Mitsubishi A1SD75P1-S3, Руководство пользователя

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MELSEC-A
8 ZERO POINT RETURN CONTROL
8.2.2 Machine zero point return method
The method by which the machine zero point is established (method for judging the
zero point position and machine zero point return completion) is designated in the
machine zero point return according to the configuration and application of the
positioning method.
The following table shows the six methods that can be used for this zero point return
method.
(The zero point return method is one of the items set in the zero point return
parameters. It is set in " Pr.45 Zero point return method" of the basic parameters for
zero point returns.)
Pr.45
Zero point return method
Operation details
Near-point dog method
Deceleration starts by the OFF ON of the near-point dog. (Speed is reduced
to "
Pr.49
Creep speed".)
The operation stops at the first zero point signal after the near-point dog turns
from ON OFF. When a "deviation counter clear output" is completed, the
machine zero point return is completed.
Stopper method 1)
The stopper position is regarded as the zero point.
After the deceleration starts by the OFF
ON of the near-point dog, the
machine presses against the stopper at the "
Pr.49
Creep speed" and stops.
The machine zero point return is regarded as completed on completion of the
deviation counter clear output provided after "
Pr.51
Zero point return dwell time"
passed after stoppage.
Stopper method 2)
The stopper position is regarded as the zero point.
After the deceleration starts by the OFF
ON of the near-point dog, the
machine presses against the stopper at the "
Pr.49
Creep speed" and stops.
The machine zero point return is regarded as completed on completion of the
deviation counter clear output provided after the zero point signal
is detected
after stoppage.
Stopper method 3)
The stopper position is regarded as the zero point.
The machine starts at the "
Pr.49
Creep speed" from the beginning, then presses
against the stopper at the "
Pr.49
Creep speed" and stops.
The machine zero point return is regarded as completed on completion of the
deviation counter clear output provided after the zero point signal
is detected
after stoppage.
Count method 1)
The deceleration starts by the OFF ON of the near-point dog, and the
machine moves at the "
Pr.49
Creep speed".
The machine stops at the zero point signal after moving the distance set in the
"
Pr.52
Setting for the movement amount after near-point dog ON" from the near
point dog OFF ON position. When a "deviation counter clear signal output" is
completed, the machine zero point return is regarded as completed.
Count method 2)
The deceleration starts by the OFF ON of the near-point dog, and the
machine moves at the "
Pr.49
Creep speed".
The machine moves the distance set in the "
Pr.52
Setting for the movement
amount after near-point dog ON" from the near point dog OFF ON position,
and stops at that position. The machine zero point return is then regarded as
completed.
*: The zero point input signals of the AD75 in each zero point return method are described below.
Near-point dog method and count method (1): One-pulse signal output per each motor revolution
(Z-phase signal output from drive unit, etc.)
Stopper stop method (2), (3): Signal output upon detection of contact with stopper
(Supplied from an external device)
REMARK
Creep speed
The stopping accuracy is poor when the machine suddenly stops from high
speeds. To improve the machine's stopping accuracy, its must change over to a
low speed before stopping. This speed is set in the " Pr.49 Creep speed".
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