Formazin Calibration Procedure - Hach 2100AN IS User Manual

Formazin calibration procedure

For the best accuracy, use four matched sample cells or the same sample cell for all measurements during calibration. Refer to
on page 21.
1. Push CAL/Zero. 2. Rinse a clean
sample cell two times
The CAL/Zero light
with dilution water. Fill
turns on, and the mode
the sample cell to the
display shows "00" .
line (about 30 mL) with
The NTU value of the
dilution water and
dilution water used in
immediately put the cap
the previous calibration
on the sample cell. Use
is shown.
the same dilution water
that was used to
prepare the formazin
standards.
40 English
3. Clean the sample 4. Apply a small bead
cell with a soft, lint-free of silicone oil from the
cloth to remove water top to the bottom of the
spots and fingerprints. sample cell.
Do not invert the
sample cell.
Matching sample cells
5. Use the oiling cloth 6. Put the sample cell
provided to apply the oil in the sample cell
equally to the surface of holder with the triangle
the sample cell. on the sample cell
Remove the excess oil. aligned with the
Make sure that the reference mark on the
sample cell is almost sample cell holder.
dry. Close the cover.