Point level sensors are used to mark a height of a liquid at a certain preset level. Generally, this type of sensor works as an alarm, indicating an overfill when the determined level has been reached, or on the contrary, a low level alarm.
Continuous level sensors are more sophisticated and can monitor the level of an entire system. These measure the level within a specified range, rather than at a single point, producing an analog output that directly correlates to the level in the vessel. To create a level management system, the output signal is linked to a process control loop and a visual indicator.