difference between setting 0.1A or 0.09A.
The values can go from 0 to 2A, and there are 1024 increments between them.
This is a current setting however, there is no way it is every going to matter if the value is 0.1 instead of 0.09, resolution isn’t a factor in this problem, at all.
The lowest current is 0, but setting it close to 0 is going to make the motor too weak to use.