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5.4.3 Chlorine Electrode Calibration
NOTE:
Calibrate the free chlorine sensor after operating at least 1 hour. Check for
calibration after 24 hours of operation. If required, perform another calibration.
NOTE:
Reliable chlorine testing device is required for proper calibration of chlorine
electrode.
1. Open the water sampling valve.
2. Test the water sample for chlorine using a digital photometer or other reliable
external device.
3. Press m
enu until “Cl Calibrated to” (#6) appears in the LCD display.
The top line will display “Cl Calibrated to” and a number. The number displayed
is the last value entered for the calibration.
The bottom line will display “Cl Sensor was” and a number. This number is the
sensor reading without any calibration at the time of the last calibration.
If there is a large discrepancy between the above two numbers - the sensor
was calibrated improperly or there is a problem with the analyzer.
The analyzer uses the calibrated value, as shown on the main screen, to
determine dosing rates.
4. Press OK.
5. Enter the password. Press the up arrow or down arrow until the password is
reached.
6. Press OK.
7. Press OK again.
The display will now show “Calibrate Cl to” on the top line and “Sensor
Reading” on the bottom line.
The “Sensor Reading” is the current reading of the sensor with no calibration.
The “Calibrate Cl to” value is the new value which you want to set.
8. Press the up arrow or down arrow until the value is the same as the value given
by the digital photometer.
9. Press OK to save the new calibration or Esc to abort without saving.
10. Press Esc to return to the main display.
NOTE:
Chlorine calibration should always be performed within 25% of the set point. If
current chlorine level is 25% above or below the set point, do not perform
calibration until the chlorine level is closer to the set point.
