Omron CJ2 User Manual page 220

8 Backup Operations
Restoring Data
PLC data can be restored to a previous state by transferring backup file data to a connected PLC.
Before the data is restored, a comparison will be made automatically with the applicable PLC and the
results will be displayed.
@: Check boxes will appear for Units to which data can be
restored.
Configuration: Indicates whether the configurations match between the
backup file and the PLC.
Before the data is restored, the contents of the data can be checked by starting the Support Software
for that Unit.
Precautions for Correct Use Precautions for Correct Use
The CPU Unit will be changed to PROGRAM mode before restoring the data. This will stop oper-
ation. Be sure it is safe to stop CPU Unit operation before restoring the data.
Precautions for Safe Use
• Sufficiently check the data that is selected for restoring before performing the next step. If the
correct data is not restored, unexpected operation may occur in the controlled system after the
data is restored.
• Some Special I/O Units and CPU Bus Units operate with parameters that are stored in the
CPU Unit. If one of these Units is selected for backup, restrictions will be displayed in the Com-
ments Area of the Backup from PLC Dialog Box. Confirm the restrictions, and always select
the Special I/O Unit or CPU Bus Unit together with the CPU Unit when backing up or restoring
data. If the data from both Units is not backed up or restored together, unexpected operation
may occur in the controlled system.
• If there are any backup restrictions for the Units to which data is being restored, the restric-
tions will be displayed in the Comments Area of the Backup from PLC Dialog Box. Confirm the
restrictions, and always take the required measures. If required measures are not taken, unex-
pected operation may occur in the controlled system after the data is restored.
• Confirm that stopping PLC operation will not create any problems before restoring data during
PLC operation. If the PLC stops at an unanticipated time, unexpected operation may occur in
the controlled system.
• Always turn the power supply to the PLC OFF and then ON after restoring data. If the power
supply is not turned OFF and then ON, memory in the PLC may not be updated to the restored
data, which may cause unexpected operation of the controlled system.
• Forced status can be backed up, but it cannot be restored. If you restored data that contained
forced status, use the CX-Programmer after restoring the data to force-set or force-reset bits
as required. If required bits are not force-set or force-reset, differences in the forced status in
memory may cause unexpected operation of the controlled system.
8-6 CJ2 CPU Unit Hardware User's Manual