Thermo Scientific SOLA II Flare, Руководство пользователя

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Chapter 1
Product Overview
Thermo Scientific SOLA II Flare User Manual 1-5
Validation
The validation function can be performed with a preset time in the software or
on demand. This function is a programmed sequence and once activated the
SOLA II Flare will complete the sequence and report the data for the
validation. To meet the daily reporting requirements, the validation should be
done on a timed basis controlled by a third-party PLC. The on-demand
function, which can be activated via the front panel or the PLC, should be used
to determine if there is a problem with the analyzer system. For further
information, see
Validation .
Calibration
Calibration should be performed after a validation failure. For further
information, see
Calibration .
Principle of
Operation
The detector is based on the principle that SO
2
molecules absorb UV light and
become excited at one wavelength, then decay to a lower energy state and emit
UV light at a different wavelength. Specifically,
The sample in and sample out are routed into the oven through a heat traced
line. The traced bundle enters through a hole in the oven and a heat shrinking
boot, typically provided by the system integrator. The sample is mixed with air
and passes through a pyrolyzer furnace that oxidizes the sulfur molecules in the
sample to produce SO
2
. The sample then flows into the fluorescence chamber,
where pulsating UV light excites the SO
2
molecules. The condensing lens
focuses the pulsating UV light onto a mirror assembly. The mirror assembly
contains four selective mirrors that reflect only the wavelengths that excite SO
2
molecules.
As the excited SO
2
molecules decay to lower energy states, they emit UV light
that is proportional to the total sulfur concentration in the sample. The
bandpass filter allows only the wavelengths emitted by the excited SO
2
molecules to reach the PMT, which detects the UV light emission. The photo
detector, located at the back of the fluorescence chamber, continuously
monitors the pulsating UV light source to provide compensation for
fluctuations. The measured SO
2
concentration, representing the total sulfur in
the sample, is processed, displayed on the front panel display, and sent to the
analog outputs.