Block Stop/Restart Bit - Mitsubishi Electric MELSEC-Q Series Programming Manual

Block STOP/RESTART bit

The block STOP/RESTART bit is used to temporarily stop processing while the corresponding block is active.
• When the designated block STOP/RESTART bit is switched ON by the sequence program or peripheral device, processing
will be stopped at the current step of the block in question. If a START status is in effect at another block, the STOP will still
occur, but the START destination block will remain active and processing will continue. To stop the START destination block
at the same time, the START destination's block STOP/RESTART bit must also be switched OFF.
• When a block is stopped by switching the block STOP/RESTART bit ON, the STOP timing will be as shown below.
Setting of Operation
Output Mode Output at
at Block Stop Block Stop
in PLC (SM325)
Parameter
Turns OFF OFF
(coil output OFF) (coil output OFF)
Remains ON
(coil output held)
Remains ON ON
(coil output held) (coil output held)
*1 The held step indicates the step whose attribute has been set to the HOLD step (SC, SE, ST) and which is being held with the transition
condition satisfied.
The operation of SM325 differs depending on the CPU module.
• For the Basic model QCPU, High Performance model QCPU, and Process CPU
SM325 turns ON/OFF according to the parameter setting (output mode setting at block stop) at STOPRUN
of the CPU module.
• For the Universal model QCPU and LCPU
SM325 turns ON/OFF according to the parameter setting (output mode setting at block stop) when the CPU
module is powered ON or is reset.
Turning OFF the parameter (coil output OFF): SM325 is OFF.
Remaining ON the parameter (coil output held): SM325 is ON.
Note that the output mode at block stop can be changed regardless of the parameter setting by turning ON/
OFF SM325 in the user program.
4 SFC PROGRAM CONFIGURATION
110
4.5 SFC Information Devices
Status of Operation
STOP-time
Active step other than held
Mode Bit
step (including HOLD step
whose transition condition is
not satisfied)
OFF or no • Immediately after a STOP request
setting is made, the coil output of the
(immediate operation output is turned OFF and
stop) the block is stopped.
• The status remains active.
ON • Normal operation is performed until
(STOP after the transition condition is satisfied.
transition) • When the transition condition is
satisfied, the end processing of the
corresponding step is performed.
At the same time, the transition
destination step becomes active
and the block stops immediately.
OFF or no • Immediately after a STOP request
setting is made, the block is stopped with
(immediate the coil output of the operation
stop) output being held.
• The status remains active.
ON • Normal operation is performed until
(STOP after the transition condition is satisfied.
transition) • When the transition condition is
satisfied, the end processing of the
corresponding step is performed.
At the same time, the transition
destination step becomes active
and the block stops immediately.
*1
Held step
Coil HOLD Operation HOLD
step (SC) step (without
transition
check) (SE)
• Immediately • Immediately after a STOP request is
after a STOP made, the coil output of the operation
request is output is turned OFF and the block is
made, the coil stopped.
output of the • The status remains active.
operation
output is
turned OFF
and the block
is stopped.
• The status
becomes
inactive.
• Immediately after a STOP request is made, the block is
stopped with the coil output of the operation output being
held.
• The status remains active.
Operation
HOLD step
(with transition
check) (ST)