Re: Motor and Power Supply Questions

Hi Ralph,

If you are going for the maximum, you should be able to get EXACTLY
THE SAME transformers and connect them in series. This would double
the voltage output. MATCHED transformers are a must.

You only get the amperage rating of one transformer. so your 5.77
amps would be 5.77, not 11.54.

Your 26 VAC would become 52 VAC and after your rectify you would be
at 72 volts. 17 times the motor voltage is pretty good.

Dave

--- In CAD_CAM_EDM_DRO@y..., "rawen2" <rawen2@w...> wrote:
> Hi group,
>
> I'm still in the planning stages of converting a benchtop mill to
> CNC. Special thanks to Mariss for explaining in detail how to
> calculate motor sizes. According to his calculations the minimum
> torque would need to be greater than 300oz/in.
>
> I found some used stepper motors - Applied Motion brand; NEMA 34;
> 450oz/in; 4.27V 3.5A; 1.22 ohms; inductance 7.0 mH; 200 steps/rev;
> price $50 ea. The voltage seems to be higher than what I see
others
> using. Would these work well? If not, what problem(s) would I
> encounter? I will be using API brand CMD-260 motor drivers because
> they were the least $$ I could find.
>
> I also found a couple of toroid transformers.
> 1. 36 VAC output @ 2A.
> 2. 26 VAC output @ 5.77 A.
> If my math is correct #1 will put out roughly 50 VDC after
> rectification and #2 will put out about 36 VDC but with greater
> amperage. Which one would be better or are they both too small?
> From what I've read I assume that higher voltage would be better.
>
> Thanks for any help.
>
> Ralph