Thermo Scientific AquaSensors™ DataStick™ Measurement System User Guide
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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 1-Point Sample Calibration
Function
Command
Explanation
1-Point Sample
CALS1PS
Initiates a 1-point calibration
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).
4.2.4
ORP Sensor Maintenance
In order to maintain accurate measurement values, the sensor will need occasional maintenance. The harsher the process, the more
maintenance the sensor will require. Proper and regular maintenance will yield a longer sensor life.
The recommended ORP sensor cleaning procedure is as follows:
1.
Remove sensor from service and rinse or spray it with warm water to remove heavy deposits.
2.
Soak the sensor in a container of hot detergent water for 30 minutes. Do not use detergents that contain oily skin softeners
like aloe or lanolin that can coat the glass electrode. Powdered Alconox™ and Dawn™ dishwashing liquid work well.
3.
Use a soft-bristled brush, such as a soft toothbrush, and hot detergent water to scrub the entire electrode end of the sensor,
being careful not to scratch or break the glass electrode.
4.
Rinse the electrode end with clean warm water.
5.
If deposits are still present on glass electrode repeat steps 2 and 3. In the case of lime or other mineral deposits a weak
solution (about 0.1 M) of hydrochloric acid may be used. In some cases, a dilute solution (about 10:1) of water and chlorine
bleach or a solution of water and EDTA may also work. Stubborn oil or grease deposits may require cleaning with a solvent
such as acetone or alcohol. Assure that the sensor body in compatible with the solvent. Protein deposits may be cleaned with
a pepsin-based cleaning solution. Bacterial or mold growths may be removed with dilute chlorine bleach.
