Campbell Scientific RTDAQ Software - Manual (Page 261)

Section 9. Calibration and Zeroing
The following values of the mode variable are used to initiate a calibration
process:
1 Start the calibration, OR start the first point of a two point calibration
4 Start the second point of a two point calibration
For Zeroing and Offset calibration, a mode value of 4 is never
used. The entire calibration process is initiated with the mode
value being set to 1. NOTE
By properly changing the known value variables and the mode variables in a
calibrating program, a manual calibration can be performed on a sensor. Steps
for doing this are given below.
9.4.2 Using the Mode Variable for Manual Single-Point
Calibration
These steps demonstrate how to perform manual single-point calibrations
(Zeroing or Offset calibrations):
1. Ensure the status (value of the mode variable) is 0 or 6 before you start.
a. A number greater than 0 that is not 6 indicates that a calibration is in
progress or that the last calibration did not complete properly.
b. A number less than 0 indicates that the calibration process
encountered an error. Resolve the error before proceeding with the
calibration then set the mode value to zero for a fresh start.
2. Place the sensor into the zeroing or offset condition.
3. Indicate the known offset value (if applicable) by changing the “known
value” variable to that value.
4. Set the mode variable to 1 to initiate the calibration process.
5. Note that the datalogger automatically sets the mode variable to 2 during
the calibration process.
6. Note that the mode variable is set to 6 automatically by the datalogger
when the calibration process completes.
9.4.3 Using the Mode Variable for Manual Two-Point Calibration
These steps demonstrate how to perform manual two-point calibrations
(Multiplier/Offset or Multiplier Only):
1. Ensure the status (value of the mode variable) is 0 or 6 before you start.
a. A number greater than 0 that is not 6 indicates that a calibration is in
progress or that the last calibration did not complete properly.
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