RE: [CAD_CAM_EDM_DRO] automotive alternator as a Stepper Motor

i did a web search on the topic, and found that by.... doing...something...
darn, didn't bookmark it, now i can't find it. but it claimed that by doing
something you could get 42 steps/rev out of one, and told to put a 4-8 amp
headlight in the curcuit to keep the motor from burning... i didn't bookmark
it, maybe someone else can find it---dave L.

-----Original Message-----
From: Jon Elson [mailto:elson@...]
Sent: Wednesday, July 31, 2002 1:43 PM
To: CAD_CAM_EDM_DRO@yahoogroups.com
Subject: Re: [CAD_CAM_EDM_DRO] automotive alternator as a Stepper Motor


Doug Fortune wrote:

> I found this interesting note on an Australian website:
> Anyone have an idea how this might work?
>

Badly, very very badly! You would get something like 12 steps
per revolution, the inductance would be hideous, and it would
take a 3-phase drive, rather than 2/4 phase. Also, you'd need to
supply constant current to the rotor field, about 14 V at 2 A
or so. These units might make better 3-phase servo motors
with a somewhat more complex drive system. They would perform
about as well as a similar sized PM brushless servo motor, except
that they were not designed as servo motors, and so torque and velocity
ripple might be pretty high.

If you want a brushless servo drive, I suggest you watch eBay for a
commercial unit designed from the ground up for this use.

Jon


Addresses:
FAQ: http://www.ktmarketing.com/faq.html
FILES: http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/files/

OFF Topic POSTS: General Machining
If you wish to post on unlimited OT subjects goto:
aol://5863:126/rec.crafts.metalworking or go thru Google.com to reach it if
you have trouble.
http://www.metalworking.com/news_servers.html

http://groups.yahoo.com/group/jobshophomeshop I consider this as a sister
site to the CCED group, as many of the same members are there, for OT
subjects, that are not allowed on the CCED list.

NOTICE: ALL POSTINGS TO THIS GROUP BECOME PUBLIC DOMAIN BY POSTING THEM.
DON'T POST IF YOU CAN NOT ACCEPT THIS.....NO EXCEPTIONS........

Post messages: CAD_CAM_EDM_DRO@yahoogroups.com
Subscribe: CAD_CAM_EDM_DRO-subscribe@yahoogroups.com
Unsubscribe: CAD_CAM_EDM_DRO-unsubscribe@yahoogroups.com
List owner: CAD_CAM_EDM_DRO-owner@yahoogroups.com, wanliker@...
Moderator: jmelson@... timg@... [Moderator]
URL to this group: http://groups.yahoo.com/group/CAD_CAM_EDM_DRO
bill,
List Mom
List Owner



Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/