interrupteur à diaphragme

CONT: The diaphragm switch is a popular type for professionals and is also the most expensive. The entire sump pump is immersed under water and on it is a membrane that is sensitive to water pressure. As the water level rises, the water pressure increases and the diaphragm becomes concave, thereby activating the switch to turn on the sump pump. Whe the water level drops, the switch turns off.
OBS: A diaphragm switch can [also] be used to eliminate bin overflow, maintain a predetermined material level, indicate plugging of chutes or conveyors or provide any of a number of level control functions.