Campbell Scientific RTDAQ Software - Manual (Page 268)

Section 9. Calibration and Zeroing
Select the sensor you wish to calibrate, press Next.
If the variable is configured as an array of sensors, you may select an
individual item to calibrate only that element, or you can select the entire array.
Now you can monitor the reading on the sensor to be calibrated. Set the sensor
to the zero condition, and press Calibrate.
The Current Value box will be yellow during the calibration process. When it
finishes, you will see the new value of the sensor after the application of the
zeroing offset. Press Finish to end the calibration.
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