Stepper Voltage, does it really matter?

I'm building my first cnc mill, and have been picking steppers up from here and there. I now have around 12 steppers, of which 4 looks pretty good. (Large, cool looking, 200steps/rev) :o)

When I connect my psu from my childhood race-track (6V, 10VA) they all deliver a very good holding torque, while not running warm, so I think they'll all run resonably with that psu.

The thing is... On the two largest steppers are a small sticker that says "VOLT DC 1.8 AMP DC 4.8A/PH" and one of the smaller says "1A/PH" no voltage on that one., and the last says "6.0V/PH, 1.2A/PH" How do I decide what powersupply to use?

I also have a 300VA 12V PSU and a 150VA 12V psu. What combination will give me the best performance, and do I need to limit the current?

What else should I look out for?

Thanks.

Michael




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