Mitsubishi Electric MELSEC Q Series Programming Manual page 393

6 POSITIONING CONTROL
Do not execute the positioning control in home position return request signal (M2409+20n) ON
for the axis which uses in the positioning control.
Failure to observe this could lead to an accident such as a collision.
(5) Operation setting for incompletion of home position return
(a) Operation in selecting "1: Not execute servo program"
1) Servo program cannot be executed if the home position return request
signal (M2409+20n) is ON. However, the servo program can be
executed even if the home position return request signal (M2409+20n) is
ON in the case of only servo program of home position return instruction
(ZERO).
2) At the time of servo program start, when "1: Not execute servo program"
is selected in the operation setting for incompletion of home position
return and the axis which the home position return request signal
(M2409+20n) is ON exists also with one axis, a minor error (error code:
121) occurs and the servo program does not start.
3) JOG operation and manual pulse generator operation can be executed
regardless of the home position return request signal (M2409+20n)
ON/OFF.
4) Same operation is executed regardless of absolute position system or
not. When "1: Not execute servo program" is selected in the case of not
absolute position system, the home position return request signal
(M2409+20n) turns ON at power supply ON or reset of Multiple CPU
system and power supply ON of servo amplifier. Therefore, it must be
executed home position return before a servo program start.
5) Same operation is executed in also TEST mode.
6) This setting is valid in the real mode only. Servo program can be
executed for a virtual axis connected to the output axis which the home
position return request signal (M2409+20n) is ON.
(b) Operation in selecting "0: Execute servo program"
1) Servo program can be executed even if the home position return request
signal (M2409+20n) is ON.
CAUTION
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