[APML] AC Synchronous Stepper Motor

[Mark Kaye <mark.kaye@sympatico.ca>]

    I am servicing a focuser from an RC scope that uses an AC synchronous 
stepper motor that runs off of 120 volts to move the secondary to focus the 
telescope.  The SS25 motor from Superior Electric has just three wires.  It 
turns a threaded shaft that moves the mirror in or out.  From the look of 
things, a simple pairing of two of the three leads (white appears to be 
common to red and black) to the power line should turn the motor in one 
direction or the other.  Unfortunately, the mechanism seized at some point 
and now the motor just stutters when I wire it the way I think it should be 
wired.  I am hesitant to do extensive experimentation at this point, after 
all it is 120 volts AC I am talking about here.
    I have done a pretty extensive web search and I finally found a page 
that makes reference to the family of motors that I think I am interested 
in.  As is usual in web searches, when I find the page that looks like it 
might have the information that I am looking for, I get a page not found 
error.  Can anyone point me in the direction of information on AC stepper 
motors or help me getting this thing to spin?
    Clear skies!
                MK

http://www3.sympatico.ca/mark.kaye/


--  APML Archives at <http://www.system.missouri.edu/apml/>  ---
                Unsubscribe at <majordomo@seds.org>