Thermal Conductivity Analyzer | Model 212R |
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2.3.7 Vent Lines.
The sample path, reference path, and an integral bypass system vent from separate ports at the rear of the analyzer. Wherever possible, TAI recommends that the gases be permitted to vent directly to the atmosphere. If it is necessary to carry these gases to a remote area the following precautions must be ob- servedwheninstallingtheventlines:
1)The vent lines must be 1/4" tubing or larger so that no back pressure resultingfromrestrictedflowisexperiencedbythemeasuringcell.
2)The sample and reference paths must vent into an area that experi- ences the same ambient pressure conditions.
3)The ambient pressure at the vent location should undergo no more than normal barometric pressure fluctuations.
4)The vent lines must be installed so that water and dust cannot accu- mulate in them.
Apressuredifferentialexistingatthecellbetweenthereferenceandsample willresultinacorrespondingchangeinoutputsignal. Thereferenceandsample path flowmeters are located upstream from the cell so that both cell paths can vent directly to atmosphere. The random bounce of the floats in the flowmeters, when located downstream from the measuring cell, can produce up to 5% noise ontheoutputsignal.
3.0STARTUP
3.1Preliminary.
The following preliminary steps should be accomplished before apply- ing power or starting gas flow.
1.Check the integral gas control panel and be sure that all valves are closed (fully cw). Do not jam the sample, reference, and bypass metering valves.
2.Place the “RANGE” switch on the #2 position.
3.Set the “SPAN” control to the reading recorded in Section 7 of the manual.
12 | Teledyne Analytical Instruments |
