On Mon, 17 Jan 2011 19:53:20 -0700, the renowned "Bob La Londe"
wrote:

I stopped by today to visit a buddy I haven't seen in a couple years to buy
a motorcycle trailer. He's been out of state taking care of his parents.
While I was there buying the trailer he handed me several other thing he was
getting rid of.

Some screw in lifting rings, a roll around cabinet with a nice flat top that
might be good for the small mill drill. Its old and heavier sheet metal
than modern cabinets.

He gave me a few other things (He's de junking) including a box of small
stepper motors. 3 are Nema 23 half tapped 2 phase 117oz, and 2 are nema 17
unknown force. Light duty stuff, but there was a Hobby CNC board and a
variety of heatsinks in the box as well. I thought I might make one of
those cheesy MDF frame gantries some guys make just for the fun of it with
these.

Now I was wondering if anybody had any idea how to figure out what DC
voltage and current setting would work well with these motors? I'm guessing
24-36 volts, and maybe 1-2 amps.

Modern circuits chop the power so you use a high power supply voltage
on a very low voltage motor. Here are the specs on Sherline's motors,
which are kinda midrange Nema 23s torque-wise, IIRC:

http://www.sherline.com/67127pg.htm

They are 2A at 3.2V, so would draw much less from a 24V supply with a
chopper driver.

Measure the winding resistance and see whether it looks like an ohm or
two.


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
Info for manufacturers: http://www.trexon.com
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