Hach DR/850, Procedures Manual, Page: 209 / 460

209
Using AccuVac Ampuls
1.
Enter the stored
program number for iron
(Fe)- AccuVac Ampuls.
Press:
PRGM
The display will show:
PRGM ?
Note: For most accurate
results, perform a Reagent
Blank Correction using
deionized water (see
Section 1).
Note: Adjust the pH of
stored samples before
analysis.
2.
Press:
39 ENTER
The display will show
mg/L, Fe and the
ZERO icon .
Note: Total iron
determination needs a
prior digestion. Use any of
the three procedures in
Digestion (Section 2).
3.
Fill a sample cell
with at least 10 mL of
sample (the blank).
Collect at least 40 mL of
sample in a 50-mL
beaker.
Note: Sample pH is
important in this test; see
Interferences.
Note: Rinse glassware with
a 1:1 hydrochloric acid and
deionized water before use
to avoid errors due to iron
deposits on the glass.
4.
Fill a TPTZ Iron
AccuVac Ampul
with sample.
Note: Keep the tip
immersed while the ampul
fills completely.
5.
Invert the ampul (the
prepared sample)
repeatedly to mix. Wipe
off any liquid or
fingerprints.
Note: A blue color will
develop if iron is present.
6.
Press:
TIMER ENTER
A three-minute reaction
period will begin.
7.
Place the blank into
the cell holder. Tightly
cover the sample cell
with the instrument cap.
8.
Press:
ZERO
The cursor will move to
the right, then the
display will show:
0.00 mg/L Fe
Note: Press EXIT to zero
the instrument while the
timer is running.
Note: If Reagent Blank
Correction is on, the
display may flash “limit”.
See Section 1.
IRON, TOTAL,
continued