MPI <4G63>
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Troubleshooting
13D-86
Standard wave pattern
Stepper
motor
control
signal
wave
pattern
(V)
30
20
10
The wave pattern
appears for an
instant, but soon
disappears.
Point B
Coilreverse electromotive
force (Approx. 3
u
10 V)
Point A
Induced electromotive force
from the motor turning
Time
Wave pattern Observation Points
Check that the standard wave pattern appears when the stepper motor is operating.
Point A: Presence or absence of induced electromotive force from the motor turning (Refer to the abnormal
wave pattern).
Contrast with standard wave pattern
Probable cause
Induced electromotive force does not appear or is extremely small.
Motor is malfunctioning
Point B: Height of coil reverse electromotive force
Contrast with standard wave pattern
Probable cause
Coil reverse electromotive force does not appear or is extremely small.
Short in the coil