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.