Principle of oxygen controller

The oxygen controller is composed of polarographic diaphragm oxygen electrode as sensor, advanced medium and large scale integrated circuit and 3. 5 led high brightness digital display. It has preset upper and lower limit digital dials and gives an alarm through sound and light. Input upper and lower limit control contacts; 0- 10 mA or 4-20 mA output, automatic zero stabilization and other functions can make the oxygen content of the controlled system within a given range. The oxygen electrode produced by our factory has obtained a patent in China: after using this patent, the stability, sulfur resistance and hydrogen resistance of the instrument have been greatly improved compared with the original instrument.

Working principle: The instrument consists of oxygen electrode, amplifier, analog comparator and alarm. Oxygen electrode: polarographic diaphragm type, with platinum as cathode, silver chloride as anode, and polytetrafluoroethylene as permeation isolation membrane. The oxygen in the gas sample can reach the cathode through the membrane, and the following reaction occurs under the polarization voltage of 650mV. Cathode: O2 2H204E 4OH Anode: Ag·CL·AgCL reaction can quickly reach equilibrium, and at the same time, it produces a limiting diffusion current, which is proportional to the partial pressure of oxygen in the gas sample. This current is amplified by the amplifier and drives the display screen to display the oxygen content in the gas sample. At the same time, the current of 0- 100 mA is output for external recorder to record, and the data can be archived. The other path is compared with the comparator to push the relay. When the oxygen content exceeds the set value, the instrument gives an audible and visual alarm and controls the output of the upper limit control contact.