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precisive tfs tunable filter spectrometer
Optical Gas Analyzer, Tunable Filter Spectroscopy, Olefins


  • Measurement Technique
    Tunable Filter Spectroscopy
  • Measurement Channels
    CH4, C2H6, C2H4, C3H8, C3H6, i-C4H10, n-C4H10, up to 20 alkanes, alkynes, alkenes, CO, CO2, H2S and analog inputs including H2 and O2
  • Measurement Ranges
    Ethylene: 0 - 100%
    Propylene: 0 - 100%
    Acetylene: 0 - 30%
    i-Butene: 0 - 20%
    1-Butene: 0 - 20%
    Cis-2-Butene: 0 - 20%
    t-Butene: 0 - 20%
    Methane: 0 - 100%
    Ethane: 0 - 25%
    Propane: 0 - 25%
    iso-Butane: 0 - 50%
    n-Butane: 0 - 50%
    i-Pentane: 0 - 10%
    balance channel reported (H2, N2, O2, CO2)
    BTU Calorific Value (CV) and Wobbe Index (WI) per ISO 6976:1995
  • Repeatability
    Better than 0.1% (typically 0.05%)
  • Accuracy
    1% (absolute) or 0.2% FS (greater of)
  • Zero Drift
    Not to exceed 0.2% per month on each hydrocarbon channel
  • Sample Pressure
    0.1 - 2 psig
  • Flow Rate
    0.1 - 1 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, IECEx


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® 5-154 Benefits

  • Analysis in seconds: Continuous measurement instead of batch handling with real-time feedback.
  • Simple to install and maintain: No carrier gas or instrument fuel gas required for low operational costs.
  • Linear across measurement range: Linear response across the full measurement scale.
  • Precision and accuracy: Accurate and reproducible results in under 5 seconds for combustion control to a PLC.
  • Flow-through sensor design: No sensitivity to pressure and flow variations minimizes potential sampling issues.
  • Small footprint, outdoor rated: Extractive process mounted - replace GC installation with process control to DCS via real-time Modbus output, and a NEMA 4X, CSA Class1Div2, ATEX Zone2, IP66 rated enclosure.

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