In-Situ TROLL 9500 Operators Manual - Manual (Page 26)

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0095110 rev. 007 01/09 TROLL 9500 Operator’s Manual
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Accept button becomes available when NOMINAL or STABLE is
indicated for all 3 parameters.
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plete. Go to step 14.
If performing a Polarographic Dissolved Oxygen calibration,
continue with steps 10-13.
10. Polarographic Dissolved Oxygen: Before the D.O. segment of
the Quick Cal Wizard starts, you will be asked how you want to
handle barometric pressure.
Barometric pressure is important in converting measurement of
D.O. concentration to percent saturation, and a value is required
for accurate calibration. If the TROLL 9500 cable is vented, an
accurate barometric pressure value can be read from the onboard
barometric pressure sensor. If the TROLL cable is non-vented,
then a barometric pressure value should be entered manually.
Do one of the following in this screen:
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surements using vented cable, click No — and you may want to
check the “Don’t ask me this again” box.
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on non-vented cable, click Yes. In the Edit Barometric Channel
screen, check the box indicating non-vented cable for measure-
ments but vented cable for calibration/programming.
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surements on non-vented cable, click Yes. In the Edit Baromet-
ric Channel screen, check the box indicating non-vented cable
for measurements and enter a barometric pressure value. For
help, see Section 9, Monitoring Barometric Pressure.
SECTION 3: GETTING STARTED
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11. To complete the calibration, expose the polaro-
graphic D.O. sensor to air: Without discon-
necting the cable, invert the probe so that the
membrane at the tip of the sensor is in air and
THE
While you have the cap off, remove any drop-
lets on the membrane by blotting gently with a
clean swab or the corner of a tissue. Re-attach
the end cap loosely to insure the volume is not
pressurized.
TIP: For proper venting, loosen the end cap until a small
hole in the threads near the o-ring is at least partly visible.
12. In the DO calibration screen, select the membrane type, stamped
ON
13. Click Run to begin the stabilization.
The display will continuously update as readings are taken and
compared against the stabilization criteria (see sidebar on the
previous page).
14. When the sensor response is STABLE (or alternatively, when you
accept the nominal value), the Quick Cal procedure is complete.