Thanks, Hegamurl for the great videos! I enjoy learning about PLCs, but this one I can not figure out.
I have an S7-1200 PLC connected to a KTP 400 Basic HMI, Profinet.
As the picture shows some values in the trend get lost, show like 0 or +- infinity.
After a while, the spikes move to other places on the trend.
Why is it like so? When the trend curve is updated, is all the data for the entire curve sent to the HMI? Is it possible that some values are lost on the way? If so, why are the lost values always replaced by 0 and +- infinity?
Hello Herleik Vågslid,
are you sure value of Tag on PLC not change out of range on trend, like >70 or < -30?
I think , the problem is not in Trend. Maeby the problem is in PLC( logic to convert in temperature), or sensor.