Campbell Scientific CR9000X Measurement and Control System - Manual (Page 363)

Section 9. Program Control Instructions
Parameter
Data Type
Enter FIELDCAL PARAMETERS
Used to specify the type of calibration that will be performed.
Digit Function
0 Store a Zero value for performing a zero offset
1 Offset Calibration
Function
Integer
2
3 Two Point Calibration; Slope and Offset (Multiplier and Offset)
Two Point Calibration; Slope only (Multiplier only)
MeasVar
Variable
The variable or variable array for the sensor(s) being calibrated. Must be dimensioned large enough to
accommodate the number of Reps.
Reps
Constant or
Variable
Specifies the number of sensors to that will be setup for calibration. Must be equal to either 1 or the size
of the MeasureVar parameter array. When Reps is equal to the size of the MeasureVar array (the
Index parameter must be set to 1); all elements of the MeasureVar array will be calibrated in a single
scan. When Reps is set to 1, a single element of the MeasureVar array, specified by the Index
parameter, will be calibrated.
If the Reps parameter is declared as a variable, the value can be changed during program operation. This
allows the calibration of a complete array at one point, and following up later with a calibration on a
single element of the array. Reps should be initialized to either 1 or the size of the MeasureVar array
prior to starting a calibration. If Reps is set to zero, no calibration will occur for this instruction.
MultVar
Variable
Zero or Offset function: zero can be entered for this parameter (not used).
Two Point: Variable or Variable array which will be populated with the computed Multiplier(s) from the
calibration(s). MultVar should be dimensioned to the same size as the MeasureVar variable array. The
element of the array for the primary calibration is set by the Index parameter. If MultVar is equal to 0
or NAN prior to the calibration, then it will be set equal to1 during the calibration process.
OffsetVar
Variable
Two Point-Slope Only: zero can be entered for this parameter (not used)
All other functions: Variable or Variable array which will be populated with the computed
Offset(s) from the calibration(s). OffsetVar should be dimensioned to the same size as the
MeasureVar variable array. The element of the array for the primary calibration is set by the
Index parameter. If OffSetVar is equal to NAN prior to the calibration, then it will be set
equal to 0 during the calibration process.
Mode
Variable
This variable parameter stores an integer that indicates the current state of the calibration.
This value can be changed through automatic software or manually by the user using a
Keyboard display or using CSI’s Software packages. The only values valid for manual entry
is 1 or 4.
Digit Edge
-1 Error in the Calibration setup
-2 Multiplier set to 0 or = NAN, measurement = NAN
-3 Reps is set to a value other than 0, 1 or the size of the MeasureVar array
0 Calibration has not been done
1 Start Calibration. (For Offset or 2 Point, KnownVar holds first set point)
2 Computing (set by logger)
3 Only for Two Point. Ready to set the KnownVar to the second value
4 Only for Two Point. KnownVar holds the second set Point
5 Only for Two Point. Computing (set by logger).
6 Calibration is complete.
KnownVar
Variable Zero function: 0 can be entered here (not used)
All other functions: Variable array that holds the set point value(s) to be used in the calibration routine.
KnownVar must be dimensioned to the same size as the MeasureVar. The element of the array used for
the first calibration is set by the Index parameter.
Index
Constant or
Variable If Reps is set to the size of the MeasureVar, then Index must be set equal to 1 (complete array will be
calibrated starting with the first element). If Reps is set to 1, then Index specifies which element of the
MeasureVar array will be calibrated.
If Index is declared as a variable, it must be initialized to a non-zero value before a calibration can be
performed.
Avg
Var/Constant Used to specify the number of points (Scans) to average when performing a calibration.
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