Indexing a single sample cell – Hach-Lange 2100 N IS Laboratory Turbidimeter User Manual User Manual
Page 19
Indexing a single sample cell
When measuring very low turbidity samples, use a single indexed sample cell or a flow cell for all measurements to get precise and repeatable
measurements. As an alternative, optically matched sample cells can be used. Refer to
on page 19. Matched sample cells do
not provide as good of accuracy and precision as a single indexed sample cell that is used for every measurement or a flow cell.
1. Rinse a clean,
empty sample cell two
times with dilution water
and drain to waste. Fill
the sample cell to the
line (about 30 mL) with
dilution water and
immediately put the cap
on the sample cell.
Refer to
on page 20.
Let the sample cell sit
for at least five minutes
to degas.
2. Clean the sample
cell with a soft, lint-free
cloth to remove water
spots and fingerprints.
3. Apply a small bead
of silicone oil from the
top to the bottom of the
sample cell.
4. Use the oiling cloth
provided to apply the oil
equally to the surface of
the sample cell.
Remove the excess oil.
Make sure that the
sample cell is almost
dry.
5. Put the sample cell
in the sample cell
holder. Close the cover.
Record the value when
stable.
6. Remove the sample
cell, turn it about
1
/
8
of a
turn and put it in the
sample cell holder
again. Close the cover.
Record the value when
stable.
English 17