CP1E-E@@D@-@ CP1E-N@@D@-@/NA20D@-@
Backing Up and Restoring DM Area Data
The contents of the DM Area (D) will become unstable if the power supply is interrupted for longer than the backup time of the built-in capacitor
(50 hours for an E-type CPU Unit, 40 hours for an N/NA-type CPU Unit without a Battery).
The contents of the specified words in the DM Area data can be backed up from RAM to the built-in EEPROM backup memory during operation
by turning ON a bit in the Auxiliary Area. The number of DM Area words to back up is specified in the Number of CH of DM for backup Box in the
PLC Setup. If the Restore D0- from backup memory Check Box is selected in the PLC Setup, the backup data will automatically be restored to
RAM when the power is turned back ON so that data is not lost even if power is interrupted.
CP1E CPU Unit
A751.15 (DM Backup Save Start Bit) turned ON
Built-in RAM
DM Area (D)
Built-in EEPROM Backup Memory
DM backup data
Data backed up
Data restored
D0
Specified number of words
D(n-1)
Specify the number of words starting
from D0 in the Number of CH of DM
for backup Box in the Startup Data
Read Area in PLC Setup.
DM backup data is restored to the RAM when power supply is
turned ON again if the Restore D0- from backup memory Check
Box is selected in the Startup Data Read Area in the PLC Setup.
Conditions for Executing Backup
Specified words starting from D0 in the RAM can be saved to the built-in EEPROM backup memory by turning ON A751.15.
(These words are called the DM backup words and the data is called the DM backup data.)
A751.15 (DM Backup Save Start Bit) can be used in any operating mode (RUN, MONITOR, or PROGRAM mode).
Words That Can Be Backed Up
• E-type CP1E CPU Units: D0 to D1499
• N/NA-type CP1E CPU Units: D0 to D6999
Number of Words To Back Up
The number of words to back up starting from D0 is set in the Number of CH of DM for backup Box in the Startup Data Read Area in the PLC Setup.
Restoring DM Backup Data to RAM When Power Is Turned ON
The DM backup data can be restored to RAM when power is turned ON by selecting the Restore D0- from backup memory Check Box in the
Startup Data Read Area in the PLC Setup.
The DM backup data will be read from the backup memory even if the Clear retained memory area (HR/DM/CNT) Check Box is selected in the
PLC Setup.
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OMRON [ OMRON ELECTRONICS LLC ]
