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13. POSITIONING MODE
13.6.9 Count type front end reference home position return
POINT
This home position return method depends on the timing of reading the
proximity 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
100r/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 decelerating at the front end of a proximity dog, has moved the
after-proximity dog travel distance and home position shift distance is defined as a home position. A home
position return that does not depend on the Z-phase signal can be made. The home position may change if the
home position return speed varies.
(1) Devices and parameters
Set the input devices and parameters as indicated below.
Item
Device/Parameter used
Description
Manual home position return
mode selection
Automatic/manual selection (MD0)
Turn MD0 ON.
Point table No./Program No.
selection 1 to 3 (DI0 to DI2)
Point table method: Select the home position return
mode by turning OFF DI0, DI1 and
DI2.
Program method: Select a program that has the home
position return "ZRT" command.
Count type dog front end
reference home position return
Parameter No. PE03
6: Select the count type dog front end reference.
Home position return direction
Parameter No. PE03
Refer to section 13.6.1 (2) and select the home position
return direction.
Dog input polarity
Parameter No. PE03
Refer to section 13.6.1 (2) and select the dog input
polarity.
Home position return speed
Parameter No. PE04
Set the speed till the dog is detected.
Creep speed
Parameter No. PE05
Set the speed after the dog is detected.
Home position shift distance
Parameter No. PE06
Set when the home position is moved from where the
axis has passed the proximity dog front end.
Travel distance after proximity
dog
Parameter No. PE09
Home position return
acceleration/deceleration time
constants
Parameter No. PE07
Set the acceleration/deceleration time constants during
a home position return.
Home position return position
data
Parameter No. PE08
Set the current position at home position return
completion.