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5. OPERATION
5.6.8 Count type front end reference home position return
POINT
This home position return method depends on the timing of reading Prox imity
dog (DOG) that has detected the front end of a proximity dog. Hence, if a
home position return is made at the home position return speed of 10 0r/min,
an error of 400 pulses will occur in the home position. The error of the home
position is larger as the home position return speed is higher.
The position where the axis, which had started deceler ating at the front end of a proximity dog, has moved the
after-proximity dog moving distance and hom e position shift distance is defined as a home position. A home
position return that does not depend on the Z-phas e signal can be made. The home position may chan ge if the
home position return speed varies.
(1) Devices, parameters
Set the input devices and parameters as indica ted below.
Item Device/Parameter used Description
Automatic/manual selection (RYn6) Turn RYn6 ON.
Manual home position return mode
selection Point table No. selection 1 to 8
(RYnA to RYnE, RY(n 2)3 to RY(n 2)5)
RYnA to RYnE, RY(n 2)3 to
RY(n 2)5 are turned off.
Remote register-based
position/speed setting
(Only when two stations are
occupied)
Position/speed specifying system selection
(RY(n 2)A) Turn RY(n 2)A ON.
Count type dog front end reference
home position return Parameter No.PC02 6: Select the count type dog
front end reference.
Home position return direction Parameter No.PC03 Refer to section 5.6.1 (2) and select the
home position return direction.
Dog input polarity Parameter No.PD16 Refer to section 5.6.1 (2) and select the
dog input polarity.
Home position return speed Parameter No.PC04 Set the speed till the dog is detected.
Creep speed Parameter No.PC05 Set the speed after the dog is detected.
Home position shift distance Parameter No.PC06
Set when the home position is moved
from where the axis has passed the
proximity dog rear end.
Moving distance after proximity dog Parameter No.PC08 Set the moving distance after the axis
has passed the proximity dog rear end.
Home position return acceleration/
deceleration time constants Point table No.1 Use the acceleration/deceleration time
constant of point table No.1.
Home position return position data Parameter No.PC07 Set the current position at home
position return completion.