Online multi parameter water quality analyzer

PH: The instrument consists of signal measurement, calculation, display, network communication, and panel instructions. The impedance transformation of pH and temperature transmission converts 3H to 59.16mV/pH 25C. The low impedance signal converts NTC into a voltage signal. Dissolved oxygen: The oxygen electrode uses platinum (Pt □ as the cathode, Ag/AgCI as the anode, and the electrolyte is 0.1 M potassium chloride (KCI uses a silicone rubber permeable membrane as the breathable membrane). When measuring, a polarization voltage of OilgS is applied between the anode and cathode. Oxygen is consumed at the cathode through the permeable membrane, and the amount of oxygen passing through the membrane is proportional to the concentration of dissolved oxygen in water. Therefore, the maximum diffusion current between the electrodes is proportional to the concentration of dissolved oxygen in water. The instrument detects this current and converts it into oxygen concentration through calculation. At the same time, the thermistor detects the temperature of the solution and compensates for the temperature of oxygen concentration. Conductivity: Measurement principle: To avoid electrode polarization, the instrument generates a high stability sine wave signal applied to the electrode. The current flowing through the electrode is proportional to the conductivity of the measured solution. The instrument converts the current from a high impedance operational amplifier to a voltage signal, which is amplified by a programmable signal amplifier, phase sensitive detection, and filtering to obtain a potential signal reflecting the conductivity; The microprocessor alternately samples the temperature signal and conductivity signal through switch switching. After calculation and temperature compensation, the measured solution is obtained at 25 ° C? The conductivity value at that time and the temperature value at that time.

Residual chlorine: The instrument consists of signal measurement, calculation, display, communication, and panel instructions. The residual chlorine electrode contains a temperature electrode, and the pH electrode amplifies the sampled signal into a low resistance voltage signal through an instrument amplifier, which is then used for calculation and display of the measured value.

Temperature: The resistance signal is converted into a digital quantity.

Turbidity: The transmittance of transmitted light is proportional to the concentration of suspended matter being measured, and the concentration of turbidity is calculated by measuring the transmittance of transmitted light.

Dissolved oxygen: primary battery method