Re: APS stepmotor pinout sta

['Dan Legnini' <dan_legnini@qmgate.anl.gov>]

                      RE>APS stepmotor pinout standard             11/8/96

i mistakenly sent this reply last week only to pete, and didn't cc: the list,
so here it is:
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>From: Pete Jemian

>At the last meeting of the beam line controls group,
>there was a discussion about the APS standard for wiring
>up stepping motors.  

i was out of town at the last meeting, but claude from CARS called me and i
also discussed the issue with tim.

>It seemed at the time that two different 
>standards had emerged.

my understanding of the confusion is that our current agreement to agree on a
standard is not the same as what we said or distributed on various early
pieces of paper.  i made this point at the meeting in feb. when i last
presented the proposed standard.  all present agreed to go on with the
standard as proposed at that time, and to abandon the past quasi-standard(s). 
in particular, i made sure that the people present at the meeting knew that
this was not the same as what CARS has already done, since they've been using
elcos for a while, nor did it agree totally with information previously
distributed by BCDA.

>A group was going to look into the
>situation immediately and supposedly report back.

i know nothing about that.  who is in the group?  what have they found out?  

by definition the *APS* motor standard is what *we* say it is.  obviously, if
there is a standard out there adopted by the industry, then we would be
intelligent to use it.  i have not been able to find a standard which is in
use by the manufacturers i have dealt with.  slosyn appears to have a standard
which a lot of scientists and engineers know about, but when i called Leo at
ACS (vendor of step-paks) i found he wasn't designing his drivers to meet any
industry-wide standard, and wasn't much concerned with which way a motor
moved.  the response was similar when i talked to someone at Aerotech.

it is possible that there is a standard out there which has escaped me (us). 
if so, we may want to re-address this issue, but i doubt very much it will go
beyond the driver-motor connection level.  i believe we are attempting to
incorporate other elements of the motion control chain (controllers, encoders)
into *our* standard.

i told tim i would make another effort to determine if there really is a
standard in *wide* use by the *industry*, or by the vendors we use most.  if
anyone has information on this please contact me.

>What is _the_ APS standard (what wire color goes to what ELCO >pin) for
wiring ...

for now see:
http://www.aps.anl.gov/xfd/WWW/xfd/bcda/Documents/moconstd.html

and stay tumed...

dan