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5
TURBIDITY MEASUREMEN T
5.1
Sample Vial Handling
a) 6 sample vials are included in the test kit. The cap is marked with 1
#
to 6
#
, and the bottom of the vial
also has the same number. The number of the vial and the cap should always be the same. *Pay
attention that 1
#
and 2
#
vials are only for low turbidity solution measurement. (< 2 NTU)
b) The vial has been rigorously cleaned and sterilized. They can be used directly for the first time. For
subsequent uses, follow the steps below to perform a thorough cleaning.
Clean the inside and outside of the sample vial holder
with detergent → rinse with distilled water
or deionized water multiple times → Rinse the vial twice with the sample solution → Pour the
sample solution into the vial → Close the cap.
5.2
Measurement Preparation
a) Collect the sample solution with a clean container and add the
solution to the 4/5 of the vial (about 18ml), see Diagram 7. Then
close the lid.
b) Before the measurement, users can slowly flip the sample vial a
few times and let it stand for 2 to 5 minutes to eliminate potential
air bubbles (see Diagram 8).
c) Clean off the surface of the vial to ensure it is dry, clean and free
of stains. Apply a small drop of silicone oil on the surface of the vial and wipe it off with a micro-
fiber cloth. Then wipe again with filter paper or high-quality tissue paper. See section 4.1(c) for
details.
5.3
Measurement Mode
a) Normal Measurement Mode
Press , the screen will display the progress bar, and the measured value will be
displayed in 20 seconds. To take the next measurement, press again.
b) TruRead
TM
Measurement Mode
Long press and release the key when you hear a beep (see Diagram 9.1), then enter
TruRead
TM
mode. For example, if the number of continuous measurements is set to 20 times
in parameter setting P2, a measured value will be displayed every 20 seconds. Diagram 9.2
is the third measurement. Diagram 9.3 is the display interface at the end of TruRead
TM
measurement. The average, maximum and minimum values will be displayed along with a
list of 20 measured values. TruRead
TM
measurement mode can be used for observing the
stabilizing process of turbidity, and can also be used for testing rapid-settling solutions.
Diagram 7
Diagram 8
