8.2.3 Engineering units with reference to IEC 61987 CDD

The Property EngineeringUnits – inherited from AnalogUnitRangeType (see OPC 10000-8 Amendment 1) – shall be used to define the unit for the AnalogSignalVariableType instance and also for its ActualValue and SimulationValue component Variables.

In addition, each EngineeringUnits Property shall provide a HasDictionaryEntry reference to the IEC Common Data Dictionary entry for "unit of measure" which is 3:0112/2///61987#ABA968#002. Figure 15 illustrates this with an example.

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Figure 15 – EngineeringUnits Property with HasDictionaryEntry Reference