Mitsubishi Electric MELSERVO-JE Instruction Manual page 91

6. SERVO MOTOR DRIVING
(e) Method -6 and -38 (dog type rear end reference home position return)
The following figure shows the operation of Homing method -6. The operation direction of Homing
method -38 is opposite to that of Homing method -6.
ON
Statusword bit 10
Target reached
OFF
ON
Statusword bit 12
Homing attained
OFF
Forward
rotation
Servo motor speed 0 r/min
Reverse
rotation
ON
DOG (Proximity dog)
OFF
ON
Controlword bit 4
Homing operation start
OFF
Note. After the front end of the proximity dog is detected, if the rear end of the proximity dog is detected without reaching the creep
speed, [AL. 90] occurs. Revise the length of the proximity dog or revise both the home position return speed and creep speed.
Servo motor speed
After retracting to before proximity dog,
the home position return starts from here.
When a home position return is started from the proximity dog
Servo motor speed
The home position return starts from here.
Note. This is not available with the software limit.
POINT
This home position return type depends on the timing of reading DOG (Proximity
dog) that has detected the rear end of the proximity dog. Therefore, when the
creep speed is set to 100 r/min and a home position return is performed, the
home position has an error of ± (Encoder resolution) × 100/65536 [pulse]. The
higher the creep speed, the greater the error of the home position.
Acceleration time
constant
Home position return speed
10 ms or shorter
Home position
return direction
0 r/min
Reverse
rotation
Home position
return direction
Forward
Home position return start position
rotation
0 r/min
Reverse
rotation
When the servo motor returns at the stroke end
Deceleration time
constant
(Note) Proximity dog
Proximity dog
Home position return start position
Proximity dog
6 - 26
Travel distance after proximity dog
+
Home position shift distance
Creep speed
Home position return
position data
Stroke end (Note)