Mitsubishi Electric MELSEC Q Series Programming Manual page 398

6 POSITIONING CONTROL
(c) When it does not pass (zero pass signal: M2406+20n ON) the zero point
from home position return start to deceleration stop by proximity dog ON to
OFF, a minor error (error code: 120) will occur, a deceleration stop is made
and home position return does not end normally. When a distance between
home position return start position and home position is near and a zero
point is not passed, select the proximity dog method 2.
(d) If home position return is executed in the proximity dog ON, a major error
(error code: 1003) will occur, the home position return is not executed. Use
the proximity dog method 2 in this case.
(e) When home position return retry function is not set, if home position return is
executed again after home position return end, a minor error (error code:
115) will occur, the home position return is not executed.
(f) If in-position signal (M2402+20n) does not turn ON, home position return is
not ended.
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