Hanna Instruments HI 96711 - Manual (Page 8)

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• Press RANGE/GLP/ to change the range.
The range can be changed any time when the
instrument is in
measurement mode.
The selected range is memorized and the selection
remaines unchanged at power off or when the
battery is removed.
Code Parameter
P1 Free Chlorine
P2 Total Chlorine
The HI 96711 can measure Free chlorine when range P1 is selected or Total chlorine when
range P2 is selected. To change the active range follow the procedure:
• Turn the meter on by pressing ON/OFF. The
display briefly shows all tags on.
• After startup, the range identification number is
displayed on the secondary LCD as P1 or P2.
RANGE SELECTION
STARTUP
Prepare the instrument for measurement as follows:
• Unpack the instrument by removing the dust protection sleeve from the instrument cuvette
holder.
• Place the battery in the instrument as described in the “BATTERY REPLACEMENT” chapter.
• Place the instrument on a flat table.
• Do not place the instrument under direct sun light.
• It is important that the sample does not contain any debris.
This would corrupt the reading.
• Each time the cuvette is used, the cap must be tightened
to the same degree.
• Whenever the cuvette is placed into the measurement
cell, it must be dry outside, and completely free of
fingerprints, oil or dirt. Wipe it thoroughly with HI 731318
or a lint-free cloth prior to insertion.
• Shaking the cuvette can generate bubbles in the sample, causing higher readings. To obtain
accurate measurements, remove such bubbles by swirling or by gently tapping the cuvette.
• Do not let the reacted sample stand too long after reagent is added, or accuracy will be lost.
• It is possible to take multiple readings in a row, but it is recommended to take a new zero
reading for each sample and to use the same cuvette for zeroing and measurement.
• After the reading it is important to discard immediately the sample, otherwise the glass
might become permanently stained.
• All the reaction times reported in this manual are referred to 20°C (68°F). As a general rule
of thumb, they should be doubled at 10°C (50°F) and halved at 30°C (86°F).
• In order to maximize accuracy, prior to a measurement follow the validation procedure to
be sure that the instrument is properly calibrated. If necessary, calibrate the instrument.