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 55.

Table 55 – CalibrationValueType Definition

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.