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• Turn the instrument on by toggling ON/OFF switch. When the main screen appears the instrument
is ready.
• Make sure that the correct range is selected free or total chlorine. If necessary, press
RANGE
to
select the correct range.
• Press the
CAL CHECK
key and a screen with
GLP information is displayed including the serial
number and the last calibration time.
• Press the
Chk
key to start the check procedure.
INTERFERENCES
The colorimetric measurements are affected by the following interfering agents:
• Bromine (positive error).
• Chlorine dioxide (positive error).
• Iodine (positive error).
• Oxidized Manganese and Chromium (positive error).
• Alkalinity above 250 mg/L CaCO
3
or acidity above 150 mg/L CaCO
3
will not reliably develop the
full amount of color or it may rapidly fade. To resolve this, neutralize the sample with diluted
HCl or NaOH.
• In case of water with hardness greater than 500 mg/L CaCO
3
, shake the sample for approximatively
2 minutes after adding the powder reagent.
Note:
It is recommended to zero the meter before
each measurement.
CAL CHECK PROCEDURE FOR FREE/TOTAL CHLORINE
The
HI 83414
free and total chlorine colorimeter has a powerful CAL CHECK function that allows the
user to check the instrument calibration against a NIST traceable standard before making a set of
measurements. With the same standard, the instrument could be re-calibrated, if necessary.
Note:
Free and total chlorine must be calibrated separately. Calibration of one range will not
calibrate the other range.
VALIDATION PROCEDURE
