Mitsubishi Electric MELSEC FX3U Programming Manual page 954

FX /FX /FX Series Programmable Controllers
3G 3U 3UC
Programming Manual - Basic & Applied Instruction Edition
Item
Circuit blooks which require attention
on operation after writing during RUN
Other
952
When writing to a circuit block during RUN, which includes the following instructions, the
following results.
• instruction for falling edge pulse
When writing is completed during RUN for a circuit including an instruction for falling
edge pulse (LDF, ANDF, or ORF instruction), the instruction for falling edge pulse is not
executed without regard to the ON/OFF status of the target device of the instruction for
falling edge pulse.
When writing is completed during RUN for a circuit including an instruction for falling
edge pulse (PLF instruction), the instruction for falling edge pulse is not executed without
regard to the ON/OFF status of the operation condition device.
It is necessary to set to ON the target device or operation condition device once and then
set it to OFF to execute the instruction for falling edge pulse.
• Instruction for rising edge pulse
When writing is completed during RUN for a circuit including an instruction for rising edge
pulse, the instruction for rising edge pulse is executed if a target device of the instruction
for rising edge pulse or the operation condition device is ON.
Target instructions for rising edge pulse: LDP, ANDP, ORP, and pulse operation type
applied instructions (such as MOVP)
While write during RUN is
executed
OFF
ON
*1. The PLS instruction is not executed.
When writing to a circuit block during RUN, which includes the following instructions, the
following results.
• Pulse instruction during rising edge of operation results (MEP instruction)
After writing to the circuit with MEP instructions during RUN, the MEP instruction result
turns ON (conductive) while the operation results leading up to the MEP instruction are
ON.
• Pulse instruction during falling edge of operation results (MEF instruction)
After writing to the circuit with MEF instructions during RUN, the MEF instruction result
turns OFF (non-conductive), regardless of the operation results up to the MEF
instruction.
The operation results of the MEF instruction turns ON (conductive) when the operation
results leading up to the MEF instruction are turned OFF.
Operation results leading up to MEP/MEF
instruction
OFF
ON
• When GX Developer Ver. 8.13P or later is used in FX
RUN, the following will occur.
If the number of program steps is reduced by deleting contact or coil application
instructions, etc., the program becomes shorter by the number of reduced steps.
• When GX Developer Ver. 8.72A or later is used in FX
the following will occur.
If the number of program steps is reduced by deleting contact or coil application
instructions, etc., the program becomes shorter by the number of reduced steps.
A Programming Tool Applicability and Version Upgrade History
A-1 Programming Tool Applicability
Caution
Instruction for
rising edge
pulse
Not executed
*1
Executed
MEP instruction
(non-conductive)
(conductive)
3U
3G
Instruction for
falling edge
pulse
Not executed
Not executed
MEF instruction
OFF OFF
(non-conductive)
ON OFF
(non-conductive)
/FX PLCs to write data during
3UC
PLCs to write data during RUN,