### 6 ISA-95 Data Representation Model

### 6.3 Core Data Type DataType

## 6.3.11 CDTRate

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