As the name suggests, the suspended solids analyzer is an online analysis instrument designed to measure the concentration of suspended solids in the process of municipal sewage or industrial wastewater treatment. Suspended solids (SS) in water are particles with a particle diameter of about 0.1um or more, which are usually visible to the naked eye. These suspended particles are mainly composed of silt, soil, protozoa, algae, bacteria, viruses, and high-molecular organic matter. They are often suspended in the water flow. These suspended particles can make the water turbid. There are many methods to measure suspended solids in water. Currently, the commonly used method is to use a suspended solids analyzer. This detector has the characteristics of simple measurement process, short measurement time, and accurate measurement results. It is suitable for various enterprises, institutions, scientific research institutions, and universities. Detection, monitoring, testing, etc. of suspended solids in water. The suspended solids analyzer is composed of a transmitter and a sensor. The sensor can be easily installed in the pool, drainage pipe, pressure pipe or natural water body. The analyzer can automatically compensate for the interference caused by pollution. Two-way digital communication between transmitter and sensor prevents signal degradation and allows sensors to be located at greater distances between transmitters. The sensor has an air cleaning function, which can be cleaned automatically and regularly according to the preset time, thus greatly reducing the workload of instrument maintenance. Whether evaluating activated sludge and the entire biological treatment process, analyzing wastewater discharged after purification treatment, or detecting the sludge concentration at different stages, it can give continuous and accurate measurement results. The attenuation of infrared light transmitted and scattered in sludge and suspended solids is related to the concentration of suspended solids in the liquid. The infrared light sent by the transmitter on the sensor is absorbed, reflected and scattered by the measured object during transmission, and only a small part of the light can be irradiated on the detector. The transmittance of the transmitted light has a certain relationship with the concentration of the measured sewage , so the concentration of sewage can be calculated by measuring the transmittance of transmitted light. The four-beam technology uses two emitters and two detectors. The light sent by each emitter is transmitted and then irradiated on the two detectors, so that a series of optical paths are generated to obtain a data matrix, and then by analyzing these Data signal, the suspended solids analyzer can get the accurate concentration of suspended solids in the medium, and can effectively eliminate interference, compensate for the deviation caused by pollution, so that the instrument can work in a harsh environment.