32 • Measuring Mode, Normal Operation
GX-2012 Operator’s Manual
3. Insert the sample port into the flowing gas. The vent port will allow any excess gas to
release to the atmosphere to avoid damage to pump or sensors.
Figure 16: Purge Tee Fitting
Using the Dilution Fitting
The external dilution fitting is a 1:1 dilution fitting. It is normally used when it is
necessary to introduce air into a sample that has no oxygen or a very low level of oxygen,
such as a nitrogen purged sample. It can also be used when one of the target gas levels in
the sample area will likely be present in a concentration above the detection range for that
gas. Since the fittings partially consist of unplated brass, they are not appropriate for
detection of elevated levels of H
2
S.
1. Start up the GX-2012 as described in “Start Up, Normal Mode” on page 23.
2. Install the dilution fitting to the GX-2012’s quick connect inlet fitting.
3. Connect the tapered rubber nozzle or the sample hose to the GX-2012’s quick connect
inlet fitting.
4. If a sample hose is used, screw the probe onto the sample hose’s threaded fitting.
5. Monitor the sampling area.
NOTE:
The GX-2012 can be calibrated either with or without the dilution fitting in
place. If calibrated without the dilution fitting in place, then display readings
must be doubled to determine the actual gas concentration. If calibrated with
the dilution fitting in place, then a sample bag must be used during calibration,
and the display readings will be the actual gas concentrations.
CAUTION:
If the dilution fitting is in place for calibration, do not use a demand flow
regulator. Use a sample bag. The use of a demand flow regulator with a
dilution fitting when calibrating will result in an inaccurate calibration.
Figure 17: Dilution Fitting
GX-2012 Inlet
Pressurized
Stream
Sample Port
Excess
Pressurized
Sample
Vent Port
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