Ametek AMEVision 3050-TE, Руководство пользователя

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1-2 | 3050-TE Moisture Analyzer
Figure 1-2
3050 Analyzer Flow
Diagram.
coating absorbs moisture from the gas stream, changing the mass of the coating.
Changes in the mass are detected as changes in the natural resonance frequency of
the oscillator.
In the analyzers normal operating mode, the QCM sensor is alternately exposed to
the sample gas and a dry reference gas. A dry reference gas is produced by passing a
portion of the sample gas through a dryer to remove any moisture present (i.e. - the
moisture content of the dry reference is less than 0.010 ppmv). The difference in
the resonant frequency of the QCM sensor, as measured when exposed to each of
the two gas streams, is a function of the moisture content of the sample gas. Thus,
the moisture concentration of the sample gas is determined from this frequency
difference. The calibration data, which relates the moisture concentration of the
gas stream to the measured frequency difference, are stored in an EEPROM within
the QCM sensor module.