Dissolved Oxygen Sensor

Published on: 
Pharmaceutical Technology, Pharmaceutical Technology-03-02-2018, Volume 42, Issue 3
Pages: 12

Endress+Hauser's Memosens COS81D hygienic optical sensor can measure dissolved oxygen in pharmaceutical fermenters and bioreactors.

Endress+Hauser’s Memosens COS81D hygienic optical sensor can measure dissolved oxygen in pharmaceutical fermenters and bioreactors. The device can be used in all measuring points ranging from lab fermenters to production processes and has measurement capabilities that also include gaseous oxygen and temperature with accuracy up to ±0.2%, in addition to temperature, partial pressure, and raw measured values, according to the company.

The sensor is suitable for cleaning-in-place (CIP) and sterilizing-in-place (SIP) procedures and works in process temperatures from 15-280 °F and pressures ranging from 0-190 psi. The device also has a low sampling volume, making it suitable for residual oxygen measurement in water treatment and boiler feedwater. The sensor has a compact stainless steel 12mm design with lengths currently up to 220 mm.

The device connects to a transmitter via a cable that transmits an optical digital signal, which is continuously monitored and analyzed. The transmitter senses unusually high or low measured values, irregular values caused by incorrect measured values, and aging of the sensor cap. When errors are detected, the transmitter displays a warning and produces an error message.

Measured and calibration values in the sensor are sent to the transmitter using a non-contact connection that has reduced potential interference, according to the company. Memosens technology in the transmitter generates an automatic error message if the sensor fails, or if the connection between sensor and transmitter is interrupted.

Additionally, the sensor has integrated electronics that store calibration data and other information, such as total hours of operation and operating hours under extreme measuring conditions. Calibration data are stored in the sensor, enabling the device to be calibrated and adjusted independent of the measuring point.

Endress+Hauser