is there some configertion is wrong ?
i lost the previous value of exception
the scan rate is 6s
and i think the trend should be like this is reasonable
here is my configertion and thx a lot .
It sounds like you want to set the step attribute to "on" such that visualization clients and sampled data (interpolated) queries will use "hold" the previous values. This does not appear to be related to PI Interface data exception processing, but rather how to understand data results.
Typically, I have step off for raw data and often use step on for calculated data.
thank you to help me
but what i mean is this
i wanna blue trend , but i cant got the point c ,so my trend is like red .
How does this data look in PI Vision or PI Processbook and not the preview window of PI System Explorer? I think the trending tool in PSE acts differently and just shows the values trended over time. I also might turn step on for a calculated value and/or turn compression off and either let "compression" be controlled somewhat by the scan rate of the tags feeding the calculation or by the period of the calculation if I am choosing a periodic calculation.
Thanks, I now understand your problem better. My previous answer doesn't really apply.
I'm not exactly sure why there are no values there. I do see your compression deviation is set to zero, so compression is likely not a factor. Is this from an interface that supports polling/advised tags?
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