Re: [CAD_CAM_EDM_DRO] Re: stepper driver-transformer sizing question

On Wednesday 31 December 2003 15:10, Scott Riddle wrote:

> My application is not
> even going to have 1 of the steppers ever make a full rev. It will
> just rotate back and forth about 120°. I see what you mean about
> gearing to get a better torque advantage and more RPM's on the motors
> but I think this little project shouldn't require any reduction.

ahh right, rotating an egg! .. ok .. so 1) the motor is way, way over the top
already :) .. but gear it down as I suspect you want the accuracy mor than
the power as well, you'll find the thing much smoother and less overshoot
geared down ..

> On Ebay I found a bunch of DC power supplys (I used search words:
> pyramid power supply). They put out around 15V and 10-25A depending
> on which model you get. Would these be good or should I look for a
> power supply at around 40V and at least 4A?

for rtoating and egg? ... hmm personally, I'd put those motors on a shelf,
find something about 1/4 of the size (like 500ma max) and use that ... a
motor with 3A windings is way, way over the top. If you want to try it I'd
just find any power supply of 24V and and amp or so at most. theres no way
youll ever draw more rotating an egg!! Seriously .. you are talkign flea
power here infact if your drives will run off 12V a plug-top 12V adapter
might even have enough power ...

for that size of task smoothness is more important than power .. just get an
old inkjet printer or a scanner and you'll find enough small bits and pieces,
belts cogs and motors plenty big enough for the task .. and a power supply
too, al in the same box :)


--
Redpoint Consulting Limited

Real Solutions for a Virtual World
http://www.redpoint.org.uk