Yaskawa MP2300S Basic Module - Manual (Page 454)

Appendix H Optional Functions
H.3 Battery Backup for Table Data
A-132
( 6 ) Precautions When Using Battery Backup for Table Data
a) When you have created table data or changed definitions using the battery backup function, always save the
data to the flash memory before turning OFF the power. Definitions for tables and column attributes are
stored in the volatile memory so data will be cleared if it is not saved to the flash memory before the power is
turned OFF.
b) Even if the table data is not saved to the flash memory before the power is turned OFF, the table data can still
be saved if battery backup memory is selected in the table data store target. Note that table data cannot be
saved if the battery is not installed or the voltage of the battery is too low. If the table data was not saved for
any of these reasons, you can return to normal operation if you initialize the table data.
c) When battery backup memory is selected in the table data store target, blocks are used as units for an area
reserved to store table data. If table data definitions are saved and deleted repeatedly, empty blocks will
remain. To avoid empty blocks, use MPE720 to save controller programs to the computer. Right-click on the
PLC folder and select Transfer - All Files - From Controller to MPE720. Then initialize the battery backup
memory and save the programs to the controller.
d) When you want to initialize the system, store the programs of the controller in a personal computer by using
MPE720 (right-click on the PLC folder and select Transfer - All Files - From Controller to MPE720). The
data in the battery backup memory will be cleared to zero if the power is turned ON after the dipswitch INIT
is set to ON.
e) If the table data store target is changed, all table data will be cleared to zero even if the data size remains the
same.