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MEASUREMENT PROCEDURE FOR RATIO /
NON RATIO TURBIDITY RANGE
To take turbidity measurements, follow the next steps:
• Turn the instrument ON by pressing ON/OFF.
When dashes are displayed on the LCD, the
instrument is ready. The current time appears
on the upper left corner of the display and the
range name appears on the lower right corner.
• Fill a clean, dry cuvette with 10 mL of sample
up to the mark, taking care to handle the
cuvette by the top.
• 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,
especially for low turbidity values (< 1
NTU) 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.
When taking turbidity measurements, several basic rules should be followed:
• Never use cuvettes with scratches or cracks because they can cause inaccurate readings.
• Always cap the cuvettes to avoid spillage of the sample into the instrument.
• Always close the lid of the instrument during measurement.
• Do not use too much oil to prevent contamination of the optical system.
