34
CALIBRA
TION
Salinity Calibration Procedure
The measurement of salinity is based on the Practical Salinity Scale which uses the EC measurement.
If the user has a standard with known PSU value it may be used to calibrate the conductivity sensor.
1. Remove the shield from the probe. Rinse the probe with purified water.
2. Fill the calibration beaker 2/3 full with salinity standard of a known value.
3. Immerse the sensors in solution. Raise and lower the probe several times. Discard this solution.
4. Fill the calibration beaker 2/3 full with the salinity standard.
5. Slowly place the sensors in the solution. Dislodge bubbles that may adhere to the sensors.
6. Wait a few minutes for the measurement to stabilize. Use the arrow keys to select “Salinity”
from the Conductivity Calibration list and press
Select
to start the calibration. A text box window
will appear. Use the keypad to enter the value of the standard (5.00 to 70.00 PSU) at the
current temperature. Press
Accept
to confirm the standard value.
7. The stability timer will count down until the display shows the “Ready” message.
8. Note the temperature and adjust the salinity value if needed.
9. Press
Confirm
to save calibration. “Storing” followed by “Calibration completed” is displayed.
10. Press
OK
to return to the calibration menu or
Measure
to return to the measurement screen.
Notes:
These procedures calibrate the slope value. To calibrate the offset, set the calibration point
at 0 μS/cm and repeat the procedure.
Salinity Calibration Error Messages
• “Invalid temperature”: temperature input is not within the acceptable range (0 to 50 °C).
• “Wrong standard”: conductivity input is not within the acceptable range.
