Re: 8 wire steppers, parallel. series or single winding?

John,

Your present configuration, windings in parallel, is the best for
getting the most speed out of the motors. Using a single winding of
each phase would have close to the same performance, but offer no
advantages. Running with the windings in series will provide more low
speed torque at the same driver current setting, but will have poorer
performance at high speeds.

Speed improvements could come from higher drive current, if the
motors and drivers are rated for it, or from higher supply voltage to
the driver, within its rating. These comments apply to a "bipolar,
switching" driver, which is the case for the Camtronics drivers that
I believe you are using. Some minor improvement could also result
from different motor current recirculation modes, something I do not
think is easily modified on the Camtronics drivers.

Your problem could also be due to ragged pulse timing which is more
of a problem at higher speeds. You could verify this by trying your
system with a higher performance computer or with a system that
utilizes an external pulse timing generator. Alternatively, a test
with Gecko 210 could help determine if this is the case. It has a
phase-locked loop pulse multiplier and microstepping which will
smooth out the ragged timing before the motor sees it.

Good luck,
Steve Stallings

--- In CAD_CAM_EDM_DRO@y..., "John Guenther" <j.guenther@v...> wrote:
> I know this has been addressed before but here goes any way. I
have some 8
> wire stepper motors, Pacific Scientific NEMA 23's, and I would like
to know
> what configuration will give the highest speed. I am currently
running them
> in a parallel configuration which gives plenty of torque but seems
to limit
> top speed. Would I get higher speed by running single winding per
phase at
> the cost of torque?
>
> Thanks
>
> John Guenther
> Sterling, Virginia