Problems with step 7

Hi,
I use the CPU 417-4H from Siemens with the Wincc interface. To the system are connected analog inputs SM 331 that are not connected to anything (just a resistor). Even that they are connected only to a resistor and they are in a closed cabinet with no vibration they are giving from time to time a wire break message. The wire break is not consistent with anything and is coming randomly just for about 20 msec each time. Did any buddy have this kind of problem? Does anyone knows how to solve it?

I had similar issues, I ended up just not using the diagnostics for wirebreak (setup in hardware config) and creating my own wirebreak alarms by comparing the actual value to my determined wirebreak value.

The nice thing about this is that if you have one that flickers you can always suppress it with a timer

Hi,
thank you for your answer. We can't stop using the diagnostics. Did Siemens helped you with this problem? Do you know exactly why it happened?