Turb
®
750 T
Operation
11
ba77234e04
07/2022
During sampling, ensure all movement is kept to a minimum
If necessary, vent the sample (ultrasonic baths, heating or adding a sur-
face-active substance to reduce the surface tension)
Measuring the turbidity
NOTE
Never pour any liquids directly into the cell shaft. Always use a cell for
measurement. The meter only measures precisely if the cell is closed
with the black light protection cap and aligned with the marking of the
measuring position determined.
For quick and easy measuring we recommend that you use marked cells (see
P
, page 9).
If your cells are not marked you can determine the suitable position of the
individual cells in the cell shaft while measuring.
The outside of the cell always has to be clean, dry, and free of
fingerprints and scratches. Clean the cells before starting to
measure (see C
, page 15). Only hold the cells
by the top or by the black light protection cap.
With turbidity values under 1 FNU/NTU, the measured value is
strongly influenced by the cell and its alignment.
To increase measurement accuracy with turbidity values under 1
FNU/NTU, calibration in the 0.02 FNU/NTU standard and later
measurement should take place in the same cell.
1 Clean the cell (see C
2 Rinse the cell:
Pour approximately 10 ml sample into the cell. Close the cell and
rotate it several times before throwing the sample away.
3 Repeat the rinsing procedure twice more.
4 Fill the cell with the sample to be measured (approx. 15 ml). Close
the cell with the black light protection cap.
5 Insert the cell.
6 Align the marking on the cell cap with the marking at the cell shaft.
or
Determine the suitable position of the cell in the cell shaft (see
D
7 Press the
<START/ENTER
(.)
>
key.
Measurement starts. The measured value is displayed.
