Double High Impedance Online PH Sensor Immersion Mounting

KPH310 Online PH Sensor Signal Output: RS-485 Double High Impedance Differential Amplifier Ip68

1.Application Environment

For environmental water quality monitoring, acid/alkali/salt solution, chemical reaction process, industrial production process, can meet the majority of industrial applications online pH measurement requirements.

2.Feature

• Signal Output: RS-485(Modbus/RTU protocol).
• Convenient to connect to PLC, DCS, Industrial Control Computer, General Controller, paperless recording instrument or touch screen, and other third-party equipment.
• Double high impedance Differential amplifier, strong anti-interference, fast response.
• The patented pH probe, with an internal reference fluid at a pressure of at least 100 kpa (1 bar), oozes extremely slowly from the microporous salt bridge, with a forward exudation lasting more than 20 months. Such a reference system is very stable, electrode life than ordinary industrial electrode times longer.
• Easy to install: submerged installation.
• Ip68, protection level.

3.Technical Specifications

4.Dimensional Drawing

Tips: Q&A

1.What is pH? What is the principle of measurement?

The pH value of the solution is the negative logarithm of the hydrogen ion activity in the solution, which is expressed as:

PH = - lgαH +

Because the value of hydrogen ion activity in an aqueous solution is often very small, it is not convenient for application, so the concept of pH value is used

As a solution acidity, neutral and alkaline indicators. Moreover, the pH value can indicate the strength of the acidity and alkalinity of the solution.

In this way, it is very convenient to apply, and thus:

Neutral solution: [H+]= [OH-] = 1X10^-7

Moles per liter, pH is minus lg[H+] is equal to 7

Acid solution: [H+] > [OH -], [H +] > 10^-7Mol /L, pH < 7, the lower the pH, the more acidic;

Alkaline solution: [H+]<[OH-], [H +] < 10^-7Mol /L, pH >7, the higher the pH, the more basic it is.

Activity is the effective concentration, that is, the portion of the ion that is free to participate in a given reaction - that is, to reach the surface of the electrode sensitive membrane to connect to it

The part of the ion that's touching it. Because of the interaction between ions in a solution, the activity is usually less than the concentration, and this interaction will also be

Blocking the movement of ions reduces the number of ions reaching the electrode membrane.

the measurement of pH electrode is the characteristic of the corresponding relation between the output potential of galvanic cell and the pH value of the solution.

This correspondence can be epresented by Nernst equation:

E = Eo-2.3 RT/F*pH

E = measure the potential

Eo = standard potential

R = the gas constant

T = absolute temperature (K)

F = Faraday constant

RT/F = 2.3 slope

The Nernst equation is a very important relationship in electrochemistry.

When measuring pH, Eo(standard potential) and 2.3RT/F(slope) are obtained by electrode calibration. Then the sample is measured to obtain E (measured potential) and the pH value of the sample is calculated by plugging it into the equation.