In-Situ TROLL 9500 Operators Manual - Manual (Page 99)

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TROLL 9500 Operator’s Manual 0095110 rev. 007 01/09
Allow 5-10 minutes for temperature and oxygen equilibration.
TIP: The equilibration time depends on the condition of the
water with respect to temperature and exposure to air.
2. Connect the TROLL 9500 to a PC and establish a connection in
Win-Situ 4 or Pocket-Situ 4. Win-Situ screens are illustrated here.
The Pocket-Situ interface is similar, with the Navigation tree at the
top and the Information pane below it.
3. Select the TROLL 9500 in the Navigation tree. The software will
automatically detect and display the installed sensors.
4. Select Rugged Dissolved Oxygen in the Parameters list.
Information on the RDO sensor is shown, including its serial num-
ber (SN), the foil batch number, and recent calibration information,
as shown in the large screen at the bottom of the page.
5. Select Calibrate.
6. Before the RDO Calibration Wizard starts, you will be asked how
you want to handle barometric pressure. See the sidebar on
page 93.
CALIBRATION SOLUTIONS
100% DO calibration is performed in water saturated with air. For best
results, use the In-Situ RDO Bubbler Cal kit (Cat. No. 0048580).
0% DO calibration is performed in an oxygen-depleted solution. So-
dium sulfite (Na
2
SO
3
, Catalog No. 0017670) is available from In-Situ
Inc. Bubbled nitrogen may be used; in this case allow plenty of time
for the oxygen to be completely purged from the water.
RECOMMENDED CALIBRATION FREQUENCY
Calibration frequency is more predictable than with electrochemical DO
sensors, since the sensor does not drift appreciably. If the foil is not me-
chanically damaged or removed, calibration can last three months or more.
TIP: For best results, check the RDO sensor several times
per year in 100% air-saturated water.
TRADITIONAL 2-POINT CALIBRATION
Ideally, the RDO sensor should be calibrated under stable and con-
trolled conditions, like those found in a laboratory setting. However,
field calibration can also be performed. Calibration solutions should be
close in temperature to the sample matrix.
One or two calibration points can be taken. If only one point is taken,
the software uses the results of a previous calibration for the other point.
A 2-point calibration (100% and 0%) is recommended
s
OXYGEN SATURATION POINT
1. Submerge the RDO sensor in a container of clean water aerated
with the In-Situ bubbler. Ensure that the sensor is completely
submerged and the sensor cap is not directly in the bubble stream.
4
5
Full Screen button
TIP: To see all of the infor-
mation pane, you can click
the “Full Screen” button on
the Win-Situ toolbar.
Device clock
SECTION 13: DISSOLVED OXYGEN—OPTICAL