What are the common methods of level measurement?

Common level measurement methods include: Direct methods - sight glasses, float-based (magnetic level indicators), displacer transmitters; Pressure-based - differential pressure (for open and closed tanks), bubbler systems; Electronic methods - ultrasonic, radar (guided wave and non-contact), capacitance, and conductivity probes. Selection depends on process conditions, accuracy requirements, tank type, and medium properties (liquid, solid, foam presence).