Hach AutoCAT 9000 Instruction Manual page 123

9.
Add 1.0 g of potassium
iodide (KI).
Press the
CHECK MARK
to confirm.
Note: KI is added in excess;
the precise amount added is
not crucial to the accuracy or
precision of the analysis.
13.
The analysis parameters
that have been stored for the
current Sub-ID may be
edited at this time.
Highlight the appropriate
line and press the
to change one
CHECK MARK
of the analysis parameters or
press 1 to confirm.
Note: Any changes made will
become the new default
parameters for this method
Sub-ID.
Note: These Sub-ID
parameters can be edited here
as 'run-time' settings, or from
the Main Menu as described in
Section 3.5.
Note: This step will be skipped
if autoscaling software is
enabled.
50081_TotalOxidants.fm
10.
Add 1.0 mL of pH 4
acetate buffer.
Press the
CHECK MARK
to confirm.
Note: Acetate buffer is added
to adjust the sample pH; the
precise amount added is not
crucial to the accuracy or
precision of the analysis.
14.
The timer will start,
allowing the electrode to
stabilize before data
collection.
Once the electrode has
stabilized, the AutoCAT will
begin data acquisition and
plot the titration curve.
11.
The timer will start.
This allows a short period of
time for the reagents to mix
before starting the titration.
15.
The Zoom Range
Determination window will
display the titration curve.
Use the navigation buttons to
select and move the cursors
to define the range of data
points for analysis.
Note: Defining the range of
data points excludes
undesirable portions of the
titration curve from
the analysis.
Total Oxidants
12.
Lower the electrode
head onto the beaker rim.
Press the
CHECK MARK
to confirm.
16.
Select type of end point
determination.
Press for Manual.
DEL
Note: Automatic determination
attempts to identify linear
segments without user input
and is not recommended for
this method.
Total Oxidants
Page 121