Mitsubishi FREQROL-SFJ Maintenance Manual page 116

(13) Speed can be controlled normally, but spindle cannot be
stopped in position (oriented sindle stop) . . . . .
Cause
Speed can be de-
creased to "ori-
stop" speed, but
motor does not
stop.
Oriented spindle
stop position in
forward rotation
deviates from
oriented stop po-
sition in reverse
rotation (during
multipoint ori-
ented spindle
stop).
Checkup
Check if position feedback
encoder or magnesensor
is in good condition.
Run the motor under speed
control to check position
feedback signal.
Check the signals on the
'following check pins of
cards SF-ORJ, DAJ and TLl
while the motor is running
forward.
(Mark pulse)
Check on the following pins
of card SF-ORJ, DA1 and TLJ
while the motor is running
forward.
or CONB(10)
Backlash in encoder is
large.
Remedy
Replace the posi-
tion detector or
replace card SF-CR;
DAJ or TLJ.
i
Reduce the back-
lash.