Hach DR/700 Procedures Manual page 392

HARDNESS,
7.
Install module
number
52.01
in a DR/700.
continued
8.
Press: I/O
The display will show
525 nm
and module number
52.01
52-66
9.
After 2 seconds,
the display will show
a program number,
the concentration
units, decimal
position and the zero
prompt. If necessary,
press the
UP ARROW
key until the lower
display shows
program number
52.10.1
for magnesium as
CaCO .
3