EXcell 231

NIR Biomass Sensor Ø12mm

EXcell 231 is a high-precision digital NIR absorption sensor for monitoring production processes in the biotech, food and pharmaceutical industries. Its 12mm stainless steel design and wear-free sapphire windows make the EXcell 231 a reliable and intelligent sensor with integrated digital amplifier. Various measuring units for absorbance, turbidity and mass such as EBC / FAU / mg / l / AU / OD or customer-specific units can be output. With the associated EXpert software, the sensor can be conveniently parameterized on the PC and the measurement data can be recorded and graphically displayed. A Modbus RS485 interface and an interface for a 0-20mA output with integrated measured value display are also available.

The sensor is attached to the process via a PG13.5 thread. The installation dimensions on the process side correspond to a standardized pH sensor. The EXcell 231 sensor can therefore also be used in conjunction with probe housings and fully automatic cleaning systems.

In combination with our proven EXtract 8XX series retractable probe housings and the associated EXmatic 470/471 control unit (fully automatic), automatic cleaning is also possible under process conditions and thus offers safe use even in the most difficult applications.


Your advantages

  • EBC / FAU / mg/l / AU / OD or customer defined units
  • Standardized 12 mm design with integrated amplifier
  • No traditional transmitter necessary
  • Wearless sapphire windows, CIP/SIP-capable
  • Hygienic design, autoclavable
  • Maintenance free due to LED light source
  • Data output directly on PC, Modbus RS485 or 0...20 mA
  • Easy parametrization with EXpert software
  • Usable with retractable housings for automated sensor cleaning


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Measuring range: 0...6 AU, 0...6600 EBC
Resolution: 0,01 AU
Accuracy: ± 1 %
Reproducibility: ≤ 1 % from final value
Wave length: 850 nm
Light source: LED
Optical path length: 5 / 10 / 20 mm
Shaft length (mm): 120 / 225 / 325 / 425
Wetted material: stainless steel 1.4435 (316L)
Surface: Ra <0.37 µm
Measuring window: sapphire
Process connection: thread PG13,5
Process temperature: 0...90 °C, 135 °C max. 1 hour (SIP cycle)
Process pressure: max. 16bar (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 small fermentation reactors
  • Cell growth measurement
  • Filter observation
  • Color independent concentration measurement

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