16.7.8 Count type front end reference home position return
This home position return method depends on the timing of reading DOG
(Proximity dog) that has detected the front end of a proximity dog. Therefore,
when a home position return is performed with the creep speed of 100 r/min, the
home position has an error of 6400 pulses (for HG series servo motor). The
higher the creep speed, the greater the error of the home position.
After the front end of a proximity dog is detected, when a home position return
ends without reaching the creep speed, [AL. 90] occurs. Set the travel distance
after proximity dog and the home position shift distance enough for deceleration
from the home position return speed to the creep speed.
Deceleration starts at the front end of a proximity dog. The position is shifted by the travel distance after
proximity dog and the home position shift distance. The position after the shifts is used as the home position.
The home position return is available independently of the Z-phase signal. Changing the creep speed may
change the home position.
(1) Device/parameter
Set input devices and parameters as follows.
Home position return mode
selection
MD0 (Operation mode selection 1)
DI0 (Point table No. selection 1) to
DI7 (Point table No. selection 8)
Count type front end
reference home position
return
_ _ _ 6: Select the count type (front end
detection/front end reference).
Home position return
direction
Refer to section 4.4.1 (2) to select the home
position return direction.
Refer to section 4.4.1 (2) to select the dog
input polarity.
Home position return speed
Set the rotation speed until the dog is
detected.
Set the rotation speed after the dog is
detected.
Home position shift distance
Set this to shift the home position, which is
specified after the front end of a proximity dog
is passed.
Travel distance after
proximity dog
Set the travel distance specified after the front
end of the proximity dog is passed.
Home position return
acceleration/deceleration time
constant
Use the acceleration/deceleration time
constant of point table No. 1.
Home position return position
data
Set the current position at the home position
return completion.