Hanna Instruments HI 88713 - Manual (Page 10)

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NORMAL MEASUREMENT
This type of measurement is best suited for regular readings, when the sample is stable and normal
accuracy is required. In normal mode, the measurement takes about 10 seconds and the lamp is ON
for a minimum period of time (about 7 seconds).
CONTINUOUS MEASUREMENT
This measurement mode is suitable when many measurements have to be taken in a short period of
time. The mode is useful to evaluate a very fast settling sample. This measurement mode is
recommended for indexing cuvettes.
• Press “Read” functional key to take the
measurement.
The display will show “READ” in the left side
and blinking dashes. The dashes and light icon
will appear during different measurement
phases.
• The result is displayed in the selected units.
• Press “Read” functional key to take the
measurement.
The display will show “READ” in the left side and
blinking dashes. The dashes and light icon will
appear during different measurement phases. The
first value is displayed after 10 seconds and then a
new average of the available readings is displayed
each second. When a new value is displayed, the
measurement value will blink briefly. The last averaged
value remains on the display at the end of the
measurement.
• Replace the cap.
• Wipe the cuvette thoroughly with a lint-free
cloth to remove any fingerprints, dirt or water
spots.
• Apply silicone oil on the cuvette and wipe with
a lint-free cloth to obtain an even film over the
entire surface of the cuvette.
Note: It is very important to oil the cuvette, espe-
cially for low turbidity values (< 1 FNU)
to hide the glass imperfections which can
influence the reading.
• Place the cuvette into the instrument. Align the
mark from the cuvette with the sign on the
instrument top
• Close the lid.
Note: If you have a cuvette with indexing mark,
place the cuvette into the instrument with
the indexing mark aligned with the sign on
the instrument top.
• Press “Read” functional key and keep it pressed to take continuous readings.
The display will show “READ” in the left side and blinking dashes. The dashes and light icon will
appear during different measurement phases. The first value is displayed after 10 seconds and then
a new reading is displayed each second as long as the “Read” functional key is kept pressed. When
a new value is displayed, the measurement value will briefly blink.
The last value remains on the display after the “Read” functional key is released.
AVERAGED MEASUREMENT
This measurement mode is useful when samples that cause unstable readings are analyzed. By
averaging several readings, noise effect is reduced and accurate measurements can be taken.
This mode can also be selected when high accuracy measurements are needed. In the average mode
10 measurements are averaged in a short period of time (about 20 seconds).
To use the averaged reading mode first enter setup and enable the Average reading mode. The “AVG”
text will be displayed in the left side of the screen.
The HI 88713 Turbidity bench meter automatically
selects the correct turbidity range to display the
results with the highest accuracy. In FNU and NTU
Non-Ratio Turbidity Modes, if the measured value
is higher than 1000 FAU, the display will show
the maximum value blinking and the message “Out
of range” on the message line. For FAU Turbidity
and NTU Ratio Turbidity modes, if the measured
value is higher than 4000 FNU/NTU (980 EBC),
the display will show the maximum value blinking
and the message “Out of range” on the message
line.