How a pH Sensor Works

what is a ph sensor?

Digital pH sensor use compound electrode technology. The sensor has a built-in temperature sensor that automatically compensates for temperature. The alloy electrode has a longer life and is suitable for online long-term monitoring environments.

How a pH Sensor Works

The working principle of the PH sensor is that the hydrogen ion glass electrode and the reference electrode form a primary cell. During the ion exchange process between the glass membrane and the hydrogen ions in the measured solution, the potential difference between the electrodes is measured to detect the hydrogen ions in the solution. concentration, thus measuring the pH value of the liquid being tested.

PH sensor is commonly known as PH probe, which consists of two parts: glass electrode and reference electrode. The glass electrode consists of a glass support rod, a glass membrane, an internal reference solution, an internal reference electrode, an electrode cap, and wires. The reference electrode has a known and constant electrode potential, usually a calomel electrode or a silver/silver chloride electrode. Since the pH value is related to temperature, a temperature electrode is generally added for temperature compensation to form a three-pole composite electrode.

The acidity meter is an instrument for measuring the pH value of a solution. The main body of the acidity meter is a precise potentiometer. During the measurement, the composite electrode is inserted into the measured solution, and different electromotive forces are generated due to the different acidity (hydrogen ion concentration) of the measured solution. Amplify it through the DC amplifier, and then indicate the pH value of the measured solution by the reading indicator (voltmeter). Widely used in industry, agriculture, scientific research, environmental protection and other fields. The instrument is also a necessary inspection equipment for food factories and drinking water factories to do QS and PHCCP certification.

PH sensor function

1. Process technology and monitoring.
2. Papermaking.
3. Plastic chemical industry.
4. Calcining plant.
5. Water treatment, sewage, cooling water.

The pH sensor can also measure pH value in large reaction tanks or process pipelines; high temperature sterilization, CIP cleaning; electrode lengths are 120, 150, 220, 250, 450 mm and other options.

When in use, the pH sensor is usually covered with a stainless steel protective sleeve before being inserted into the fermenter. Most pH sensors have a temperature compensation system. Since electrode contents will change with time of use or autoclaving, calibration is required before each batch of fermentation sterilization, i.e. with a standard pH buffer. Usually the pH sensor has a measurement range of 0 to 14, an accuracy of ±(0.05 to 0.1), a response time of several seconds to tens of seconds, and a sensitivity of 0.1.

Leave a Comment

Your email address will not be published. Required fields are marked *