13 Standardized Properties and Mapping to the Properties
13.1 InstrumentRange

InstrumentRange is defined in OPC 10000-8 as Property of the AnalogItemType. In this specification the Property is used for Variables, independent of the VariableType.

The Property uses the DataType Range defined in OPC 10000-8 having a low and a high value. The mapping of an IODD ValueRange to the OPC UA Range is defined in Table 69.

Table 69 – Mapping of IODD ValueRange to OPC UA Range

IODD attribute

OPC UA field

lowerValue

low

upperValue

high

13.2 InstrumentRanges

The InstrumentRanges Property is defined by this specification and used for Variables, independent of the VariableType. The BrowseName is “InstrumentRanges” and the DataType an array of Range (defined in OPC 10000-8).

The mapping of IODD ValueRange to Range is defined in 13.1

13.3 EnumValues

EnumValues is defined in OPC 10000-8 as Property of the MultiStateValueDiscreteType. In this specification the Property is used for Variables, independent of the VariableType.

The Property uses an array the EnumValueType. When an IODD defined SingleValue is mapped to an entry of the array, the following rules apply:

The IODD value is mapped to the OPC UA value.

The IODD name is mapped to the OPC UA displayName. The IODD value contains a TextRefT referencing a text, potentially in several languages. The displayName is LocalizedText, thus also different locales can be provided. The localeId shall contain the corresponding language, and the text the referenced text.

The OPC UA description shall be left empty.

13.4 TrueState and FalseState

The TrueState and FalseState are defined in OPC 10000-8 as Properties of the TwoStateDiscreteType.

Each Property uses a LocalizedText. When an IODD defined SingleValue is mapped to such a LocalizedText, the name of the SingleValue containing a TextRefT referencing a text, potentially in several languages. The localeId shall contain the corresponding language, and the text the referenced text.

13.5 Encoding

The Encoding Property is defined by this specification and used for Variables, independent of the VariableType. The BrowseName is “Encoding” and the DataType an EncodingEnum (see 12.4.1).

When the IODD CharacterEncodingT is mapped to the Property, the UA-ASCII value shall be mapped to ASCII_0 and the UTF-8 value to UTF8_1.

13.6 DisplayFormat

The DisplayFormat Property is defined by this specification and used for Variables, independent of the VariableType. The BrowseName is “DisplayFormat” and the DataType a String. It contains the String as defined in the IODD as displayFormat.