Mitsubishi A1SD75M3 User Manual page 344

8 ZERO POINT RETURN CONTROL
Restrictions
•
The system where the machine can move by the movement amount of more
than one servomotor revolution is required.
•
The system where the upper/lower limit stroke limit signal does not turn OFF
when the servomotor rotates one turn in the opposite direction following a stop
made when the designated condition holds after the near-point dog has turned
ON, is required.
Precautions during operation
(1) When the zero point return retry function is not set (" Pr.50 Zero point return
retry" setting is "0"), making a machine zero point return again after completion
of a machine zero point return results in an error "start at zero point" (error
code: 201).
(2) When a machine zero point return is started while the near-point dog is ON,
the machine starts at " Pr.49 Creep speed".
(3) The near-point dog must be kept ON while the machine decelerates from the
zero point return speed to " Pr.49 Creep speed".
(4) When the zero point is not passed between a machine zero point return start
and the near-point dog ON to OFF, do not touch the servomotor and
positioning system until the machine zero point return is completed.
(When the servomotor rotates one turn in the opposite direction, the AD75
waits until the in-position signal and zero speed signal of the servo amplifier
turn ON. If the servomotor or positioning system is touched in the status where
the stop position has not yet been reached, the in-position signal and zero
speed signal may turn ON due to the motor side load, rotating the servomotor
suddenly in the opposite direction and positioning the machine to the zero
point.)
(5) If the restart command is turned ON after the machine zero point return is
stopped by the stop signal, an error "zero point return restart not possible"
(error code: 209) occurs.
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MELSEC-A