Radar Level Measurement

Radar Level Measurement

Radar level measurement (free space) provides continuous level measurement in liquids and solids using non-contact radar sensors. The device transmits electromagnetic energy toward the product surface and measures the return signal to determine distance, converting that distance into level based on installation geometry. Because the measurement is non-contact, it avoids wetted components and is frequently chosen for corrosive, hot, or hygienically sensitive services where probe contact is undesirable.

Key benefits include low maintenance and strong performance across wide pressure and temperature ranges, since the electromagnetic path does not depend on the speed of sound or liquid conductivity. Modern radar techniques can deliver high accuracy and stable readings even with vapor space effects that complicate ultrasonic methods. In solids, radar can be effective in dusty silos when the installation is designed to manage echo clutter and signal attenuation.

Application success depends on achieving a clean measurement path. Internal structures (ladders, coils, agitators, braces) can create false echoes, so nozzle placement, aiming, and echo mapping are important. Certain products - especially those with very low reflectivity, heavy foam, or severe condensation - may require antenna selection changes, higher frequency instruments, or mechanical aids such as stilling wells or waveguides to stabilize the surface and reduce spurious reflections.

Typical applications span tank farms and terminals, chemical and petrochemical storage, pressurized vessels, and water/wastewater reservoirs. In bulk solids, radar is used for inventory measurement in silos storing powders, granulates, and pellets, and for level control in hoppers where contact methods are impractical due to abrasion, contamination risk, or mechanical constraints.

Selection typically addresses frequency band and antenna style, process connection and nozzle geometry, and the vessel’s internal “echo environment.” Integration work often includes defining blocking distances near the antenna, configuring damping for fill/empty dynamics, and aligning diagnostic/alarm behavior with operational response. When used for overfill prevention, installation quality and proof-test strategy are central to achieving dependable protection layers.

George E. Booth Co., an exclusive authorized representative of sales and service for Endress+Hauser.