The installation location of the pH electrode must be selected in the area where the medium is active. It cannot be set in the dead zone. If it is installed in a circulation pool, it must be ensured that the meduim in the pipeline is flowing, otherwise it cannot reflect the real-time pH value, and the online pH analyzer loses its meaning.

The installation of pH electrodes can be roughly divided into three types: flow cell installation, insertion installation, and immersion installation.

Flow Cell Installation

The installation of the circulation flow cell means that the medium is introduced into the flow cell, and the pH electrode is inserted into the flow cell for measurement. The medium can enter the flow cell through a sampling pump. However, it should be noted that if the medium operating pressure is too high or the operating temperature is too high, it must be pre-treated first, and the temperature and pressure must be reduced to meet the electrode’s adaptability before the medium can be introduced into the flow cell. pH electrodes from different manufacturers have different pressure and temperature resistance capabilities. Usually, the pressure resistance limit is about 6 bar, and the temperature resistance limit is about 80℃. Try not to approach the limit when using it. Although the pH value can be effectively measured under this condition, the life span will be affected.

Immersion Installation

When measuring the pH of the medium in the pool and the pH Probe is allowed to be inserted into the pool, the immersion installation is preferred. In this method, it is necessary to pay attention to the pH electrode always being immersed in the liquid surface of the medium. The pH electrode will become ineffective if exposed to the air for a long time.? The pool is usually outdoors. This installation method does not need to lead the medium out, so there is no need to consider the problem of winter heating. The detection is very intuitive and the installation is also very convenient. However, if the working conditions do not allow the pH probe to be inserted into the pool, the circulation flow cell installation method can only be used. The medium is pumped into the flow cell with a sampling pump, and the medium is discharged into the pool after analysis.

Insertion installation

Insertion installation means that the pH electrode is directly inserted into the pipeline or equipment for measurement without using a flow cell. The pH electrode and the equipment or pipeline are connected by threads or flanges. This pipeline installation method is not recommended because the pH electrode needs regular maintenance and is a consumable item. Its life is not as long as that of thermometers, flow meters and other instruments. This direct insertion method can usually only remove the pH electrode for cleaning or replacement when the device stops monitoring. It can not be maintained in the middle. When the medium flow rate is too fast, the electrode is constantly flushed, which will reduce the service life of the electrode. If it breaks in the middle, it cannot be replaced, and the pH value cannot be monitored online.

Therefore, when the online pH analyzer measures the pH of the medium in the equipment or pipeline, the flow cell method is recommended first, and the stop value is installed on the pipeline in and out of the flow cell to facilitate maintenance and replacement. When the online analyzer measures the pH of the medium in the water pool, the immersion type is recommended first, without considering heating and drainage. In the face of different complex working conditions, different pH electrode installation methods need to be selected.