Industrial online acid-base concentration meterBy adopting high-precision AD conversion and single-chip microcomputer processing technology, it can complete various functions such as acid and alkali concentration measurement, temperature measurement, automatic temperature compensation, automatic range conversion, and instrument self-test.
Industrial online acid-base concentration meterThe concentration of a solution is indirectly measured by measuring its conductivity. It is known that at a constant temperature, the conductivity of a low concentration electrolyte corresponds to the concentration of the solution. When the concentration remains constant and the temperature of the solution changes, the conductivity also changes, that is, the concentration of the solution is a function of conductivity and temperature. If the temperature of the solution can be measured and corrected to the conductivity at standard temperature according to the corresponding relationship mentioned above, it can be directly converted to the concentration of the solution. It should be emphasized that the concentration of the solution is the sum of the conductivity of all conductive ions in water. If there are two or more conductive combination components in water, the above concentration temperature conductivity data can be measured, and this instrument can also be used for measurement; If the ratio of conductive components in water is uncertain, this instrument cannot be used for measurement.
To avoid electrode polarization, the instrument generates a highly stable square wave signal that is applied to the conductivity cell. The current flowing through the conductivity cell is proportional to the concentration of the measured solution. The secondary meter converts the current from a high impedance operational amplifier to a voltage, which is amplified, detected, and filtered by a programmable signal to obtain a potential signal reflecting the concentration; The microprocessor alternately samples the temperature signal and conductivity signal, and after calculation and temperature compensation, obtains the concentration value at a constant temperature.
The temperature coefficient setting range is 0-10% ℃ -1. The temperature coefficient for measuring HCL concentration is set to 1.60% at the factory, and the temperature coefficient for measuring NaOH concentration is set to 1.90% at the factory. Users are advised not to make any modifications.
When "Automatic" is selected in the "Temperature Measurement" project and the temperature compensation electrode is connected, the temperature value displayed in this table is the measured value of the temperature compensation electrode, and the instrument will perform automatic temperature compensation. When "Manual" is selected in the "Temperature Measurement" project, the instrument is in the manual temperature setting state, which does not detect the actual temperature of the measured liquid, but uses and displays the temperature value manually set by the user. There will be a "Hand" character in front of the temperature value on the display screen, and the instrument performs manual temperature compensation.