Re: can six wire bipolar be wired parallel?

Hi Rick,
Without opening the motor, your six wire motor can typically be
wired three differnet ways:
Unipolar
Bipolar half winding.
Bipolar series winding.
Thus it can not be wired for bipolar parallel

With bipolar half winding, you will have the same current requirments
as the unipolar rating. With bipolar series, you would use half that
amount.

For example a stepper rated at 4 amps unipolar could be run bipolar
half winding at 4 amps as well (the wire inside can handle 4 amps).
However if you want to run series. The number now becomes 2 amps.
This amperage rating will get you the same torque as the
unipolar/half winding rating. Since the wires can handle more
current, you *could* run more current through them, and manufacturers
often take the unipolar rating, multiply by .71 to get the number to
use, which in this case would be about 2.8A (more current, more
torque... to a point). Note however, that at this point the motor
core would be "saturated". This is fine if you want to run FULL step
mode, but bad if you want to run with a microstepping drive. This
much current will smear out any smoothing advantage microstepping
produces leading to a rougher system. In this -series- winding
example, somewhere between [2.0A and 2.8A] would be the optimal
current level for the motor to acheive most torque while still
getting the benefits of microstepping.

Jeff

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "rllalonde2000"
<alalonde@s...> wrote:

> I'd sure appreciate it if anyone could answer for me if a six wire
> bipolar stepper can be wired for parallel. Thanks.
>
> Rick L.