Mitsubishi Electric MELSEC iQ-R Series User Manual page 333

Time required for completing the restoration processing
The restoration processing takes more time depending on the number of backup data sets (folders), file size, and the number
of files in the SD memory card.
In a multiple CPU system, if the automatic restoration has taken time and an error has occurred in another CPU module,
another error may occur in the CPU module to which the automatic restoration was executed after the completion of the
restoration.
In that case, shorten the time for restoration. Change the setting of SD954 (Restoration target data setting) to only the device
data that is to be cleared at a system start-up, and execute the automatic restoration again.
Monitoring stop at restoration
Stop monitoring before executing the restoration processing.
When the restoration processing is executed, programs, parameters, and device/label values may not be properly monitored
because they are changing.
Reflecting restored data
Some of the parameters are reflected only when the CPU module is powered off and on or is reset. If the restoration
processing is executed while the CPU module is in the STOP state and then is switched to the RUN state, the CPU module
may not operate with the backup data. In that case, power off and on or reset the CPU module. For device/label data, since
device/label data except for latch-specified devices/labels is initialized when the CPU module is powered off and on or is
reset, restore the device/label data again as required.
Abnormal completion of restoration
Since the restoration processing will be completed with an error, do not execute the restoration processing in the following
cases.
• The name of a file in the restoration destination CPU module and the name of a file in backup data are identical, and a file
password has been set.
• Data in a backup folder has been deleted. (Do not delete the data in backup folders that are likely to be used for
restoration.)
• Backup data has problems. (Backup data has been changed or the CPU module was powered off during execution of the
backup processing.)
When the special relay and special register are restored
When a restoration is operated with the setting to restore the special relay and special register, the system will be operated
with the values (time, day of the week, day, time, and the upper limit value of the number of backup data for the automatic
backup set to the backup function setting) before restoration. (The backup function setting will not be re-set although the
special register areas are overwritten by the restoration.)
To operate the system with the restored backup function setting, set the backup function setting again.
Data protected by security functions
■File password function
Unlock the file passwords of the files in the backup target CPU module. If any files to which file passwords have been set exist
in the CPU module, the files are not restored.
■Security key authentication function
Locked programs can be restored regardless of whether security keys have been written or not. However, when the security
key has not been written to the CPU module after the restoration processing, the program cannot be executed. Restore
unlocked backup data or set the same security key.
22 CPU MODULE DATA BACKUP/RESTORATION FUNCTION
331
22.2 Restoration Function
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