I’m having some trouble displaying the Current Value of a tag on the Power Charts Pen Control Panel. However, when I select other values (i.e. Minimum (see first image), Maximum, or Average) those appear in the Pen Control Panel. Has anyone else come across this issue or how to fix it?
I found that when selecting a historical period that extends beyond the current time, then the Current Value drops out of the pen control panel, i guess because the current value is derived from the end time of the chart and no data is availble yet as the historical range selected ends in the future.
Hope that helps.
Simon
Hey Simon, thank you for the response. Unfortunately that does not work, see the image below.
It does however work when I change from Historical to Realtime, see below.
Then I suspect Current Value is undefined in when using a Historical view. Populating this value would be inherrently simpler in a Real time view as the current value could always be sampled from the last value in the dataset, without a separate read of each tag’s value from the gateway. To do this with the a Historical view the PowerChart would have to find the current time and data in returned dataset. One would think that the current value would be available directly from the gateway tag provider, however, the PowerChart object may not have permission to reach out for this from the gateway, it may be limited to the dataset that it is provided with to determine and populate any displayed fields.
This is all conjecture of a layman though, I don’t know the inner workings of the PowerChart. perhaps a more experienced member can chime in and clear things up.
If you really want to need to use a Historical view and show the current value then you could create a view with a flex (row) container beneath the PowerChart, you could then put regular tag value displays in the container with the tag paths derived from tags used in the PowerChart. This is a somewhat crude solution, given the PowerChart object formats data panel nicely for you. Can you not use a Realtime view and (if need be) use a datetime picker to define the start and subtract this from now() to determine the range (time length) of the Realtime display?
End ramble