Level measurement is one of the most important variables in process automation. Measuring level can be used for: ensuring safety, maximizing use of raw materials; controlling inventories and product manufacturing, ensuring quality and repeatable production; legal trade operations; tracking production totals; and much more. And out of the millions of level measurement devices in applications from heavy industries like mining and cement to sensitive pharmaceutical environments, there are three major categories of device types:  • Non-contacting – where the sensor is mounted to the vessel and measures the material inside without directly contacting the material  • Contacting – where the sensor is mounted to the vessel and measures the material inside by contacting the material directly • Non-invasive – where the sensor is mounted to the outside of the vessel and measures materials inside without penetrating the vessel or contacting the interior in any way 
But even with these three broad categories, how can operators select the perfect level measurement device for their application? Let’s take a look at  1) Technology  2) Process conditions  3) Maintenance conditions 4) Price.