ENDRESS+HAUSER  OUSAF44-B0A0

Optical sensor combined with the OUA260 flow assembly for the measurement of UV absorption

The sensor measures the spectral absorption of process liquids in the ultraviolet region of the electromagnetic spectrum.

• Measurement of protein concentrations
• Chromatography monitoring
• Filtration monitoring
• Concentration measurement of organic compounds
• Detection of aromates

• Improved process control and easier quality control thanks to quick and reliable monitoring of product concentration
  • Measuring range up to 2.5 AU or 50 OD (depending on optical path length)
  • Measurement of UV absorption at discrete wavelengths between 254 nm and 365 nm
  • Outstanding filter properties for highest linearity
  • Direct concurrence with laboratory values
  • Integrated reference detector for lamp compensation
  • Gas discharge lamp for long service life and stable measured values
  • Patented Easycal system (optional)
    • Cost-effective, time-efficient calibration
    • Easy, in-line calibration which is traceable to NIST without any liquid standards
    • FM- and ATEX-approved lamps for applications in the hazardous area
    • Compliance with life sciences sector thanks to hygienic design and FDA- and USP-compliant sealing materials
    • High degree of product safety as SIP/CIP-resistant
    • High product yield thanks to low volume requirements
    • Maximum durability in all applications owing to wide range of materials and process connections
    • Can be adapted to process requirements:
      • Optional air purge ports to prevent the formation of condensate on the optical windows
      • Optional adjuster for optical path length
      Measuring principle

      The measuring principle is based on the Lambert-Beer law.

      There is a linear dependency between the absorption of light and the concentration of the absorbing substance:

      A = -logA m = ε . c . OPL
      A ... absorption, A m ... absorption measured by detector
      ε ... Extinction coefficient
      c ... Concentration
      OPL ... Optical path length

      A light source emits radiation through the medium and the incident radiation is measured on the detector side.

      Once the light has passed through a filter for wavelength selection, the intensity of the light is determined by a photodiode and converted to a photocurrent.

      The subsequent conversion to transmission (%) or absorbance units (AU, OD) is performed in the associated transmitter.