Printronix L5000 Series Maintenance Manual page 206

Transfer elevator motor
This is a 2-phase 4-pole stepper motor. Its permanent magnet rotor rotates when pulse
signals, which are 90 out of phase, are applied to four electromagnets as shown
below. (One pulse provides a step angle of 1.8 .)
The transfer unit moves up or down when the shaft (cam shaft) of this motor rotates
180 (equivalent to 100 pulses) in the normal or reverse direction.
The motor drive sequence is indicated in the tables below.
(Forward rotation)
Pole A
Pole B
Pole C
Pole D
(Reverse rotation)
Pole A
Pole B
Pole C
Pole D
5–46
1 2
1 1
0 1
0 0
1 0
1 2
0 0
0 1
1 1
1 0
3 4
0 0
1 0
1 1
0 1
3 4
1 1
1 0
0 0
0 1
Principles of Operation