Hello,
I am using online chart HDA chart but I am not able to see values in the chart.
I see time values that goes on, Y values I see the scale that adapted itself but I would expect to see Y values that goes on on the chart (and I don’t see them).
I have values samped by opcua timer 7 (1000 ms) and I the task class of variables is every 1000 ms.
Any suggestion?
I suspect it is a matter of timing but I don’t know.
Thanks
OnlineChart HDA uses OPC UA Historical Data Access to retrieve the values so you need to have that configured on the PLC.
Automation Help: OPC UA C/S historical data configuration
You can also check with UA Expert by adding a new History Trend View (Document → Add → Historical Trend View) and drag the variables to the configuration part to see if the data historization is working.
Here it is also important that the client and server have their times set correctly, might be that the OnlineChart HDA is requesting data for a wrong time frame if the clocks differ.
Hi Giovanni,
Based on the behavior described, it looks like the chart is receiving the time axis updates but not displaying any Y-axis data. This is typically caused by either historizing not being active on the variable, as Tommi mentioned previously or a graph binding/configuration issue,
A few key items to verify:
Enable = true) for the exact variable used by the chart in OpcUaMap.uad, along with a valid buffer size and sampling interval.yAxisReference matches the name of a configured Y-axis.value binding points to the same variable that has historizing enabled and that the value is updating online.timeSpan settings are appropriate for the actual data range.Could you confirm whether historizing is enabled for the variable in OpcUaMap.uad and what the current yAxisReference is set to for the graph?
Best,
Rosh