[Talex]

Hi,

I purchased a MC433 4axis unipolar control board from SOC Robotics MC433 Stepper Motor Controller - actually their ebay store.
This was back in 2008 I believe, and I stopped there. Now I want to resume my CNC build and need to select some motors.
I've read the documentation but I am puzzled by the allowable motor voltage.
In the documentation it says that motor voltage is 8-35v. What does that mean exactly? Because most motors I see have a voltage range of 3-7v. For example : Wholesale-High quality ! NEMA 23 for 270 oz-in CNC stepper motor /3.0A Mill Cut | eBay
Since the voltage is lower than that indicated on the board, does that mean this board cannot drive it?

That's it for now.
Thanks,
-Alex

[Talex]

Ok. I believe this article http://www.selene.co/Blog/2011/07/st...ges-explained/ answers my question about stepper voltage and controller voltage.

[vladdy]

the mc433 board doesn't seem to drive steppers past the size of nema 17 ....at least I can't

[joeavaerage]

Hi,
uni-polar drives tend to be used on small motors. The drive electronics a very simple and cheap and so are favoured by manufacturers.
They tend to be lower performing with a given voltage supply than bi-polar drives. As a consequence they uni-polar drives tend to be used
with low speed, low torque steppers, maybe printers and that sort of thing, where cheap is, as, or more important than performance.

Steppers for CNC axis motors must perform at their very best to be any good at all. Thus just about ALL steppers intended for CNC axis
motors are bi-polar.

Craig