Principles of Operation
Teledyne API – Model 430 Compact Ozone Analyzer
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08311C DCN7342
5.
PRINCIPLES OF OPERATION
Refer to Figure 5-1 for pneumatics and Figure 5-2 for electronics.
The Model 430 ozone analyzer measures ozone using UV absorption to calculate the
concentration of ozone flowing through the sample path. The Model 430 uses a mercury
lamp constructed to emit UV light at 254nm wavelength. This light shines down a
hollow quartz tube that is alternately filled with sample gas, then filled with gas
scrubbed to remove ozone in order to achieve a stable and accurate measurement. The
flow is driven by a small sample pump inside the instrument and is controlled using a
precision flow orifice.
Between the sample gas and the scrubbed gas, the intensity of the light is measured and
compared as a ratio I/Io, using the Beer-Lambert equation. This ratio forms the basis for
the calculation of the ozone concentration. (The Beer-Lambert equation factors the
temperature, the pressure, and other parameters that also influence the density, thereby
providing the true concentration of ozone.)
Figure 5-1. Model 430 Pneumatic Diagram
Summary of Contents for 430
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