EXcell 241

NIR Biomass Sensor DN25

EXcell 241 is a high-precision digital NIR absorption sensor for DN25 weld-in sockets for monitoring biomass measurement in biotech, food and pharmaceutical applications. Its stainless steel design, standard DN25 weld-in socket and wear-free sapphire windows, LED technology and integrated digital amplifier make it a reliable, robust, cost-efficient and unique measuring device for typical industrial fermentation vessels, whereby different measuring units for absorbance, turbidity and mass such as AU / OD / FAU / EBC or mg/l can be displayed or even a customized measuring unit can be selected.

The EXpert parameterization software enables convenient and simple sensor parameterization. Measured values can also be displayed graphically and can be saved and exported. Various communication interfaces are available for USB, RS485 Modbus or for 0...20mA current output.

The sensor is attached to the weld-in socket via a G1 1/4" thread, whereby the O-ring position can be freely selected according to the existing socket to enable the best possible sterile installation.


Your advantages

  • EBC / FAU / mg/l / AU / OD or customer defined units
  • Design for DN 25 weld-in sockets
  • With integrated amplifier
  • No traditional transmitter necessary
  • Wearless sapphire windows, CIP/SIP-capable
  • Hygienic design, autoclavable
  • Maintenance free due to LED light source
  • PC-connection via USB, Modbus RS485 or 0…20 mA current output interfaces
  • Easy parametrization via EXpert software


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Measuring range: 0...6 AU, 0...6600 EBC
Resolution: 0,1 % or 0,01 AU
Accuracy: ± 1 %
Reproducibility: ≤ 1 % from final value
Wave length: 850 nm
Light source: LED
Optical path length: 5 / 10 / 20 mm
Immersion length: 70-85 mm / 110-125 mm
Wetted material: stainless steel 1.4435 (316L)
Surface: Ra <0.37 µm
Measuring window: sapphire
Process connection: thread G1 1/4
Process temperature: 0...90 °C, 135 °C max. 1 hour (SIP cycle)
Process pressure: max. 16 bar (232psi)
Electrical coonection: Fischer Core Series
Cable length: 2 m / 5 m
Interfaces: USB, RS485 Modbus, 4...20 mA
Protection class: IP68



  • High accurate OD measurements up to 12 OD
  • Suitable for fermentation processes
  • Usable in industrial fermentation vessels
  • Cell growth measurement
  • Filter observation
  • Color independent concentration measurement

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