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
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Attribute |
Value |
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BrowseName |
CalibrationValueType |
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IsAbstract |
False |
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ValueRank |
−2 (−2 = Any) |
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|
DataType |
0:Number |
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|
Description |
Represents the specific quantity and value (with engineering unit) that a calibration target provides for calibration of equipment. |
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References |
NodeClass |
BrowseName |
DataType |
TypeDefinition |
Other |
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|
Subtype of the 0:DataItemType defined in OPC 10000-8, i.e. inheriting the InstanceDeclarations of that Node |
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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.
The CapacityRangeType is a subtype of the DataItemType. It is used to represent a scale of calibration values. The value of the Variable defines the range (lowest and highest value), and the resolution the size of each step. The VariableType is formally defined in Table 55.
Table 56 – CapacityRangeType Definition
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Attribute |
Value |
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BrowseName |
CapacityRangeType |
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IsAbstract |
False |
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ValueRank |
−1 (−1 = Scalar) |
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|
DataType |
0:Range |
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|
Description |
Represent a scale of calibration values. The value defines the range (lowest and highest value), and the resolution property the size of each step. |
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|
References |
NodeClass |
BrowseName |
DataType |
TypeDefinition |
Other |
|
|
Subtype of the DataItemType defined in OPC 10000-8, i.e. inheriting the InstanceDeclarations of that Node |
||||||
|
0:HasProperty |
Variable |
0:EngineeringUnits |
0:EUInformation |
0:PropertyType |
M |
|
|
0:HasProperty |
Variable |
Resolution |
0:Double |
0:PropertyType |
M |
|
The CapacityRangeType 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.
The Resolution defines the step size and is used in combination with the Range provided in the Value Attribute to determine, what individual calibration values can be used for calibration.
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.