5.1.6.5 Structured value

Structured data element is defined in custom DataType derived from Structure DataType or is represented by nested VariableType that has Variables as children.

  1. A structured data element represented as flattened Property Name

  2. Struct Simple {

  3. Integer Position;

  4. Float LastValue;

  5. Boolean Exists;

  6. String Comment;}

  7. ISA-95: Simple.Position, Simple.LastValue, Simple.Exists, Simple.Comment

OPC UA: ABC DataType (custom DataType) derived from Structure DataType is defined, with the given structure.

  1. A structured data element represented by creating an ISA95Property with no data value with nested child ISA95Properties and identification of element.

  2. Struct Simple {

  3. public int Position;

  4. public double LastValue;

  5. public bool Exists;

  6. public string Comment;}

  7. ISA-95: Property [ID=”Simple”]

  8. Property [ID=”Simple”]\ Property [ID=”Position”]

  9. Property [ID=”Simple”]\ Property [ID=”LastValue”]

  10. Property [ID=”Simple”]\ Property [ID=”Exists”]

  11. Property [ID=”Simple”]\ Property [ID=”Comment”]

OPC UA:All ISA95Properties are represented as Variables and Simple property points to Position, LastValue, Exists, and Comment properties by HasComponent or subtypes of HasComponent ReferenceType. (See clause 4.3.8.6)

A combination of a) and b) where a structured data element represented by creating a ISA95 Property with a data value that is a structured data element and with nested child properties and identification of element (see Figure 14). This is the preferred method for modelling complex information. [Note: the figure flow the template defined in OPC 10000-3 with some extensions defined in Annex F]

Figure 14 - Complex Data Mapping