Mitsubishi Electric MELSERVO-J4 Series Instruction Manual page 162

Method -2 and -34 (Count type home position return)
For the count type home position return, after the front end of the proximity dog is detected, the position is
shifted by the distance set in the travel distance after proximity dog. Then, the first Z-phase is set as the home
position. Therefore, when the on-time of the proximity dog is 10 ms or more, the length of the proximity dog
has no restrictions. Use this home position return type when the dog type home position return cannot be
used because the length of the proximity dog cannot be reserved or other cases.
The following figure shows the operation of Homing method -2. The operation direction of Homing method -34 is opposite to
that of Homing method -2.
Statusword bit 10
Target reached
Statusword bit 12
Homing attained
Forward
rotation
Servo motor speed
Reverse
rotation
Z-phase
DOG (Proximity dog)
Controlword bit 4
Homing operation start
*1 After the front end of the proximity dog is detected, if the distance after proximity dog is traveled without reaching the creep speed, [AL.
90] occurs. Set the travel distance after proximity dog enough for deceleration from the home position return speed to the creep speed.
• When a home position return is started from the proximity dog
Servo motor speed 0 r/min
Reverse
rotation
After retracting to before proximity dog,
the home position return starts from here.
• When the movement is returned at the stroke end
Forward
rotation
Servo motor speed
0 r/min
Reverse
rotation
The home position return starts from here.
*1 This is not available with the software limit.
4 STARTUP
160
4.6 Home position return mode
ON
OFF
ON
OFF
Acceleration time
constant
Home position return speed
0 r/min
3 ms or shorter
Travel distance after
proximity dog
ON
OFF
ON
OFF
ON
OFF
Home position
return direction
Proximity dog
Home position
return direction
Proximity dog
Home position return start position
Deceleration time
constant
Creep speed
*1 Proximity dog
Home position return start position
Home position
shift distance
Home position return
position data
*1
Stroke end