The VariableType defines the general characteristics of a MeasuredItem. A MeasuredItem is an OPC UA variable that represents a measured value. It adds some properties that describe the measurement parameters. It is formally defined in Table 137 and is leaned to the AnalogItemType from OPC 10000-8.

image084.png

Figure 68 – Overview MeasuredItemType

Table 137 – MeasuredItemType Definition

Attribute

Value

BrowseName

MeasuredItemType

IsAbstract

False

ValueRank

-2

DataType

BaseDataType

References

NodeClass

BrowseName

DataType

TypeDefinition

ModellingRule

Subtype of the DataItemType

0:HasProperty

Variable

0:EngineeringUnits

0:EUInformation

0:PropertyType

Mandatory

0:HasProperty

Variable

0:EURange

0:Range

0:PropertyType

Mandatory

0:HasProperty

Variable

0:InstrumentRange

0:Range

0:PropertyType

Optional

EngineeringUnits specifies the units for the DataItem’s value (e.g. DEGC, hertz, seconds). The 0:EUInformation type is specified in OPC 10000-8. If the DataType is a WeightItemType or a PrintableWeightItemType it is the unit of net, gross and tare.

EURange is specified like the EURange of the AnalogItemType in OPC 10000-8. If the DataType is a WeightItemType or a PrintableWeightItemType it is the Range of net, gross and tare.

InstrumentRange is specified like the EURange of the AnalogItemType in OPC 10000-8.