Mitsubishi Q Series Programming Guide

6 - 9 6 - 9
6 SFC PROGRAM EXECUTION
MELSEC-Q
6.3.2 Restarting a stopped block
The methods for restarting a block which has been temporarily stopped during SFC program
processing are described below.
(1) Restarting block processing
The methods for restarting a block which has been temporarily stopped are shown below.
Restart Method Operation Description Remarks
Restart by SFC
control instruction
• Processing of the specified block is restarted by
an SFC control instruction at a step (operation
output) or sequence program outside the
stopped block.
Condition
RSTART BLm
m is the block No.
• Convenient for returning to automatic operation
when the manual control END signal is output
at the temporary STOP.
RESTART by SFC
information device
• The execution of the corresponding block is
restarted by forcibly turning OFF the "block
STOP/RESTART bit", which was set to each
block as the SFC information device, in the
program or peripheral device.
• Convenient for confirming operation by step
control at debugging and test operations,
because block processing can be restarted
from a peripheral device without requiring a
program.
(2) Active step when restart occurs
The step which is active when a block is restarted varies according to the status which existed
when the STOP occurred, as shown below.
Operation Output at Block RESTART
Held step
Output Mode Setting at
Block STOP
Active step other than
held step
(including HOLD step
whose transition
condition is not
satisfied)
Coil HOLD step (SC)
Operation HOLD step
(without transition
check) (SE)
Operation HOLD step
(with transition check)
(ST)
At coil output OFF
• Restart disabled.
(Since the step is
deactivated at a block
STOP)
At coil output HOLD
• Returns to normal
operation.
• Restarts as held.
• Restarts the execution
of the operation output
in a HOLD status.
• Restarts the operation
output in a HOLD
status.
• Also checks the
transition condition.
: 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.

Mitsubishi Q Series Specifications

General

Brand	Mitsubishi
Model	Q Series
Category	Control Unit
Language	English