Theory Of Operation; Measurement Method - Teledyne T400 User Manual

6. THEORY OF OPERATION

The Model T400 ozone analyzer is a microprocessor-controlled analyzer that determines
the concentration of Ozone (O
requires that sample and calibration gasses be supplied at ambient atmospheric pressure
in order to establish a stable gas flow through the absorption tube where the gas' ability
to absorb ultraviolet (UV) radiation of a certain wavelength (in this case 254 nm) is
measured.
Calibration of the instrument is performed in software and does not require physical
adjustments to the instrument. During calibration, the microprocessor measures the
current state of the UV Sensor output and various other physical parameters of the
instrument and stores them in memory.
The microprocessor uses these calibration values, the UV absorption measurements made
on the Sample Gas in the absorption tube along with data regarding the current
temperature and pressure of the gas to calculate a final O3 concentration.
This concentration value and the original information from which it was calculated are
stored in the unit's internal data acquisition system (DAS).
6.1

MEASUREMENT METHOD

This Section presents measurement principles and fundamentals for this instrument.
083730400A DCN8130
) in a sample gas drawn through the instrument. It
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Teledyne API – Model T400 O Analyzer
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