Superior technology
The Transmitter ZD22 is specifically designed for long-term monitoring of oxygen concentrations. The integrated amperometric oxygen sensor is based on an electrochemical oxygen pumping cell made of zirconium dioxide. It is characterized by its robustness, a very high life expectancy and its outstanding long-term stability. The integrated thermostatic control of the sensor element achieves accurate measuring results in the entire temperature range, regardless of the operating temperature. The sensor selectively detects the oxygen and is sensitive to many sensor poisons known at the electrochemical sensors. It can be also permanently used in environment with high concentrations of CO2 or in dry atmosphere. A special equipment is available to protect the transmitter when used in very difficult.
Principle of operation
The electrolytic cell consists of a zirconium dioxide-based ceramic (ZrO2), coated on both sides with porous platinum electrodes. The platinum reduces the gaseous oxygen O2 to O2 ions. By applying a voltage to the two platinum electrodes, a ion based current is created in the oxygen ion conductive ZrO. The necessary high temperature of the ceramics is generated a in the heating element integrated in the sensor. The gas diffusion current is limited by a cap with integrated capillary, so that all its diffused oxygen molecules are ionized. This diffusion current generates a signal proportional to the oxygen concentration signal.