Mitsubishi Electric MELSEC Q Series Programming Manual page 415

6 POSITIONING CONTROL
(4) Cautions
(a) A zero point does not must be passed (zero pass signal: M2406+20n ON)
between turning on the power supply and executing home position return.
(b) Home position return retry function cannot be used in the stopper method 1.
(c) Set the torque limit value after reaching the creep speed for system.
When the torque limit value is too large, servo motors or machines may be
damaged after pressing the stopper. Also, when the torque limit value is too
small, it becomes the torque limiting before pressing the stopper and ends
the home position return.
(d) If the home position return is executed again after home position return
completion, a minor error (error code: 115) will occur, the home position
return is not executed.
(e) Home position return is started during the proximity dog ON, it is started
from the "creep speed".
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