When developing new residential areas, it is often costly to build sewer networks that comply with gravity flows. Vacuum drainage pipe is a novel scheme that can replace the traditional sewage drainage system. The sewage collection is transported to the pumping station by vacuum pump, which can use a vacuum collection pipe with a smaller diameter and has climbing capability. The vacuum unit first transmits the sewage of the residential area to the drainage pipe of the system, and then the sewage enters the public sewage network from here. In order to control the equipment, it is necessary to continuously measure the liquid level of the vacuum collection well.