Thermo Scientific AquaSensors™ DataStick™ Measurement System User Guide
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When the calibration is complete, the abort option is no longer available.
When the point has been successfully calibrated, measured values will be based on the new calibration. The rate of
change in reading from the old measured value to the new will be dependent on the sensor filter value that is entered
in the configuration menu.
Exiting the calibration menu will return the user to the measure screen.
ASCII Command to Initiate a pH 1-Point Buffer Calibration
Function
Command
Explanation
1-Point Buffer
CALS1PB
Initiates a 1-point calibration for pH sensors
All Calibration Commands will respond with “OK” if accepted and “ERROR” if not accepted
The status of the calibration can be reviewed with the CALSTATUS command. When the last number returned is a 1,
the calibration is in process. When the last number returned is a 2, the calibration has been successful. Any other number
indicates a specific failure mode (see appendix).
4 . 1 . 3 . 2
2 - P O I N T B U F F E R M E T H O D
Select 2-POINT BUFFER from the calibration menu to begin a pH calibration sequence.
A 2-point buffer calibration is the recommended calibration method for most accurate results and requires 2 buffer standards
at least 3 pH units apart. Every pH sensor is calibrated this way when it leaves the factory and will maintain accuracy for a period
of time when the sensor head is kept wet.
Either Thermo Scientific AquaSensors pH standards or DIN pH standards can be selected from the configuration menu for this
calibration method. This process allows calibration to be done without entering any numbers but requires that the buffer standards
used for the calibration match the standard family that is selected in the configuration menu. The default standards are 4 pH, 7 pH
and 10 pH.
