retain date and Time in Siemens Step 7

[mikey431 3]

I have a program coded in Siemens S7 and the PLC is CPU-314. Customer complains the date and time kept reset to 2004 after power down and i am not sure how to fix this. Anybody has any idea ?

[Renato 0]

Hello mickey431 You can use SFC0 "SET_CLK", available on Ladder editor Program elements "Libraries/stdlibs/builtin". If you see help about this SFC, there is an example about how to set date and time on the CPU. So you can move the current date/time to a DB (always unless on warm restart cycle) and on warm restart (OB100) you can set date/time on the CPU. Regards Renato.