Problem using SmartClient excel add-on for data interpolation
We've been using SmartClient excel add-on to extract data from our control system.
The log configuration is set to provide 1 second samples, but this is not consistent if the actual variable value does not change (i.e., if a shutdown brings a value to zero over several samples, only the last sample of zero is provided - see figure SmartClient_prob_14). For comparison of several tag values we use the SmartClient excel interface to interpolate these values to get consistent one seconds samples.
This usually works fine if the logged variable is "live" (i.e., changing value between samples). Recently we observed that if a variable remains zero for a long period of time, none of the interpolations schemes in the excel add-on handles this well. One would expect a column with timestamps and correspondingly a column of zeros, but the result is nothing similar.
Depending on the interpolation scheme we either get a slowly increasing variable value over time (sort of integrating) or we get blank cells in that particular column. Blanks cells would not be a problem if they only were related to zero values, but that is not the case - additionally the blanks occur where we know that the variable values are not zero. These cases are depicted in figures SmartClient_prob_11 and SmartClient_prob_12, respectively.
There are 113 variables extracted for 12 hours of second samples for each file - thus to serach for patterns which may indicate zero actual variable value manually is off the table.
Anyone who has experienced something similar, and may have found a solution to this?
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Ok I see... so if the log at 800xA is showing you the desired values, we should point to Smart Client Report. I am not very familiar with it but I have look into the manual and it says that there is an option to configure the log retrieval.
"Log drop properties" option a windows pops up athen there is "log retrieval" option, then you can customize using "custom" button see details in the attached file.
Have you tried configure this parameters according what you need??
I hope this helps.
I think maybe your problem it's related to the log configuration instead of an report problem.
The log configuration allows you to configure it according different cases.
If you don´t have any changes on the value that you are logging, you can have the following scenarios according the log configuration:
1.- The log will log the data only if has detected a change in the value during the sample period.
2.- The log will log the data no matter if the value changes or not but it will do so only after a certain period of time that you configure.
3.- The log will log the data no matter if the value changes or not.
I guess your log it's configured based on option 1.
If you need that the samples are taked no matther what, option 3 would be the way, however this use more space.
If it is fine to your analysis, you could use a time limit, this means that if the value does not change in a certain period of time, the sample will be taked anyway. Let's say your sample it's every 1 second but if happen to be the same for 5 seconds in a row take a sample anyway after that time... your log would be something like this..
I hope this helps,
Hi Valeria, and thanks for replying!
I'm forced to reply this way to be able to attach files.
You're completely correct on the log configuration part.
However, the problem persist only to SmartClinet.
The control system does this interploation well by itself - see fig. SmartClient_prob_13.
As for SmartClient, the interpolation at 0 true value is nowhere near - see figure SmartClient_prob_112 (The figures depict the same tag for the same time).
When the value change, everthing is back to normal (marked by black arrow).
For short times when the true value is 0, this is not a problem since the interpolated value increases so slow. But in this case the real value has been 0 for several weeks, thus allowing the interpolation to increase to a large (but unreal) value.
Any idea of a solution to this?