Hach DR/700 Procedures Manual page 485

IRON,
continued
7.
Fill a 25-mL cell
to the 25-mL line
with sample (the
blank). Cap.
8.
Place the blank in
the cell holder.
Note: Typical indoor
lighting permits the
DR/700 to operate with
the cell compartment
cover open. In bright
sunlight it may be
necessary to close the
cell compartment cover.
Transfer 10 mL of the
blank solution to a 10-
mL cell. If the
10-mL cell is used for
the blank, another
10-mL cell must be used
for the sample.
55-37
9.
Press:
ZERO
The display will
count down to 0.
Then the display will
show 0.000 mg/L and
the zero prompt will
turn off.