The Digox optical is an in-line measuring device for dissolved oxygen, based on the optical procedure of the dynamic fluorescence quenching. The device uses neither a membrane nor an electrolyte. The measurement is independent of the CO2 content and the flow of the medium. The Digox optical has a simple and compact design as a unit of measuring device and process adapter (VARIVENT®), therefore, no wall mounting is necessary. The system is able to support 130 °C (CIP). A sensor replacement (pre-calibrated in the factory), which is required every 1 to 2 years, can be carried out simply and quickly, directly at the line, without dismantling the device.
The menu guidance system in the device software is intuitive and supported through pictograms. Various unit statuses are displayed using different colours in the display illumination. The measuring values can be shown graphically with a trend display. Intelligent diagnosis functions inform the user about the sensor´s wear by the respective process conditions.
The Digox optical is calibrated using the portable Digox 6.1 as reference measuring device without removing the sensor; depending on process conditions, the calibration data may be automatically corrected. The measuring range of the new system is 2 mg/l (version LOW) and 45 mg/l (version HIGH). A short response time (t90 < 39 s) and a high measuring accuracy of +/- 1 ppb guarantee a precise and reliable oxygen measurement in the production process.
For connection with a superordinated process control system, the Digox optical has 2 analog outputs, 3 programmable switching outputs, 2 configurable digital inputs as well as an optionally usable Profibus DP.
This system can be used in many areas of the brewery for measuring tasks and process control: water degassing, wort aeration, yeast propagation, fermenting cellar, filtration, at separators, filling and CO2 recovery. It is eminently suitable for the integration in brewing plants.