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Thermo 450I Thermo Scientific Get Quote



Utilizing pulsed fluorescence technology the Model 450i H2S and SO2 analyzer operates on the principle that H2S can be converted to SO2. As the SO2 molecules absorb ultraviolet (UV) light and become excited at one wavelength, the molecules then decay to a lower energy state emitting UV light at a different wavelength. The pulsing of the U.V. source lamp serves to increase the optical intensity whereby a greater U.V. energy throughput and lower detectable SO2 concentration are realized. Reflective bandpass filters, as compared to commonly used transmission filters, are less subject to photochemical degradation and are more selective in wavelength isolation. This results in both increased detection specificity and long term stability.This state-of-the-art gas analyzer also offers features such as an ethernet port as well as flash memory for increased data storage. Ethernet connectivity provides efficient remote access, allowing the user to download measurement information directly from the instrument without having to be on-site.

Key Features

  • Superior zero stability
  • Stable, lone-life UV source
  • Reflective bandpass filters
  • Temperature stabilization reaction chamber
  • Pulsed excitation and intensity stabilization

Technical Specifications

Preset Ranges 0-0.05, 0.1, 0.2, 0.5, 1, 2, 5, and 10 ppm
Extended Ranges 0-0.5, 1, 2, 5, 10, 20, 50 and 100 ppm
Custom Ranges 0-0.05 to 100 ppm
Zero Noise 1.0 ppb Manual H2S or CS 3.0 ppb Auto (10 second averaging time) 0.5 ppb 1.5 ppb (60 second averaging time) 0.25 ppb 0.75 ppb (300 second av
Lower Detectable Limit 2.0 ppb Manual H2S or CS 6.0 ppb Auto (10 second averaging time) 1.0 ppb 3.0 ppb (60 second averaging time) 0.5 ppb 1.5 ppb (300 second aver
Zero Drift Less than 1 ppb
Span Drift +/-1% Full Scale
Response Time 80 seconds (10 second average time) 110 seconds (60 second average time) 320 seconds (300 second average time)
Precision 1% of reading or 1 ppb (whichever is greater)
Linearity +/-1% full scale
Sample Flow Rate 1.0 liter/min
Converter Efficiency > 80% H2S to SO2. Note: Various other Sulfur compounds can be converted at varying %
Operating Temperature 20°C-30°C
Power Requirements 100 vac, 115 vac, 220-240 vac +/- 10% @ 300W
Outputs Selectable Voltage, RS232/RS485, TCP/IP, 10 Status Relays, and Power Fail Indication (standard). 0-20 or 4-20 mA Isolated Current Outout (op
Inputs 16 Digital Inputs (standard), 8 0-10vdc Analog Inputs (optional)


  US Metric
Dimensions 16.75(W) x 8.62\"(H) x 23\"(D) -


  US Metric
Weight 48 lbs ,21.8 kg\"