Integral to process control in many industries, level measurement sensors fall into two main types. Point level measurement sensors are used to mark a single discrete liquid height-a preset level condition. Generally, this type of sensor funetions as a high alarm, signalling an overfill condition,or as a marker for a low alarm condition. Continuous level sensors are more sophisticated and can provide level monitoring of 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 to a visual indicator.