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Cautions on Changing Setting Parameters 
 
 
The setting data of the T300MVi MV is saved in an EEPROM, non-volatile memory.  When the 
micro controller initializes at power-up, it reads the EEPROM data and copies it to the RAM (Random 
Access Memory).  From then on, the micro controller controls the drive using the values in the RAM. 
 
When the setting parameters are changed, by the display-keypad or personal computer ("support 
tool"), only the execution parameters in RAM are changed.  If they need to be stored, they must be manually 
written to the EEPROM.  Without this operation, the next initialization or power up will cause them to be 
replaced by the old data. 
 
When a write to the EEPROM is performed, write processing may take 30 seconds.  Turning off the 
control power supply during write processing will make both the RAM and EEPROM data abnormal.  When 
the power is turned on again, this abnormal data will result in an error ("CHECK ERROR") preventing the 
drive from running.  If such an error occurs, the settings must be reloaded from a saved file.  If no setting file 
exists, the drive must be re-commissioned. 
 
Do not turn off the control power supply under any circumstances while 
writing data to the EEPROM. 
CAUTION