Mitsubishi A1SD75M1, User Manual

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MELSEC-A
8 ZERO POINT RETURN CONTROL
8.2.4 Zero point return method (2): Near-point dog method 2)
When the zero point is passed between a machine zero point return start and
deceleration to a stop by the near-point dog ON to OFF, the operation outline of the
zero point return method "near-point dog method 2)" is the same as that of the zero
point return method (1) "near-point dog method". (Refer to section 8.2.3.) The following
shows the operation outline of the case where the zero point is not passed.
Operation chart
1)
The machine zero point return is started.
(The machine starts acceleration designated in "
Pr.53
Zero point return acceleration time selection" in the direction
designated in "
Pr.46
Zero point return direction", and moves at "
Pr.48
Zero point return speed".)
2)
At detection of the near-point dog ON, the machine decelerates to "
Pr.49
Creep speed", and then moves at the creep
speed.
3) At detection of the near-point dog ON, the machine decelerates to a stop.
4)
After stopping, the machine moves by the amount of one servomotor revolution at "
Pr.48
Zero point return speed" in the
direction opposite to the designated zero point return direction.
5)
The machine moves at " Pr.48 Zero point return speed" in the designated zero point return direction, and completes the
machine zero point return in the position of the first zero point after near-point dog ON to OFF. (At this time, the machine
does not decelerate to "
Pr.49
Creep speed" when the near-point dog turns from OFF to ON.)
Zero point return direction
Zero point return speed
Creep speed
Speed
Near-point dog
ON
OFF
Pr.48
Pr.49
Zero point
1)
2)
3)
4)
5)
Zero point not passed
Fig. 8.4 Operation performed when the zero point is not passed in the near-point dog method 2)