describe

1.Structural characteristics: The whole measurement system is mainly composed of two parts: instrument (secondary table) and dissolved oxygen electrode (primary table). The dissolved oxygen electrode contacts the measured solution, and the instrument shows the oxygen content, temperature and working state of the aqueous solution. 2.Working principle: the oxygen electrode is made of platinum (Pt) cathode, Ag / AgCl as the anode, the electrolyte is 0.1M potassium chloride (KCl), and the silicone rubber permeable membrane is used as the breathable membrane. When measuring, a polarization voltage of 0.68V is added between the anode and cathode, oxygen is consumed at the cathode through the permeable membrane, and the amount of oxygen through the membrane is proportional to the concentration of dissolved oxygen in the water, so the limiting diffusion current between the electrodes is proportional to the concentration of dissolved oxygen in the water. The meter detects this current and transforms the oxygen concentration by calculation. Meanwhile, the thermistor detects the temperature of the solution and temperature compensates for the oxygen concentration.