11
Calibration Procedure
1.
When a new membrane cap is installed, it may take up to 30 minutes before the chlorine probe starts to
register a reading (>0 mg/l). Although the after 2 hours the reading should be mostly stabilized (80-
90%),it is recommended to allow the chlorine probe with new membrane cap to operate for a minimum
of 6 hours before performing an initial calibration.
2.
Collect a sample at the chlorine probe chamber and test for residual chlorine level with an approved
benchtop or handheld device (e.g. DPD test kit). It is important to test a sample taken at the same
location. Write down the test result and immediately proceed to step 3. Note: For greatest accuracy,
consider performing 3 tests and ensure acceptable repeatability, and then average the results.
3.
Calibration is initiated from the Sensor Overview screen which is accessed by pressing Menu and then
selecting the Free or Total chlorine tile.
4.
Press the keypad button directly below the “Calibrate” icon on the display. Then select “Calibrate Span.”
Follow the user prompts.
5.
When prompted to “Enter Calibration Value”, press the center (Select) button to enter Edit mode. This
will cause the text to go from blue to purple and the Home, Options, and Next buttons will turn gray as
seen above. Once in Edit mode, use the arrows on the keypad to adjust the reading to match the DPD
result. Press the center (Select) button again to exit the Edit mode, and then press Next. A prompt will
appear asking if the electrolyte and membrane were replaced. Answer the prompts appropriately.
6.
This completes the calibration. The calibration will need to be verified on a routine basis and should not
exceed 30 days. Local regulations regarding measurement and reporting of residual chlorine levels may
require daily to weekly calibration verification. Consult local agencies (e.g. EPA, DEQ, Health & Safety) for
more info.
