The level meters used in power plants are basically radar, radio frequency admittance or acoustic. The head of the liquid level gauge is exposed outside the ash hopper, and the head is wired, and the measuring part is inserted into the ash hopper. Material level meter in electrostatic precipitator hopper. As you know, the environment inside is easily covered by ash or blocked on the components at the measuring end of the level gauge. In this case, the level gauge will be mistaken for a high level. In fact, all the level meters in power plants have such problems, and basically there are often false positives. According to the technical staff of the liquid level gauge manufacturer who came to the site to consult me, there is basically no perfect solution, and generally it is to adjust the sensitivity of the liquid level gauge or knock off the dust hanging inside. I hope it helps you.