The Endress+Hauser Levelflex FMP55 uses original Sensor Fusion technology (Guided Wave Radar + Capacitance) to continuously measure oil/water and emulsion layer interfaces (-40 to +200°C, vacuum to 40 bar).
We provide factory-direct quotes, NACE MR0175/MR0103 compliance docs, and custom sizing support for separator vessels within 24 hours.
In crude oil separators, desalters, and chemical extraction columns, traditional displacer gauges or single-frequency radar transmitters fail when an emulsion or "rag layer" builds up. A standard radar signal gets absorbed or scattered in the emulsion zone, leading to false high-water trips, pump cavitation, or undetected water carryover into downstream distillation columns. Levelflex FMP55 solves these exact site headaches:
The spec table below outlines the mechanical, thermal, and electrical limits required by instrument engineers when sizing Levelflex FMP55 for oilfield separators, chemical tanks, and marine vessels.
| Technical Parameter | Specification Value | Engineering Selection Note |
|---|---|---|
| Measurement Principle | Guided Wave Radar + Capacitance (Sensor Fusion) | Dual evaluation on a single fully insulated probe |
| Measurement Accuracy | ±2 mm (±0.08 in) | High accuracy for both level and interface outputs |
| Process Temperature | -40 to +200 °C (-40 to +392 °F) | Ideal for heated crude desalters and hot solvent tanks |
| Process Pressure Rating | Vacuum to 40 bar (580 psi) | Handles high-pressure production separators |
| Probe Configurations | Rod (up to 4m), Cable (up to 10m), Coaxial (up to 6m) | Insulated PTFE/PFA prevents electrical shorting in water |
| Min. Dielectric Constant (DK) | DK > 1.4 (Upper non-conductive medium) | Requires DK difference ΔDK ≥ 10 between upper & lower liquid |
| Wetted Materials | 316L, PTFE, PFA | Conforms to NACE MR0175 / MR0103 sour gas standards |
| Process Connections | Flanges: ASME 1 1/2"...6", DN50...DN150, JIS 10K | Threaded 1½" options available on specific configurations |
| Communication Protocols | 4–20 mA HART, PROFIBUS PA, FOUNDATION Fieldbus | 2-wire or 4-wire HART options available |
| Safety & Marine Approvals | SIL3 (IEC 61508), WHG, GL, ABS, LR, BV, DNV | ATEX, IECEx, FM, CSA, NEPSI explosion-proof certified |
Instrument engineers often ask whether standard guided wave radar (FMP51) can handle interface jobs. In clean, sharp oil-water separations, FMP51 works well; but when emulsion or rag layers exist, FMP55 is the necessary upgrade to prevent signal loss.
| Selection Parameter | Levelflex FMP55 (Radar + Capacitance) | Levelflex FMP51 (Standard Guided Radar) |
|---|---|---|
| Emulsion / Rag Layer Performance | Continuous & Stable (Sensor Fusion) | Signal echo lost or misread in thick emulsion |
| Measurement Technology | Dual Tech: Guided Radar + Capacitance | Single Tech: Guided Wave Radar |
| Interface Signal Calculation | Capacitance measures dielectric profile directly | Relies purely on microwave reflection at sharp boundary |
| Max Process Temperature | +200 °C | +450 °C (High-temperature option available) |
| Max Process Pressure | 40 bar (580 psi) | 400 bar (5,800 psi) |
| Primary Application | Oil/water separators, desalters, rag layer tanks | Clean liquid storage, bypass chambers, high-temp oil |
A: Standard radar pulses scatter when encountering a gradual dielectric shift inside emulsion zones. Levelflex FMP55 uses radar to measure top level and simultaneously uses its insulated probe to calculate continuous electrical capacitance changes. Because capacitance directly responds to the ratio of water vs. oil around the probe, it pinpoint-tracks the exact water interface regardless of emulsion thickness.
A: Yes. FMP55 holds major international marine approvals (GL, ABS, LR, BV, DNV) and wetted metal components strictly conform to NACE MR0175 and MR0103 standards, preventing sulfide stress cracking in hostile sour crude applications.
A: For turbulent tanks with strong lateral fluid forces, rigid rod probes (up to 4m) or coaxial probes (up to 6m) are recommended. If specifying a long cable probe (up to 10m) in high-flow separators, the cable end must be anchored using a bottom weight or mounting bracket to prevent the insulated probe from touching the vessel wall.
Need immediate pricing for Endress+Hauser Levelflex FMP55, custom probe length calculations, or NACE certification? Contact our application engineers today for official datasheets, delivery lead times, and factory-direct quotes.
