Need to display an hour average of a value on screen next to the real-time value.
The Animations for Historic Data option in the manual sounds just like what I need but when I put the tag in the expression as described, the expression shows the Invalid Tag(s) message and the text object shows ***Error***.
The tag has Historic enabled and the on screen menu Display Historic Trend option works and show a trend with historical data.
I’m trying this for the value animation expression and get the error:
"..Tags DNP.Level.Historic.ProcessedValue ('D-1D', 'D', 3)"
If I use this I get the current value:
Is the <point path and name> something else?
Animations for Historic Data
You can add animated historic values to a Mimic. This is useful when you want a Mimic to show calculated values, such as the daily average value of a point.
To use historic data in an expression, you need to include the Historic properties of a point. For example, you could animate a text box to show the daily average of a point by using the following expression to animate the Value property:
"<point path and name>.Historic.ProcessedValue ('D-1D', 'D', 3)"
I also tried the OPC Historic Tag option on the expression and there are no errors but no value is displayed on the screen.
a) The point does not have historic data enabled
b) The point name is incorrect - perhaps the relative path to the point is not right?
It looks like it had something to do with the overrides. It seems like sometimes I have to restart ViewX for them to work and also I guess these only update when the value changes. So when I display the screen they would just be blank until I made a change to the value. And this is just the OPC historic tag option I'm not sure how to get the historic data option to work. I assume they both work the same in that they don't update until the value changes. Is there another option that would update on its own? Or at least not be blank until the tag is looking at changes?
The manual has this example but I can't get it to process the calculation tag.
You have an analog point called Flow with historic data enabled.
You have an analog calculation point called Average Flow Today in the same group as the analog point Flow.
The calculation point has a trigger condition of Periodic. The period Interval is 1H, the Offset is D and the time zone is UTC. The calculation point has the expression: ".Flow;Average;D;1D".
The calculation point calculates today's average flow from the historic data collected by ClearSCADA from the analog point Flow. The expression uses a historic tag.
The calculation point updates the average flow every hour throughout the day.
I set mine to a 1M interval and a 1H offset but on the status information popup page for the tag it shows the process count as 0 and no value is displayed.
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