Endress+Hauser Micropilot FMR52 Free-Space Radar Level Transmitter

The Endress+Hauser Micropilot FMR52 is a non-contact, free-space radar level transmitter operating in the K-band at approximately 26 GHz. It continuously measures the distance to the product surface and, from the user-entered empty distance, calculates level, volume or mass through a linearization of up to 32 points. Because the microwaves are unaffected by changing media, temperature swings, gas blankets or vapour, the FMR52 delivers a stable measurement where displacer, capacitive or hydrostatic methods struggle.

What distinguishes the FMR52 within the Micropilot family is its completely PTFE-filled, flush-mounted horn antenna in 50 mm (2") or 80 mm (3") size. The wetted parts are limited to PTFE and 316L stainless steel, so the instrument is the natural choice for aggressive liquids — concentrated acids, alkalis, solvents — and for hygiene-sensitive duty in food and life-science plants. The maximum measuring range is 40 m (131 ft) in the standard version and 60 m (197 ft) with the "Advanced dynamics" application package, with a reference measured error of ± 2 mm (0.08 in).

The process side is rated –40 to +200 °C (–40 to 392 °F) and, across the model line, up to 25 bar (363 psi) with the right process connection — but every one of the five units in Barmaan stock is flanged PN 16 and its nameplate reads MWP: 16 bar, so 16 bar is the figure to design around here. The electronics tolerate an ambient range of –40 to +80 °C. All five are 2-wire, loop-powered transmitters with a 4–20 mA HART output (PROFIBUS PA and FOUNDATION Fieldbus versions of the FMR52 exist, but none is in stock); four of the five nameplates read 10.4 to 35 V DC, and the fifth — the intrinsically-safe unit — reads 10.4 to 30 V DC. A tight 10° beam at the 80 mm antenna keeps interference echoes low in cluttered vessels, and up to eight Micropilot transmitters can share one tank thanks to statistically coded pulses.

Hazardous-area approval is the one place these five devices are not alike, so it is stated per device rather than as a property of the page. One unit — the German-built 2020 device with the DN 100 flange — carries ATEX II 1/2 G Ex ia IIC T6–T1 Ga/Gb intrinsic-safety approval on its nameplate (PTB 12 ATEX 2018 X, XA00677F-D). The other four were built in Suzhou in 2023 and 2024 and their nameplates show CE, an FCC ID and the IP rating with no Ex marking; this listing makes no Ex claim for them. All five plates read IP68/IP66 (NEMA 6P/4X). The FMR5x line is developed to IEC 61508 for use up to SIL 2, or SIL 3 in homogeneous/heterogeneous redundancy, independently assessed by TÜV Rheinland — a property of the model line, and none of these five plates carries a SIL marking of its own.

Five units are physically in Barmaan's warehouse, and each was photographed on its own — nameplate and flange stamp included — before this page was written. They divide into three process connections: two on DN 50 PN 16, two on DN 80 PN 16 and one on DN 100 PN 16, all EN 1092-1 type 05 B1 in 1.4404/316L. Each unit's card states the size stamped into its own flange, its factory order code (FMR52-4VL3/0, FMR52-4UW0/0 or FMR52-LEH6/0) and the build year printed on its plate — 2020, 2023 and 2024. The three units still carrying their E+H Suzhou range tag are configured for L = 0 … 40 000 mm.