7.5.1 CalibrationValueType
The CalibrationValueType is a subtype of the DataItemType. It represents the specific quantity and value (with engineering unit) that a calibration target provides for calibration of equipment. The VariableType is formally defined in Table 57.
| Attribute | Value | |||||
| BrowseName | CalibrationValueType | |||||
| IsAbstract | False | |||||
| ValueRank | −2 (−2 = Any) | |||||
| DataType | 0:Number | |||||
| Description | Represents the specific quantity and value (with engineering unit) that a calibration target provides for calibration of equipment. | |||||
| References | NodeClass | BrowseName | DataType | TypeDefinition | Other | |
|---|---|---|---|---|---|---|
| Subtype of the 0:DataItemType defined in OPC 10000-8, i.e. inheriting the InstanceDeclarations of that Node | ||||||
| 0:HasProperty | Variable | 0:EngineeringUnits | 0:EUInformation | 0:PropertyType | M | |
The CalibrationValueType inherits the Properties of the DataItemType. That does include the optional 0:ValuePrecision, defining the precision of the calibration value.
The mandatory 0:EngineeringUnits defines the engineering unit of the calibration values.
Remark: The quantity of the calibration value is of importance. This specification waits for this to be solved in the base OPC UA specification (OPC 10000-8), and will use this afterwards.
The VariableType can be used with an (multi-dimensional) array or scalar values. When a calibration target provides several independent values, e.g., lengths, that can be used for calibration, each one should get its own instance of CalibrationValueType. If the calibration target provides for example a scale for length, the CapacityRangeType should be used. The array of the CalibrationValueType shall only be used, when it represents one overall value consisting of a number of distinct values for example the spatial frequency of line pattern blocks on a resolution test chart for calibration of optical instruments.