Can't Modify the PLC Program

Hello Everyone,

                         Last time I have worked with CPU 314 IFM PLC. One Program was already there in the PLC. I modified some logics in that program but once I switched off PLC the modifications wasn't there in the PLC. Hence the previous program which was already in the PLC memory is there. Only modified parts wasn't there. What may be the reason for this?...I am having doubt with the battery..

Hello,

Did you use the function: Save Ram to Rom?

So the program is stored on internal Eprom.

Best regards,

Wizard