Operation Of Out Instructions, Set/Rst Instructions, Or Pls/Plf Instructions Using Same Device - Mitsubishi MELSEC-Q Series Programming Manual

3.10
Operation of OUT Instructions, SET/RST
Instructions, or PLS/PLF Instructions Using Same
Device
This section explains the operation when the OUT instructions, SET/RST instructions, or PLS/
PLF instructions that use a same device are executed multiple times in one scan.
(1) OUT instructions that use a same device
Avoid executing the OUT instructions that use a same device multiple times during one
scan. If the OUT instructions that use a same device are executed multiple times during one
scan, the specified device is turned ON/OFF according to the operation result obtained by
each execution of the OUT instruction. Since the ON/OFF status of the specified device is
determined by each execution of the OUT instruction, turning ON/OFF may be repeated
during one scan.
The following figures show the operation example of the ladder that turns ON/OFF the same
internal relay (M0) by the inputs X0 and X1.
[Ladder]
[Timing chart]
X0
X1
M0
For refresh type CPU modules, the ON/OFF status of the OUT instruction executed last
during one scan is output when output (Y) is specified for the OUT instruction.

3.10 Operation of OUT Instructions, SET/RST Instructions, or PLS/PLF Instructions Using Same Device

3-40
X0
OUT
EN ENO
d
X1
OUT
EN ENO
d
END
ON
OFF
ON
OFF
ON
OFF
M0 turns ON because X0 is ON.
M0
M0
X0 OUT
EN ENO
d M0
X1
OUT
EN ENO
d
END
M0 turns OFF because X1 is OFF.
X0 OUT
EN ENO
d
X1
OUT
EN ENO
M0
END
M0 turns ON because X1 is ON.
M0 remains OFF because X0 is OFF.
M0
d M0