help about s5-135u siemens

[hydarpour]

hello miss/mr

We have a control system that works with plc S5-135U.

two cpu (p/n:6ES5 921 & 922)of plc have ram card.

The problme is here:When cpu manualy have gone to stop (without intrupt power supply and with good battery back up)and cant run again cpu until download again programs.

 

[Marshy]

Not sure I get your problem. Are you saying you manually switched one of the CPU's to stop and then it wouldn't go back to run until you re downloaded the program?
If the CPU went to stop without you manaully switching it stop you need to examine the contents of the I-stack to find out why.

I've worked with 135Us before with 2 CPU's in the rack. If I remember rightly to do a complete restart of the system you need to:
Switch both CPU's and the Co-Ordinator module to stop.
Do a cold-restart on CPU1 then switch back to stop.
Do a cold-restart on CPU2 then back to stop.
Put both CPU's in to run
and finally then the co-ordinator into run (or test)

Hope this helps......

 

[ojz0r]

I agree with Marshy; you need to check the i-stack and figure out what is wrong.
The CPU probably preforms an illegal operation or writes an illegal value and that would be why you have to download the program again becours the program doesnt contain the error.

So try finding the connection between where the machine goes wrong and the PLC shuts down using the i-stack.