Teledyne 200A, Instruction Manual, Page: 161 / 220

Teledyne API Model 200A NO
X
Analyzer Instruction Manual, 02246, Rev. F1
The reaction cell pressure compensation factor is equal to 1.0000 when the cell pressure is 5"-
Hg-A. The compensation factor increases sample concentration with increasing cell pressure to
compensate for increased quenching of the chemiluminescent reaction at higher pressures. The
pressure compensation correction has been found to work adequately up to about 8000 ft
(2400m) altitude.
The sample pressure compensation factor is equal to 1.0000 at 29.92"-Hg-A. This factor
increases sample concentration with decreasing sample pressure to compensate for a lower head
pressure on the sample flow orifice.
Taken together, the three factors change the output of the instrument very little. The sample
temperature is essentially invariant, and the cell pressure and sample pressure factors tend to
cancel each other. The resultant coefficient has no practical variation with pressure changes due
to weather fronts. Changes in altitude of 1000 feet usually change the output of the instrument by
about 0.5% if compensation is turned off, much less if it is operating.
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