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Teledyne API Model 480L O
3
Monitor User Manual
09419A DCN8342
3.5.1 SAMPLE GAS CONNECTION
Sample gas connections are made to the ¼” tube fittings on the outside bottom
panel. For single stream monitors, use the fitting labeled INPUT (Figure 3-6). For
multi-stream monitors, the sample tubing is connected to the fittings labeled
STRM 1, STRM 2, etc. (Figure 3-7).
1/4" O.D. FEP (Teflon
) tubing is recommended to connect the sample source to
the monitor (recommended length
≤ 5
0 feet). Any fittings used in the sample lines
should be constructed of stainless steel or Teflon
.
Note
For best analytical performance, the tubing should be pre-
conditioned to ozone prior to installation to minimize ozone loss
in the sampling lines.
3.5.1.1
S
AMPLE
F
ILTRATION
The most important factor in maintaining an accurate and stable monitoring system
for ozone is the cleanliness of entire pneumatic system leading up to (and including)
the sensor assembly inside the instrument. Provision must be made for keeping dust
and other particulate matter out of the monitor and upstream sample delivery tubing.
The monitor is equipped with an internal particulate filter down-stream of the
selector manifold.
In addition, it is recommended that inlet filters be installed at the inlet of each
sample line. These filters should be constructed of PTFE or other inert material to
avoid degradation of the ozone concentration. Appropriate disposable inlet filters
can be purchased from TAPI Sales.
3.5.1.2
S
AMPLE
S
YSTEM
D
ESIGN IN
H
UMID
E
NVIRONMENTS
Care must be taken in the design of the sampling system to ensure that water vapor
does not condense in the sampling lines or in the instrument itself. The sample lines
should be routed to avoid large temperature gradients along the lines. If sample is
brought from a hot, humid area into a much cooler area, then low power heating
tape should be wrapped around the lines to keep the temperature of the sample lines
up and avoid condensation. The lines should also not have loops or low points
where water could collect.
For applications that require sampling of very humid gas, a Sample Conditioner
and/or a Permeation Gas Dryer may be required to lower sample gas humidity. A
pneumatic block diagram with the locations of these 480L options is shown in
Figure 3-8, followed by a description of each. Please contact the Teledyne API
Sales Department for additional information.
