Mitsubishi Electric MELSEC Q Series Programming Manual page 421

6 POSITIONING CONTROL
V
Home position
return start
(e) If the zero point is passed during deceleration, the nearest position of home
position signal (zero point) of home position return direction from
deceleration stop position is set as the home position.
Home position
Home position
return speed
return direction
Creep speed
4)
Home
position
3)
Proximity
dog
(f) Home position return retry function cannot be used in the scale home
position signal detection method.
(g) An error always occurs without the proximity dog in home position return
direction from home position return starting position, so that the proximity
dog is set before limit switch of home position return direction for making the
proximity dog overlap in limit switch like Fig. 6.44.
And, when home position return is executed in the proximity dog, an error
will occur if zero point is not in reverse direction of home position return from
home position return starting position.
(h) When there is only one zero point in the motor like linear motor, home
position return may not be ended if zero point is in the proximity dog. Set
zero point before the proximity dog.
(i) If the in-position signal (M2402+20n) is not turned ON, home position return
is not ended.
1) It travels to preset direction of home
position return with the home position return
speed, and a deceleration stop is made by
1)
the proximity dog ON.
2) After a deceleration stop, it travels to
reverse direction of home position return
with the home position return speed.
3) Home position signal (zero point) is detected,
and a deceleration stop is made. (The home
position signal (zero point) is passed during
deceleration.)
4) After a deceleration stop, it travels to preset
diresction of home position return with the
creep speed, the home position return ends
with the nearest position of home position
2)
signal (zero point).
External limit switch
Zero point
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