Campbell 31022, Инструкция по эксплуатации

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Zero Air Generator
5
FIGURE 6-1. Zero Air Generator port configuration
The Test connection pulls air from two inches above the bottom of the bottle of
molecular sieve. This air sample is used to monitor the effectiveness of the
molecular sieve scrubbing the air. Because unscrubbed air enters at the top and
flows downward, the molecular sieve will be consumed from the top down.
Measuring the CO
2
and water vapor from this Test port and comparing the
values to the readings from the bottom of the bottle shows when the molecular
sieve at the top of the bottle has been consumed. If air from the
Test port
contains more CO
2
or water vapor than the air exiting the Out port, the
molecular sieve should be replaced. Molecular sieve 13X with 1.6 – 2.5 mm
bead diameter is recommended. Approximately 450 g is needed to refill the
bottle (see Section
4.1.2 , Replacement Parts
(p. 3)
).
The In port should either be connected to the exhaust side of an IRGA
zero/span shroud or sample cell, left capped (a tee-connection allows entry of
ambient air from under the Zero Air Generator cover, see FIGURE
6-2 ), or left
uncapped. If the Zero Air Generator is used in recirculating mode, the open
port of the tee will keep the IRGA near ambient pressure. The
Out port or
Test port should be connected to the intake side of the IRGA zero/span shroud