MergenHub Virtual Tags — calculated tags
A formula engine that turns raw data into meaningful quantities. Average, totalizer, cumulative delta and conditional logic — all as tags in the OPC UA tree.
What it does
Virtual Tags computes new values from existing tags. For example the totalized sum of a flow, the hourly average of a temperature, the difference of two values, or a flag produced from a condition. The result becomes a standard OPC UA tag under _AdvancedTags and is logged to the historian.
Key features
Full parity across types such as the formula engine (POLY/MAP/CLAMP/LERP, trigonometry), Totalizer, Run-gated Average/Max/Min, Derived rate/trigger, Link write-back and Oracle Cumulative; a dedicated dialog per type.
Core capabilities
Totalizer
A totalizer that accumulates a rate/flow over time (AdvancedTagType); reset and persistence.
Average / Max / Min
Run-gated average, maximum and minimum; window and trigger configuration.
Cumulative / Derived
Cumulative delta (Oracle Cumulative), derivative rate and trigger-based tags.
Expression engine
An expression editor with POLY, MAP, CLAMP, LERP, trigonometry and conditional logic.
Link write-back
Support for linking a tag to another tag and writing back (link).
_AdvancedTags OPC
Calculated tags live in the standard OPC UA tree; full compatibility with historian and SCADA.