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precisive tfs tunable filter spectrometer
Optical Gas Analyzer, Tunable Filter Spectroscopy, Acid and Sour Gas


  • Measurement Technique
    Tunable Filter Spectroscopy
  • Measurement Channels
    H2S, CH4, C2H6, C3H8, i-C4H10, n-C4H10, C5H12, CO2, optional NH3 and/or H20, BTU Calorific/heating value, Wobbe index
  • Measurement Ranges
    Methane: 0 - 100% (C1)
    Ethane: 0 - 25% (C2)
    Propane: 0 - 25% (C3)
    iso-Butane: 0 - 10% (iC4)
    n-Butane + n-Pentane: 0 - 10% (nC4 + nC5)
    iso-Pentane + neo-Pentane: 0 - 10% (iC5 + neoC5)
    n-Hexane: 0 - 5% (nC6)
    Carbon Dioxide: 0 - 50% (CO2)
    Hydrogen Sulfide: 0 - 50% (H2S)
    Calculated balance (N2, O2, H2) or analog inputs for H2 and/or O2
    Calorific Value (CV) and Wobbe Index (WI) per ISO 6976:1995
  • Repeatability
    Hydrocarbon, H2S and CO2 channels: < ± 0.05% (absolute)
    CV and WI computation: < ± 0.05% (relative of reading)
  • Zero Drift
    Not to exceed 0.2% per month on each hydrocarbon channel Maximum of 0.5% throughout life of bulb (~ 18 months) if not re-zeroed
  • Sample Pressure
    0.1 - 5 psig
  • Flow Rate
    0.1 - 2 L/min
  • Update rate
    5 seconds (default), software selectable from 1 - 120 seconds
  • Certifications
    CSA Class 1Div2, Groups A/B/C/D,T4. ATEx Zone 2, Ex nAnCIICT4Gc


Precisive TFS™ Light Absorption Spectroscopy Schematic

Simplified schematic of light absorption spectroscopy

The Precisive TFS™ (Tunable Filter Spectrometer) sensor platform consists of a light source, a sample cell (for gases, liquids or solids), a wavelength separating element (spectrometer) and a photo-detector. The wavelength separating element "slices" the wavelength components of the broadband light source which then interacts with the sample molecules. Some of the wavelength components are absorbed and some are transmitted through without any absorption.

Advanced Spectral Decomposition Algorithm

Light absorption spectroscopy with advanced spectral decomposition algorithm

Precisive TFS™ Tunable Filter Spectrometers use an advanced spectral decomposition algorithm. The resulting spectrum is called absorption spectrum, which acts as "fingerprints" which are used to identify the sample components and/or quantify the composition of the sample.

Precisive® 5-253 Benefits

  • A single all-optical analyzer for C1-C6 hydrocarbons, H2S plus hydrocarbon and CO2 measurement: Complete feed stream analysis with a maintenance-free analyzer that requires no carrier gas.
  • Analysis in seconds: Continuous measurement instead of batch handling with minimized sampling.
  • Speciation by Tunable Filter Spectroscopy (TFS™) technology: Full C1 through C6 hydrocarbon speciation with virtually no cross-interferences. Optional NH3 and H2O measurement for an 11-channel analysis with a single all-optical analyzer.
  • Flow-through sensor design: No sensitivity to pressure and flow variations with light source and detector stability proven in hostile
    applications from drill sites to "sooty" refineries.
  • Compact, outdoor-rated, low-power: Well suited for fixed and transportable applications with a NEMA4X, IP66 rated enclosure.

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