Operation Restart After Being Stored - Mitsubishi MELSEC L Series User Manual

14.4

Operation Restart After Being Stored

When operation is restarted after the programmable controller has been stored under the following conditions, data in
the standard RAM of the CPU module may be corrupted. Before restarting operation, format the standard RAM using a
programming tool.
After that, write the backup data to the standard RAM.
• When stored without a battery installed
• When stored exceeding the guaranteed battery life
Remark
If the latch data backup (to standard ROM) function is used, latch data can be held without using a battery. For this reason,
when programmable controller operation is restarted after being stored, the data before storage can be used.
For the formatting method of the standard RAM, refer to the following.
Operating manual for the programming tool used
● Before storing a programmable controller, back up all data stored in each memory.
● A CPU module checks the status of the following data when the module is powered on or reset. When the module detects
an error, data will be initialized.
• Data in the standard RAM
• Error history
• Latch data (latch relay, devices in latch setting range set in the parameter, special relay (SM900 to SM999), and
special register (SD900 to SD999))
• Sampling trace data
CHAPTER 14 MAINTENANCE AND INSPECTION
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