Hach DR/700 Procedures Manual page 129

OXYGEN DEMAND, CHEMICAL,
COLORIMETRIC DETERMINATION, 0 to 150 mg/L COD
1.
Install module
42.01
in a DR/700.
4.
Fully insert a
COD Vial Adaptor
into the cell holder
with the tabs in the
square slot.
2.
Press: I/O
The display will show
420 nm
and module number
42.01
5.
Clean the outside
of the blank with a
towel.
Note: Wiping with a
damp towel, followed by
a dry one will remove
fingerprints or other
marks.
42-45
continued
3.
After 2 seconds,
the display will show
a program number,
concentration units
and the zero prompt.
If necessary, press the
key until
UP ARROW
the lower display
number shows
42.06.1
6.
Place the blank
into the adapter with
the Hach logo facing
the front of the
instrument.
Note: The blank is
stable when stored in
the dark; see Blanks for
Colorimetric
Determination
following these steps.
Note: Avoid bright light
when making
measurements.