Mitsubishi Q series Programming Manual page 95

4 SFC PROGRAM CONFIGURATION
POINTS
The operation of SM325 differs depending on the CPU module.
• For the Basic model QCPU, High Performance model QCPU, Process CPU, and
QnACPU
The SM325 turns ON/OFF at STOP RUN of the CPU module according to the output
mode setting at block stop of parameters.
•
For the Universal model QCPU
The system turns ON/OFF according to the output mode setting at block stop of
parameters when turning ON power supply of the PLC and resetting the CPU module.
Output Mode Setting at Parameter Block STOP
Turns OFF (coil output OFF)
Remain ON (coil output held)
However, by turning ON/OFF SM325 in the user program, the output mode at block STOP can
be changed independently of the parameter setting.
(c) The STOP/RESTART bit switches ON when the SFC control "block STOP" instruction
(PAUSE BLm) is executed.
(2) Block RESTART instruction (RSTART)
(a) The block in question is restarted from the step where a STOP occurred.
An "operation HOLD status" step (with transition check or without transition check) which
has been stopped will be restarted with the operation HOLD status in effect.
A "coil output HOLD" step cannot be restarted after being stopped as it becomes
deactivated at that time.
(b) Depending on the ON/OFF status of the "block STOP-time operation output flag (SM325)",
the operations of the PLS instruction and
change.
• When SM325 is ON (coil output held)..........................Not executed
• When SM325 is OFF (coil output OFF) .......................Executed again
(c) When the block STOP/RESTART bit of the SFC information devices has been set, the
block STOP/RESTART bit also turns OFF.
[Operation Error]
• Error No. 4621 occurs when the specified block does not exist or when the SFC program is
in the stand-by status.
[Program Examples]
(1) Block 1 is stopped when X1 switches ON, and is restarted when X2 switches ON.
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P instruction after block STOP cancellation
aX1 aX2
PAUSE BL1 PSTART BL1
SM325
OFF
ON
MELSEC-Q
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