Yokogawa In-Situ Gas Analyzer TDLS200 - Manual (Page 79)

6-22 6-23
IM 11Y01B01-01E-A 6th Edition :Feb 13, 2013-00
<6. BASIC OPERATION>
Following pages are the various “Laser Spectra & Control” screen captures that depict the different scenarios
depending on what process gas(es) are present in the OPL and what gas is purged through the analyzer:
Note that the actual magnitude of the absorption units (au) as indicated on the “Absorption Spectrum” Y-Scale
(vertical) will vary depending upon the actual gas concentrations, optical path lengths, gas temperatures and gas
pressures.
TDLS200 TDL Analyzer Instruction Manual V2.1
Page 73 of 131 - 3 7 -
Following pages are the various “Laser Spectra & Control” screen captures that depict the different
scenarios depending on what process gas(es) are present in the OPL and what gas is purged
through the analyzer:
Note that the actual magnitude of the absorption units (au) as indicated on the “Absorption
Spectrum” Y-Scale (vertical) will vary depending upon the actual gas concentrations, optical path
lengths, gas temperatures and gas pressures.
Off-Line Calibration Conditions:
Process/Calibration OPL: N
2
Analyzer Purge: N
2
This is how the absorption spectra will appear when
there is neither measured or reference gas (i.e.NH
3
and H
2
O) in the entire optical path (Process OPL
and Analyzer Purge).
required for an Off-Line Zero
Calibration of the analyzer.
Process/Calibration OPL: ~20 ppm NH
3
Analyzer Purge: N
2
In this Absorption Spectra view, there is practically
zero reference gas (H
2
O) absorption peak in the
approximate peak center position (PCP) 167 region.
There is approximate 20 ppm of me a s ured gas
(NH
3
) (@ approx PCP ~120) absorption in this
spectra based on 72.6cm OPL, ambient
temperature and ambient pressure.
required for an Off-Line Span
Calibration of the analyzer.
This is the spectra appearance
This is the spectra appearance
Process/Calibration OPL: N2
Analyzer Purge: N2
This is how the absorption spectra will appear
when there is neither NH
3
nor H
2
O in the entire
optical path (Process OPL and Analyzer Purge).
This is the spectra appearance
required for an Off-Line Zero
Calibration of the analyzer.
Process/Calibration OPL: ~20ppm NH
3
Analyzer Purge: N
2
In this Absorption Spectra view, there is practi-
cally zero H
2
O absorption peak in the approxi-
mate peak center position (PCP) 167 region.
There is approximate 20 ppm NH
3
(@ approx
PCP ~120) absorption in this spectra based on
72.6cm OPL, ambient temperature and ambient
pressure.
This is the spectra appearance
required for an Off-Line Span
Calibration of the analyzer.