Teledyne 2010A - Split architecture thermal conductivity analyzer - Manual (Page 90)

2 Installation Model 2010A
2-4: Part II Teledyne Analytical Instruments
vented to the same area, both VENT lines must vent to areas with equal
ambient pressures, and pressures must vary no more than the normal baro-
metric changes.
2-6 SAMPLE Gas
In the standard model, sample and calibration gases are introduced
through the SAMPLE fitting. The gases must be Tee'd into the Sample inlet
with appropriate valves.
The gas pressure in should be well regulated. The sample line pressure
regulator should be installed as close to the sample line as possible to mini-
mize sample line lag time.
If greater flow is required for improved response time, install a bypass
in the sampling system upstream of the analyzer input.
2-7 REFERENCE Gas
A gas of fixed composition is needed as a reference to which the
sample gas will be compared. The reference gas is normally selected to
represent the main background gas of the analysis.
For most applications, a constant supply of reference gas flowing at the
same rate as the sample is required for best results. However, in many cases
the flow of reference gas can be slowed to about 0.08 scfh (40 cc/min) with
good results.
For some applications, an optional sealed air reference is installed. In
sealed-reference sensors the reference side of the detector cell is filled with
air and sealed. This eliminates the need to have reference gas constantly
passing through the cell.
NOTE:For instruments equipped with the optional sealed air refer-
ence, there is no REFERENCE inlet or reference VENT port.
It is highly recommended that the same cylinder of gas be used for both
the REFERENCE gas and the ZERO gas.
Pressure, flow, and safety considerations are the same as prescribed for
the SAMPLE gas, above.