Endress+Hauser Micropilot M FMR245 Radar Level Transmitter

The Endress+Hauser Micropilot M FMR245 is a two-wire, loop-powered free-space radar level transmitter for the continuous, non-contact measurement of liquids, pastes and slurries. It operates in the K-band (approx. 26 GHz) using the time-of-flight principle: short radar pulses are emitted by the antenna, reflected off the product surface and received again, and the microprocessor derives the level from the travel time. Because the measurement is contactless it is unaffected by density, dielectric constant, temperature, pressure or vapours to a large degree, which makes it a robust replacement for float, capacitance and differential-pressure systems.

The distinguishing feature of the FMR245 is its fully PTFE-clad, encapsulated antenna, offered as 50 mm (2") or 80 mm (3"). The PTFE cladding conforms to FDA 21 CFR 177.1550 and USP Class VI. The model line's 3-A and EHEDG hygienic approvals are granted only to the Tri-Clamp process connections (TDK / TFK / THK in the ordering table); the four units offered on this page are all flanged builds, so none of them carries a hygienic approval. The PTFE construction is what lets the current antenna options reach +200 °C at up to 16 bar, which is why the FMR245 is known as the high-temperature, chemically resistant member of the Micropilot M family.

In its basic version the FMR245 measures up to 40 m (131 ft); the advanced-dynamics option F or G extends the range to 70 m (230 ft). All four units on this page are basic-version builds, so each of them is a 40 m instrument. Under reference conditions the reference accuracy is ±3 mm and the resolution is 1 mm. The output is 4-20 mA with HART protocol on a standard two-wire loop (PROFIBUS PA and FOUNDATION Fieldbus variants exist in the model line), rated up to SIL 2 for overfill and level monitoring. The model line is certified under several hazardous-area schemes — ATEX Ex ia and Ex d [ia], IECEx, NEPSI and FM/CSA — and each of these are different certificates, not grades of one: the units below are labelled with the scheme printed on their own nameplate. The dual-compartment aluminium (F12 / T12) or 316L (F23) housing is rated IP65 / NEMA 4X while the antenna itself is IP68.

Four second-hand units are held in Barmaan's warehouse and they are not interchangeable. Two of them (built 03/2012 in Suzhou, order code FMR245-5CCMKAC2A) carry an 80 mm (3") antenna rated to 200 °C on a DN80 PN10/16 PTFE-lined flange to EN 1092-1, with ATEX Ex d [ia] IIC T6 flameproof protection. One (built 11/2007 in Maulburg, order code FMR245-24APKAA4A) sits on a 4" 150 lb ASME B16.5 PTFE-lined flange with ATEX Ex ia IIC T6 intrinsic safety, and its nameplate rates its antenna at 150 °C rather than 200 °C — it is an earlier build whose antenna option predates the current ordering table. One (built 04/2011, order code FMR245-TCALKAC4A) has an 80 mm antenna rated to 200 °C on a 3" 150 lb ASME flange and is certified to FM XP Class I Division 1 Groups A-D with a NEMA 4X enclosure, carrying no ATEX marking at all. Each unit is listed below with its own order code, approval and process connection, read from its own nameplate.