3-4 | Thermox CG1000 Oxygen Analyzer
To make the required flow connections, follow these steps:
1. Remove the flow of any sample gas into the analyzer (not necessary
on initial installation). Do this by turning the flow knob on the front of
the analyzer fully in a clockwise direction.
This flow knob is a needle valve and cannot act as a shut-off valve.
2. Connect the sample gas to the sample gas inlet (Figure 3-1). The sam-
ple gas inlet is a 1/8” (.32 cm) compression fitting. For best response
time, make the sample line between the analyzer and sample gas as
short as possible and keep the sample tubing diameter as small as pos-
sible.
3. The sample gas outlet on the rear of the analyzer is a 1/4” (.64 cm)
push-to-connect fitting (Figure 3-1). You can either connect exhaust
tubing to this fitting, or simply allow the gas to vent to atmosphere.
The outlet pressure should never exceed 5 psig (345 millibar gauge).
4. Using the Setup/Display key on the CG1000 analyzer front panel, se-
lect Flow Rate for one of the display lines. See Chapter 4 for setting up
flow rates using the display.
5. If operating under a positive pressure that is greater than 15” water
column go to Step 6. If operating below 15” water column, turn the
pump on by selecting Pump Option from the Setup Key. See Chapter
4 for turning on the pump using CG1000 software.
6. Slowly turn the flow knob on the front of the analyzer counterclock-
wise to increase the flow of sample gas to the desired level. If the carri-
er gas for the sample is helium, the flow rate must be between 150 and
200 sccm. For all other carrier gases, the flow rate must be between 125
and 175 sccm.
Use the same flow rate during both calibrations and normal opera-
tions. any pressure variations of the sample gas can lead to flow varia-
tions greater than 25 sccm can cause analyzer readings to fluctuate.
NOTE
