so i got this motor from a moving projector. it has four pins, but when i checked with a multimeter i noticed that there is a connection between each two pins i touch. opening it up reveals that the two coils are connected (as seen A B C, but no D, looking closely i think there is a copper strip in th pcb connecting them). how does this motor work?
I have a pair of motors from a disk pack (early 80’s?), which are 3 pole with star wiring and a center tap, at least that’s what I worked out. Mine are marked Rapidsyn OV-03AF, 20v
Measure the coils with a multimeter… (v.low resistance setting), you should see a centre tap with three identical coils (resistances) on the other three lines… that is what I saw.
Googling produced no real matches for this type of motor, very little info at all…
… and at that point I gave up and used a conventional NEMA motor + stepstick.
I did entertain the idea of building my own controller with a AT328p (teensy, uno, etc) controller to run them via PWM and a whole bunch of mosfets on pwm pins, but to do them justice it would need a +20, 0, -20 volt supply, plus somewhat cumbersome circuitry for the mosfets on the low side. I decided that life is too short…
Three phase stepper?
Do not let the 6 wire confuse you.