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6.22 Temperature and Conductivity Calibration
Temperature
The temperature sensor does not have specific calibration procedure. However, you should verify that
the sensor is reading correctly by checking it against a precision certified thermometer.
Conductivity
Follow these steps to calibrate the conductivity sensor for conductivity, specific
conductance, salinity, and total dissolved solids.
1. Always service and clean the conductivity sensor before calibration (see
Section 2.10.2 in 6-Series User Manual).
2. Use a standard that is 1000 µS/cm or greater.
3. Rinse with water and pre-rinse with calibration standard. Then fill the cal cup with the recommended
standard volume.
4. In the ‘Main’ menu, enter ‘7’ (Sensor).
5. Ensure that temperature and conductivity are active. Active sensors are designated by an * (asterisk).
6. Return to the ‘Main’ menu once you have selected or deselected the appropriate sensors.
7. Enter ‘2’ (Calibrate).
8. Enter the number for ‘Conductivity.’
9. Enter 1 (SpCond-Special Conductivity).
10. Ensure that the conductivity cell is completely submerged and does not contain any air bubbles.
11. The screen will prompt you to enter the value of your standard in mS/cm. (The number in parentheses is the
value of the last solution used to calibrate conductivity. Press enter to use this value.)
The value prompt is for MILLIsiemens (mS) not microsiemens (µS). 1000 µS = 1mS.
12. Input the value of the calibration standard in millisiemens, then press ‘Enter.’
13. Observe the value, and once the signal has stabilized for approximately 30 seconds, press ‘Enter’ to accept the
calibration.
14. Return to the ‘Main’ menu.
15. Enter ‘8’ (Advanced).
16. Enter ‘1’ (Cal constants).
17. Conductivity should read 5 ±0.5.
If the conductivity probe does not fall in this range, ensure:
• The probe is clean (see Section 2.10.2 in 6-Series User Manual)
• The probe is not damaged
• The calibration standard is not contaminated
Conductivity calibration is complete. Empty the calibration cup and rinse the sensors.
NOTE
6.2