HDA point names may now contain additional specifications for Percent Good/Bad and other aggregate configuration properties. This allows greater control over the data returned by Hyper Historian to OPC HDA clients.
Note, the behavior of these settings is as defined by the OPC UA specifications (Part 13: Aggregates).
This is an example tag that includes aggregate parameters:
@ICONICS.HyperHistorian.1\hh:\Configuration\Signals:RandomFast(PctGood=20;PctBad=100;).History
These keywords are all optional. (For instance, you can specify PctGood without PctBad.) All available keywords are:
• PctGood - Percent Good (integer, 0-100, default 100)
• PctBad - Percent Bad (integer, 0-100, default 0)
• UncAsBad - Treat Uncertain as Bad (Boolean, true or false, default false)
• SlopedExt - Sloped Extrapolation (Boolean, true or false, default false)
Version 10.95.4 added new expression functions: nextevent, resetevent and isevent.
These new functions are designed to allow periodic processing based on some other event (a value change, etc.). Previously, the user would have to create very fast time-based functions and use logic in the calculation itself to see if the process needed to be completed.
Here is an example use case scenario. We have a Boolean value named Start, which determines whether a product line is making product. When it is in production, we need to make periodic calculations to monitor the production line. We also need to know when the line started and stopped production.
First, create a calculation trigger as a data trigger. Select “Trigger On” as “Expression”. Then, use the following expression:
IF {{data:Calc.Start}} THEN nextevent(5000, (IF !isevent() THEN 1 ELSE 2)) ELSE resetevent(3)
Second, create a performance calculation and add the created trigger to the list of triggers in the “Triggers” section. This performance calculation will run based on created trigger events and the trigger value will contain one of the following values:
1) Production line started
2) Periodic check when production line is in production
3) Production line stopped
The trigger value can then be used in your performance calculation tag's logic.
See Also: