Delta ASDA-A3 Series User Manual page 418

ASDA-A3
Referencing the limit.
1.
This homing method uses the positive or negative limit as the reference point. When the
limit is detected, you can choose whether to look for the Z pulse and use it as the
reference origin. The searching result is the same regarless of where the start point is. The
ASDA-A3 always looks for the reference point according to the setting to correctly reset
the coordinates.
Motor
(a) Reverse to Z
(b) Go forward to Z
(c) Do not look for Z
Refer to the preceding figure for examples.
If you set the servo to look for the Z pulse in the reverse direction, the servo operates
(a)
at high speed (first speed setting) and then decelerates once it reaches the limit
(rising-edge triggered). Then the servo switches to low speed (second speed setting)
to look for the Z pulse in the reverse direction. When the servo finds the Z pulse, it
decelerates to a stop, completing the homing procedure.
If you set the servo to look for the Z pulse in the forward direction and the limit signal
(b)
at the start position is un-triggered (low, Start point 1), the servo operates at high
speed (first speed setting) and then decelerates once it reaches the limit (rising-edge
triggered). Then the servo switches to low speed (second speed setting) to look for
the Z pulse in the forward direction. When the servo finds the Z pulse, it decelerates
to a stop, completing the homing procedure. If you set the servo to look for the Z
pulse in the forward direction and the limit signal at the start position is triggered
(high, Start point 2), the servo returns to look for the rising-edge limit signal at low
speed (second speed setting). Once it is found, the servo starts to look for the Z
pulse and decelerates to a stop when it finds the Z pulse, completing the homing
procedure. In conclusion, the origin is at the same position after homing with the
same condition regardless of the location of the start point.
Start point
Start point 1
Start point
Z pulse
Limit signal
Limit
End
End
End
Motion Control
Start point 2
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