One of the worst things in experimental science is having data that is inconclusive. However, something more insidious is when you equipment fails and conspires against you. I say "conspires" because at times I think we'd all swear there's some evil genius inside the machine purposefully twarting our efforts.

The current manifestation of this "entity" was causing us to lose the motor positions and alignment of our diffractometer (the giant green-aqua thing we use to take x-ray scattering data).

These are the works of man, this is the sum of our ambition : To make this little motor turn (in a known, reliable, repeatable fashion.






I spent much (too much) of the last day getting this little motor to spin properly. In the end we had two different mistakes compounding each other. Having two issues concurrently makes life more difficult because the cause becomes more difficult to identify. A typical problem solving approach to this is to first ask, "is there anything known to commonly fail that we should check first, or does the way it's failing indicate a particular problem?" Assuming that doesn't work (it didn't), the next phase is to proceed methodically through the rest of the parts, removing them from the list of possibilities. The problem here, is that with failure in two different areas, the above method doesn't exactly work.

Eventually we figured things out, but it was painfully long. I'll spare you the details, but we were running our motor at too high of a power, causing occasional jams, and our connection coupling from the motor would occasionally lose contact when one of the other motors was in motion. sigh...

For posterity's sake I should reproduce something here. After checking all over the web I could not find this information for the wiring of a particular model/kind of motor. So, after figuring out how a 4-phase motor should work, plenty of measurements with a multi-meter, and a bit of cursing similar (but different) wiring identification schemes, I finally got it. For a 4-phase (four-phase) Slo Syn synchronous stepping motor, model M061 - CE08 (made by Superior Electric) the connection wiring is as follows.

Label on the Motor : A,B,C,D,E,F,G,H
Matching common female connector : 1,2,3,4,5,6,7,8 (there's only one orientation here)
Using the standard 8 wire bundle (though any will do)
Connecting to a standard stepper-motor plug connector (male).


Motor Letter, Motor Connector (wire color) - stepper male connector plug letter
B,2 (red) - to A
H,8 (red/white) - B
D,4 (green) - C
F,6 (green/white) -D
G,7 (black) - E
A,1 (white) - F
E,5 (orange) - H
C,3 (black/white) - J

W & T short together
U & X short together

We short W&T, U&X because we use software limits on the motors, not hardware limits on the machine.

On the motor itself, the phase pulse out/return pairs are :
A/H - phase 2
B/G - phase 1
C/F - phase 3
D/E - phase 4

Hopefully google will pick that up for the next time someone needs that information.