Radar Level Transmitter

Non-contact radar has become the default level technology for tanks. The transmitter emits a microwave signal from an antenna at the top of the vessel; the signal reflects off the product surface and the transmitter measures the time of flight. Nothing is in contact with the product, so the reading is independent of density, temperature, pressure, foam to a degree, and coating, and there is nothing to wear or corrode.

Transmitters measure up to 60 m at process conditions to 100 bar and 482 °C. Antennas are horn, rod or lens types in 316 stainless steel, PTFE, Hastelloy or Monel, chosen for the medium and the nozzle, and a purge connection keeps the antenna clean in dusty or condensing service. Mounting is top-mounted on a flange, threaded connection or still pipe.

Outputs are 4–20 mA HART or FOUNDATION Fieldbus. Smart diagnostics monitor echo quality and signal strength, and built-in verification and proof-test routines let the transmitter be checked without emptying the tank or climbing it, which matters for overfill prevention systems.

Applications are liquid and solids level in storage and buffer tanks, reactors, mixers and silos across oil and gas, petrochemical, chemical, power, water and general process industries. For narrow vessels, very low dielectric liquids, interface measurement or heavy vapour, the guided wave radar is the better choice.