The Endress+Hauser Levelflex FMP51 is a guided wave radar transmitter designed for continuous level and interface measurement in liquids, pastes and slurries. It is the standard sensor for demanding process applications where temperature, pressure, foam, moving surfaces or vessel internals can challenge conventional level technologies.

How Guided Wave Radar Works

High-frequency microwave pulses travel along a rod, rope or coaxial probe. When the pulses reach the product surface, part of the energy is reflected to the transmitter. The measured travel time is converted into an accurate level value. Because the signal is guided along the probe, measurement is not affected by changing media properties, gas blankets, vapors or temperature changes.

Built for Demanding Applications

The FMP51 can be evaluated for chemical storage, oil and gas processes, power generation, water treatment and other industrial vessels. Its guided signal supports stable measurement when the liquid surface is moving, foam is present or multiple tank baffles create potential interference.

• High-temperature and high-pressure vessels

• Storage and buffer tanks with vapors or gas blankets

• Liquid interface applications

• Agitated vessels with moving surfaces

• Applications requiring explosion protection, SIL, overfill prevention or marine approvals

Rod, Rope or Coaxial Probe?

Rod probes suit shorter ranges and many general process vessels. Rope probes provide long measurement distances for tall tanks. Coaxial probes offer a defined signal path and can be useful where surrounding vessel geometry is especially difficult. Final selection should consider dielectric constant, tank height, nozzle geometry, agitation, internals and available mounting clearance.

Commissioning and Diagnostics

HistoROM data management helps simplify commissioning, maintenance and device replacement. Multi-Echo Tracking supports dependable echo evaluation, while Heartbeat Technology provides diagnostic and verification functions. During commissioning, confirm probe length, empty and full calibration, blocking distance, product properties and the actual process conditions.

Why the Complete Order Code Matters

“FMP51” identifies the product family, but the complete order code defines the probe, process connection, wetted materials, electronics, approvals and options. For accurate quotation or replacement, please provide the full nameplate code, for example:

FMP51-BAACCABCB3ARJ+AA, 7000 mm

For a new application, also provide the medium, vessel height, temperature, pressure, process connection, interface requirement, output signal and required approvals.

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