Mobrey MLT100 SMART HART Displacer Level Transmitter

Displacer level transmitter with HART output for vessels and chambers

The Mobrey MLT100 is a two-wire, loop-powered displacer level transmitter that couples the buoyancy principle with LVDT electronics. A displacer made to length for each order hangs from the head on a spring arrangement designed to reduce friction. As the liquid level rises or falls the displacer moves a core inside the stainless steel pressure tube, and a linear variable differential transformer around the tube produces a signal proportional to the core position. The transmitter outputs 4-20 mA with HART superimposed and can measure level, content or interface.

The datasheet describes a small mounting envelope, a choice of direct vessel mounting or external mounting in a chamber, integral or remote electronics, and wetted parts in a wide range of materials. Flameproof construction is available for Zone 1 areas.

Technical specifications

Model code and construction options

The model code is built from eleven tables. The base model is LT. Flange material is carbon steel (C), stainless steel (S) or no flange with a 1-inch NPT connection (N). Flange sizes cover 3 and 4 inch ASME B16.5 Class 150, 300 and 600 raised face, and DN80 and DN100 in PN16, PN25 and PN40, with a further list of 1 to 2 inch flanges for chamber connections. The enclosure is selected from ZF (IP66 safe area, cast iron), TF (Ex d flameproof cast iron), TR (Ex d with remote electronics in an IP66 aluminium enclosure for the non-hazardous area) and TG (Ex d, AISI 316 stainless steel).

A display option adds a two-line LCD in a cast aluminium Ex d enclosure. The spring and displacer codes are assigned by Delta Mobrey from the process conditions, and chamber style codes cover side-bottom and side-side arrangements with vent and drain options. A typical model number printed in the datasheet is LT C 61 TS A D * * B 11 00.

Calibration, materials and application notes

Local adjustment of the 4 mA and 20 mA points and damping can be made with the Mobrey Magnetic Scroller and the Caliplug, which also carries a heartbeat LED that flashes every 3 seconds. Remote ranging uses a HART Field Communicator. Pressure-retaining parts are hydrostatically tested to at least 1.5 times working pressure, welding is qualified to ASME IX, BS EN 287 and EN ISO 15614-1, and NDT such as radiography and dye penetrant is available when specified at order. The datasheet lists process plants, water treatment, power plants and oil, gas and petrochemical service as typical uses.

Documents and quotation

Before ordering, confirm the vessel connection, flange rating, fluid density and interface density, displacer length, process temperature and pressure, enclosure and hazardous-area requirement. The displacer and spring are unique to each instrument, so they must be specified from process data.

The manufacturer document is attached to this page and listed below. Seven Star LLC is an independent supplier in Muscat and can quote against the model code, quantity and delivery location. Browse more instruments in Level Instrumentation, or see the Mobrey brand page.