I have a TimeSeriesChart history graph that I use as popup for all history enabled values.
My data is via OPC-UA
My problem is, when I am view-ing a history for a tag thats network connection has been lost
The chart shows current value 0 for hours since last valid read value and is very baffling.
I must use Quyery mode AsStored, because I found no other way to draw a horizontal line on the graph till next valuechange
If I check the dataset binding of it, I see that on easch check the last value is 0 with the curreent timestamp. and that is what ruins my graph.
If I set Query mode to periodic, the main problem is that between two datapoints the chart draws a sloped line and does not reflect that the value did not change between two points. especially for tags where value changes are not that often
see a detailed screen capture and ask details if necessary
UPDATE:
And another big issiue I have with this chart whatever I try. (and probably this is the reason for the problem above)
Let's imagine the following scenario
at timpestamp 13h:20m:00s I have a value of 10 and 13h:20m:12s I have a value of 5
If I choose Query mode "AsStored" the chart shows 10 from 13h:20m:00s to 13h:20m:06s and 5 from 13h:20m:06s to 13h:20m:12s
If I choose Query mode "Periodic" whatever period even 1second I choose, the chart shows a line as a downslope from 13h:20m:00s to 13h:20m:12s.
The aggregate configured at the key seems to have no difference if I set it to LastValue os MinMax or whatever valid value I set. (Invalid values result in error).
Ignition v8.1.45