Mitsubishi Electric MELSEC iQ-R Series Programming Manual page 65

If PLF instructions of the same device are used
The PLF instruction turns on the specified device when the execution command specifies an off-to-on change. The specified
device is turned off unless the execution command specifies an on-to-off change (i.e. off to off, off to on, on to on).
Thus, if two or more PLS instructions of the same device are issued during one scan, the specified device is turned on when
the execution command of each PLS instruction specifies an on-to-off change. The specified device is turned off unless the
execution command specifies an on-to-off change.
Thus, if two or more PLF instructions are issued during one scan, the device turned on by a PLF instruction may not turn on
for one scan.
X0
PLF
X1
PLF
• If X0 and X1 differs in the on/off timing (i.e. the specified device does not turn on for one scan)
END
ON
OFF
X0
X1
OFF
ON
OFF
M0
(1) Since X0 turns off, M0 turns on.
(2) Since X1 is other than turning off, M0 turns off.
(3) Since X0 is other than turning off, M0 remains off.
(4) Since X1 is other than turning off, M0 remains off.
M0
M0
X0
PLF M0
X1
PLF M0
END
ON
OFF
(2)
(1)
X0
PLF M0
X1
PLF M0
END
(4)
(3)
1.5 Precautions on Programming
1
1 OVERVIEW
63