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6.3 Core Data Type DataType ToC Previous Next

6.3.8 CDTMeasure ToC Previous Next

The CDTMeasure is a generic term for DataTypes that conform to the Measure type. The actual DataTypes are defined separately according to each primitive data type of content component. Table 28 defines the DataTypes.

Table 28 - DataTypes according to CDTMeasure

Content Component data type OPC UA CC DataType OPC UA CDT DataType
Decimal Decimal CDTMeasureDecimal
Double Double CDTMeasureDouble
Float Float CDTMeasureFloat
Integer Int16 CDTMeasureInt16
  Int32 CDTMeasureInt32
  Int64 CDTMeasureInt64

The CDTMeasure is a numeric value determined by measuring an object along with the specified unit of measure. It “is used to represent a kind of physical dimension such as temperature, length, speed, width, weight, volume, latitude of an object. More precisely, it should be used to measure intrinsic or physical properties of an object seen as a whole according to CCTS.

Table 29 - CDTMeasure Definition

Attribute Value
BrowseName One of the OPC UA CDT DataType value in Table 28
IsAbstract False

Subtype of the one of the OPC UA CC DataTypes Table 28

References NodeClass BrowseName DataType TypeDefinition ModellingRule
HasCDTSupplemental Variable Unit EUInformation PropertyType Optional

Unit defines measurement units defined in OPC 10000-8. EUInformation identifies unit by three letters specified in Unit element. This rule is reasonable if code set of Unit is based on UNECE. Otherwise, code shall be set into Display, and Unit shall be set to (-1).

NOTE: OPC 10000-8 defines EUInformation DataType to indicate code of the unit defined in UN/ECE. This standard uses the EUInformation to represent code defined in UN/ECE instead of CDTCode.

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