5. HOW TO USE THE PROGRAM 
5 -  47 
 
5.4.7 Dog type rear end reference home position return 
 
POINT 
 
This home position return method depends on the timing of reading DOG 
(Proximity dog) that has detected the rear end of the proximity dog. Therefore, 
when a home position return is performed at a creep speed of 100 r/min, the 
home position has an error of 200 pulses (for HG series servo motor). The 
higher the creep speed, the greater the error of the home position. 
 
Deceleration starts from the front end of the proximity dog. After the rear end is passed, the position is 
shifted by the travel distance after proximity dog and the home position shift distance. The position after the 
shifts is set as the home position. The home position return is available independently of the Z-phase signal. 
 
(1) Device/parameter 
Set input devices and parameters as follows: 
 
Item  Device/parameter to be used  Setting 
Automatic operation mode of 
the program method 
MD0 (Operation mode selection 1)  Switch on MD0. 
Dog type rear end reference 
home position return 
[Pr. PT04] 
_ _ _ 5: Select the dog type (rear end 
detection/rear end reference). 
Home position return 
direction 
[Pr. PT04] 
Refer to section 5.4.1 (2) to select the home 
position return direction. 
Dog input polarity  [Pr. PT29] 
Refer to section 5.4.1 (2) to select the dog input 
polarity. 
Home position return speed  [Pr. PT05] 
Set the rotation speed specified until a dog is 
detected. 
Creep speed  [Pr. PT06] 
Set the rotation speed specified after a dog is 
detected. 
Home position shift distance  [Pr. PT07] 
Set this to shift the home position, which is 
specified after the rear end of the proximity dog is 
passed. 
Travel distance after proximity 
dog 
[Pr. PT09] 
Set the travel distance after the rear end of the 
proximity dog is passed. 
Acceleration time constant of 
home position return 
[Pr. PC30] 
The acceleration time constant set for [Pr. PC30] 
is used. 
Deceleration time constant of 
home position return 
[Pr. PC31] 
The deceleration time constant set for [Pr. PC31] 
is used. 
Home position return position 
data 
[Pr. PT08] 
Set the current position when the home position 
return completed. 
Program 
DI0 (Program No. selection 1) to 
DI3 (Program No. selection 4) 
Select a program containing a "ZRT" command, 
which performs the home position return.