Principles Of Operation; Measurement Principle; H S Conversion - Teledyne T101 Operation Manual

Teledyne ML - T101 Operation Manual

10. PRINCIPLES OF OPERATION

10.1. MEASUREMENT PRINCIPLE

10.1.1. H S CONVERSION
2
The T101 UV Fluorescence H
determines the concentration of hydrogen sulfide (H
the instrument It requires that sample and calibration gases be supplied at ambient
atmospheric pressure in order to establish a constant gas flow through the sample
chamber where the H S in the sample gas is converted into SO
2
to ultraviolet light causing the SO
these SO * molecules decay back into SO
2
amount of fluorescence to determine the amount of SO
chamber and by inference therefore the amount of H
Calibration of the instrument is performed in software and usually does not require
physical adjustments to the instrument. During calibration, the microprocessor measures
the sensor output signal when gases with known amounts of H
concentrations are supplied and stores these measurements in memory. The
microprocessor uses these calibration values along with other performance parameters
such as the PMT dark offset, UV lamp ratio and the amount of stray light present and
measurements of the temperature and pressure of the sample gas to compute the final
H S concentration.
2
This concentration value and the original information from which it was calculated are
stored in the unit's internal data acquisition system and reported to the user through a
vacuum fluorescent display or as electronic data via several communication ports.
This concentration value and the original information from which it was calculated are
stored in the unit's internal data acquisition system (DAS Section 4.8) and reported to
the user through a vacuum fluorescent display or several communication ports.
The T101 H S analyzer is basically a SO
2
inserted into the gas stream before the sample gas enters the sample chamber.
The H S to SO converter receives sample gas from which the SO
2 2
by a scrubber. Once the naturally occurring SO
special converter changes the H
catalytic oxidation.
S Analyzer is a microprocessor controlled analyzer that
2
S), in a sample gas drawn through
2
molecules to change to an excited state (SO
2
, they fluoresce. The instrument measures the
2
S present in the sample gas.
2
analyzer with a H
2
is removed from the sample gas, the
2
S in the sample stream to SO
2
Principles Of Operation
which is then exposed
2
*). As
2
is present in the sample
2
S at various
2
S  SO
conversion stage
2 2
has been removed
2
using a high-temperature
2
245