Hach DR/700 - Page 279

50-29
NITRATE, HR, continued
USING ACCUVAC AMPULS
1. Install module
number
50.01
in a DR/700.
Note: If sample cannot
be analyzed
immediately, see
Sampling and Storage
following these steps.
Adjust the pH of stored
samples before analysis.
2. Press: I/O
The display will show
500 nm
and module number
50.01
3. 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
50.06.1
4. Fill a cell with
10 mL of sample (the
blank). Cap. Collect
at least 40 mL of
sample in a 50-mL
beaker.
5. Fill a NitraVer 5
Nitrate AccuVac
Ampul with sample.
Note: Keep the tip
immersed while the
ampul fills completely.
Note: For proof of
accuracy, use a 10 mg/L
Nitrate Nitrogen
Standard Solution
(listed under Optional
Reagents) in place of
the sample.
6. Invert the ampul
repeatedly for one
minute to mix.
Note: Inversion time
and technique influence
color development. For
most accurate results,
make successive tests on
a
10 mg/L Nitrate
Nitrogen Standard
(listed under Optional
Reagents). Adjust
inversion time to obtain
the correct result.
1 minute