Interrupt From Modules; Precautions For Using The Annunciator (F) - Mitsubishi Electric MELSEC iQ-R-R00CPU User Manual

39.2

Interrupt from Modules

This section describes the precautions for interrupts from modules.
When the old control system is switched to the new standby system
The old control system retains the interrupt factors that have occurred even after the system is switched to the new standby
system by system switching before execution of an interrupt program. After the systems are switched again, the interrupt
program of an interrupt factor that the old control system has retained will be executed.
Since the interrupt factor that has occurred on the old control system is not inherited to the new control system, the interrupt
program of an interrupt factor that has occurred on the old control system will not be executed on the new control system.
When the old standby system is switched to the new control system
The old standby system retains the interrupt factors that have occurred. After the old standby system is switched to the new
control system by system switching, the interrupt program of an interrupt factor that the old standby system has retained will
be executed on the new control system.
When the old standby system has retained multiple interrupt factors, the scan time may greatly increase.
39.3

Precautions for Using the Annunciator (F)

This section describes the precautions for using the annunciator (F).
When the SET F instruction is used to register the annunciator
When the execution condition of the SET F instruction has been satisfied at system switching, the annunciator that is turned
on by the SET F instruction can be registered in the new control system. The SET F instruction registers the annunciator
at the rising edge of the execution condition. To register the annunciator in the new control system at system switching, add a
normally closed contact of SM1643 (ON for only one scan after system switching (standby system to control system)) as the
AND condition in the execution conditions of the SET F instruction.
Ex.
M0 (standby system)
Normally closed contact of SM1643
(standby system)
Execution condition (F10) of
the SET F instruction (standby system)
F10 (standby system)
(1) When M0 turns on in the control system before system switching, M0 of the standby system also turns on as a result of tracking transfer.
(2) The contact turns off for one scan after system switching.
(3) When the execution condition turns on, annunciator information is registered by the SET F instruction.
When the OUT F instruction is used to register the annunciator
When the execution condition of the OUT F instruction has been satisfied at system switching, annunciator information is
registered in the new control system at system switching.
39 PRECAUTIONS ON PROGRAMMING
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39.2 Interrupt from Modules
Switching systems
(1)
ON
OFF
ON
OFF
ON
OFF
ON
OFF
(2)
(3)