pH Meters

A pH meter or pH meter is a scientific instrument that measures the activity of the hydrogen ion in aqueous solutions, indicating its degree of acidity or alkalinity expressed as pH. The pH meter measures the difference in electrical potential between a pH electrode and a reference electrode. This difference in electrical potential is related to the acidity or pH of the solution. The pH meter is used in many applications ranging from laboratory experimentation to quality control.

The pH meter is used in all those areas where it is important to detect this value. These areas are laboratories, industrial facilities and swimming pools. Above all, in private pools, located outside, it is necessary to control the pH value. This value indicates how acidic or alkaline the water is. The ideal value of a swimming pool is between 7 and 7.4 pH. Any value that deviates from this optimal value influences the quality of the water. The values that are measured with our pH meter influence the effectiveness of the water disinfection media.

In addition, a pH value that deviates a lot can cause damage to materials and the human body. If the value is too low, it can cause leakage damage or corrosion in metals. If the value is too high it can cause itching in the skin, because it is damaging the protective layer of our skin. You can purchase the pH meter in our

Operation of the pH-meter

Potentiometric pH meters measure the voltage between two electrodes and display the result converted to the corresponding pH value. It consists of a simple electronic amplifier and a pair of electrodes, or alternatively a combination electrode, and some kind of display calibrated in pH units. It usually has a glass electrode and a reference electrode, or a combination electrode. The electrodes, or probes, are inserted into the solution to be tested.

The design of the electrodes is the key part: These are rod structures, usually made of glass, with a bulb containing the sensor at the bottom. The glass electrode for measuring pH has a glass bulb specifically designed to be selective to the concentration of hydrogen ions. In immersion in the solution to be tested, the hydrogen ions in the test solution are exchanged for other positively charged ions in the glass bulb, creating an electrochemical potential through the bulb. The electronic amplifier detects the difference in electrical potential between the two electrodes generated in the measurement and converts the potential difference into pH units.

Types of pH Meters

pH meters range from simple and inexpensive pen-type devices, to complex and expensive laboratory instruments, with computer interfaces and various inputs for indicator and temperature measurements that must be introduced to adjust pH variation. The output can be digital or analog, and the devices can be powered by batteries or rely on line power.

Special meters and probes are available for use in special applications, such as harsh environments and biological microenvironments. There are also holographic pH sensors, which allow the measurement of pH colorimetrically, making use of the variety of pH indicators that are available. Additionally, there are commercially available pH meters based on solid-state electrodes, rather than conventional glass electrodes.

Calibration and Maintenance

Very precise measurements require the pH meter to be calibrated before each measurement. More typically, calibration is performed once a day of operation. Calibration is necessary because the glass electrode does not provide reproducible electrostatic potentials for extended periods of use times.

Calibration is performed with at least two standard buffer solutions that cover the range of pH values to be measured. For general purposes, buffers at pH 4.00 and pH 10.00 are appropriate. The pH meter has a calibration control to set the meter reading equal to the value of the first standard damper and a second control that is used to adjust the meter reading to the value of the second damper. A third control allows you to adjust the temperature. More accurate measurements sometimes require calibration to three different pH values.

Good laboratory practice dictates that after each measurement the probes are rinsed with distilled water to remove any trace of the solution being measured, cleaned to absorb the remaining water that could dilute the sample and thus alter the reading.