Mitsubishi Electric MELSEC iQ-R Series User Manual page 335

Operation of when the data logging function is used
If data is backed up during execution of the data logging function and the function has been set to be started automatically
when the operating status of the CPU module is changed to RUN, the data logging function will be automatically executed
when the status of the CPU module changes to RUN after the restoration processing. To restart the data logging function after
the restoration processing without the above setting, use the CPU module logging configuration tool.
Restoration of when the data allocation in the program file is different
The data allocation in the program file differs depending on the firmware version of the CPU module. ( Page 140 Data
allocation and procedure of read/write operations)
When the data backed up using the CPU module with the conventional data allocation is restored to the CPU module with the
new data allocation, the restoration processing is completed successfully. In this case, data allocation in the CPU module is
different. Therefore, an error occurs when the CPU module is powered off and on or is reset, or the module operating status is
changed from STOP to RUN after the restoration processing. When the data backed up using the CPU module with the new
data allocation is restored to the CPU module with the conventional data allocation, the restoration processing may be
completed with an error.
In this case, an error occurs when the CPU module is powered off and on or is reset, or the module operating status is
changed from STOP to RUN after the restoration processing.
In redundant mode
This section describes the precautions for restoration.
■Target backup data
Restore the backup data in the CPU module of each system in the same redundant system as at backup processing. If the
backup data is restored in a system different from at backup processing, an error may be detected using system consistency
check.
■When restoring automatically by the procedure to start up each system separately
Set "Other system Start-up Timeout Setting" of "CPU Parameter" to "Not Set". When setting to "Set", an error may be
detected during restoration of the CPU module of the other system.
■When starting up the CPU module by automatic restoration
When starting up the CPU module by automatic restoration in a redundant system with redundant extension base unit, it is
recommended to use the automatic recovery function of the CPU module of the standby system.
In the following operations performed by automatic restoration, the CPU module of the system that was started up first cannot
perform tracking communications during initialization. Therefore, a stop error may occur in the CPU module of the system that
was started up later.
• The CPU modules of both systems are started up simultaneously, but the start-up timing of one system is delayed due to
the time taken for restoration.
• In the procedure for starting up systems one by one, one system is started up while the other system has been started up.
In this case, if the automatic recovery function of the CPU module of the standby system is used, the system can be
recovered by automatically restarting the CPU module with a stop error. If the automatic recovery function of the CPU module
of the standby system is not used, the CPU module with a stop error must be restarted by manual operation.
22 CPU MODULE DATA BACKUP/RESTORATION FUNCTION
333
22.2 Restoration Function
22