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#004. Figure 15 illustrates this with an example.

Figure 15 - EngineeringUnits Property with HasDictionaryEntry Reference