From: David L. Peterson
Subject: Re: 3 wire stepper motors
Date: Thu, 26 Sep 2002 22:46:57 -0500
Organization: netINS, Inc.
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On 26 Sep 2002 03:57:18 -0700, firstname.lastname@example.org (Ralph Seguin)
>I noticed at a surplus shop some Superior Electric NEMA 34 stepper
>motors, 120V, 0.3A, 50 oz-in, 3 wire.
>What is a 3 wire stepper motor?
>How does one drive them?
>I have a really small budget ($0 if you ask my wife :-), so I don't
>think I can afford all the nice servo and stepper stuff.
>I have a 3 axis stage with 10 TPI Acme screws on X and Y and a
>ballscrew on Z that I'd like to make into a little mini-CNC mill.
>I know that 50 oz-in is pretty low compared to some of the 150-250
>oz-in motors that I've seen, but those other motors are pricey.
>I was thinking of rectifying 120V AC to 120V DC and using that as a
>power source, or maybe rectifying 240V AC to DC. Is this a bad idea?
>Are these motors worth investigating, or should I save my pennies?
>Inexpensive source for kick ass motors, drives, controllers, ...? :-)
>Inexpensive source for power FETs?
>Inexpensive source for rectifiers?
>Inexpensive source for power diodes?
>rpseguin AT yahoo DOT com
I have a bigger superior electric 3 wire stepper motor (it's laying in
pieces by my feet right now) that I took apart a few weeks ago to see
if I could turn it into a regular stepper motor. After tracing out
the circuit board soldiered to all the coils I have to say that, yes,
they can be made into regular bipolar/unipolar motors relatively
easily. Is it worth it for a 50oz-in motor? Not for me, the one I
got is a 720 oz-in so I was thinking about it. :) If you have a
soldiering iron, and exacto blade, and some scraps of wire you can
make them into regular six wire steppers pretty easily. Looks like
you could ditch the circuit board completely and rewire the coils in
parallel to make it run on half the voltage, but that's take a lot of
patience and a pretty good understanding of what you are doing.