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6.3.11 CDTRate ToC Previous Next

The CDTRate is a generic term for DataTypes that conform to the Rate type. The actual DataTypes are defined separately according to each primitive data type of content component. Table 32 defines the DataTypes.

Table 32 - DataTypes according to CDTRate

Content Component data type OPC UA CC DataType OPC UA CDT DataType
Decimal Decimal CDTRateDecimal
Double Double CDTRateDouble
Float Float CDTRateFloat
Integer Integer CDTRateInt32

The CDTRate is a quantity, amount, frequency, or dimensionless factor, measured against an independent base unit, expressed as a quotient. In addition CCTS describe it is used to represent the numerical quotient resulting from a comparison of two independent things such as a quantity measured with respect to another measured quantity such as a rate of speed, a measure of a part with respect to a whole - a proportion such as the mortality rate, a tax rate, the cost per unit of a commodity or service or a charge or payment calculated in relation to a particular sum or quantity such as interest rates. The quotient is calculated by taking into account the Rate.Multiplier.Value and Rate.Base.Multiplier. Value supplementary components that affect the unit codes used at the numerator and the denominator.

Table 33 - CDTRate Definition

Attribute Value
BrowseName  One of the OPC UA CDT DataType values in Table 32)
IsAbstract False

Subtype of the CC DataType according to the BrowseName**

References NodeClass BrowseName DataType TypeDefinition ModellingRule
HasCDTSupplemental Variable Multiplier Double PropertyType Optional
HasCDTSupplemental Variable Unit EUInformation PropertyType Optional
HasCDTSupplemental Variable Currency CurrencyCode PropertyType Optional
HasCDTSupplemental Variable BaseMultiplier Double PropertyType Optional
HasCDTSupplemental Variable BaseUnit EUInformation PropertyType Optional
HasCDTSupplemental Variable BaseCurrency CurrencyCode PropertyType Optional

Multiplier defines multiplier of the numerator. The default value is “1” if the element is omitted.

Unit defines the unit of measure of the numerator. The Unit is represented in EUInformation defined in OPC UA Part8.

Currency defines the currency unit of the numerator.

BaseMultiplier defines multiplier of the denominator. The default value is “1” if the element is omitted.

BaseCurrency defines the currency unit of the denominatorBaseUnit defines the unit of measure of the denominator. The BaseUnit is represented in EUInformation defined in OPC UA Part8.

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