Re: 8-wire stepper motor

Sorting out the wires on an 8-wire stepper motor:

Dave, I make no representations that this is correct, or safe, and
I'd love to hear feedback from others, but on small stepper motors -
say NEMA size 23 120oz steppers, I just sit down with a 6-volt
lantern battery and power up successive pairs. What happens is that
you'll first discover which one of each pair should be a common
ground because the motor will step in the same direction when you've
randomly selected the correct polarity for each. Restated, if two of
the pairs (keeping track of which one of each pair you hooked to
ground on the battery) turned the motor clockwise, and the third pair
that you try turns the motor one step counterclockwise, then switch
the third pair (ground verse positive) and move on to the final
pair. After you've figured out the ground for each pair using this
method you then sequence the pairs until you discover which sequence
of pairs causes the motor to step smoothly. There will only be one
sequence of pairs (again using the grounds the you identified in step
one)that cause the motor to move smoothly.

Note: - each of these "test" causes the motor to only move one step,
but that is enough motion to be able to correctly identify the
pairs. Also, this whole process takes less time that it took to
write this e-mail.

Let me know if this works for you, and I'd love to hear any comments
from others on this method.