I'm at a site with S5 115U 944 CPU containing EPROM (not EEPROM!) with old program, i dont have an UV Eraser, so now I intend to transfer the new program into the PLC memory directly. With the battery installed (hence retaining the PLC RAM contents in the event of power cycle), what can be the consequences if the old program is still stored on EPROM and new program is running in the PLC memory?
I know, that in the case of total power loss, on restart the PLC memory will be overwritten with the old program still residing on EPROM. But can they run aside (two different programs) if every thing is normal? My question is that.