Rosemount 5400 Two-Wire Non-Contacting Radar Level Transmitter

Overview

The Rosemount 5400 is Emerson’s two-wire non-contacting radar level transmitter, which the product data sheet describes as easy to install and virtually unaffected by process conditions. It is offered in two frequency versions: the Rosemount 5402, a high-frequency radar at about 26 GHz that is the preferred choice for most liquid and many solids applications, and the Rosemount 5401, a low-frequency radar at about 6 GHz designed for tough conditions with turbulence, foam, condensation and deposits. The Rosemount 5400 has a large installed base on storage tanks, reactors and silos, and is supported with HART, FOUNDATION Fieldbus and Modbus electronics.

Seven Star LLC supplies the Rosemount 5400 to refineries, petrochemical plants, utilities, mining and cement operations, and EPC contractors in Oman and the GCC, from our office in Muscat. Many plants in the region standardised on this transmitter in earlier project phases, so like-for-like supply helps maintenance teams keep spare parts, configuration files and training consistent.

Measurement Principle

According to Emerson, the Rosemount 5400 measures the distance to the surface with short radar pulses. When a pulse reaches the medium, part of the energy is reflected back to the transmitter, and level, volume and level rate are calculated from the time difference between the transmitted and the reflected pulse. Turbulence, foam and long measuring ranges can reduce the reflected energy, so Emerson uses a dual port technology that helps detect the surface in challenging applications.

The data sheet lists the benefits of the non-contacting method: no compensation is needed for changing process conditions, there are no moving parts and no recalibration is required, and the technology is ideal for dirty, coating and corrosive applications. As general engineering context, the choice between the two versions is mainly about beam width and robustness: the 26 GHz Rosemount 5402 produces a narrow beam that fits valves, taller nozzles and smaller openings, while the 6 GHz Rosemount 5401 uses a wider beam that is more tolerant of condensation, vapour, dust and build-up on the antenna.

Engineering Design of the Rosemount 5400

The Rosemount 5400 has a robust, shock-resistant and vibration-proof design with a detachable head that allows the tank to remain sealed during maintenance. Circular polarisation minimises installation constraints. Antenna options include stainless steel cone antennas from 2 inch to 8 inch, a condensation-resistant process seal antenna and, for the Rosemount 5402, a parabolic antenna with a 4.5° beam for long-range and solids duties. The data sheet gives beam angles such as 19° for the 2 inch cone and 9° for the 4 inch cone on the 5402, compared with 37° for the 4 inch cone on the 5401.

The 4–20 mA HART version is loop powered from 16 to 42.4 Vdc (16 to 30 Vdc in intrinsically safe applications), and the HART signal can feed a Rosemount 333 HART Tri-Loop for up to three additional analogue outputs or a Wireless THUM Adapter for WirelessHART access to diagnostics. FOUNDATION Fieldbus and Modbus versions are also offered. Process temperature and pressure depend on the antenna and seal; the cone antenna is rated up to 16 bar and 150 °C at the flange, and the parabolic antenna is rated for -0.5 to 0.5 bar up to 200 °C.

Key Features

The Rosemount 5400 data sheet highlights the following features.

• Dual port technology improves reliability with disturbing factors and longer measuring ranges.
• Two frequency versions, 26 GHz (5402) and 6 GHz (5401), match narrow-beam or rugged duty requirements.
• Instrument accuracy is 3 mm for the 5402 and 10 mm for the 5401 at reference conditions.
• A maximum measuring range of 35 m from the flange covers tall storage tanks and silos.
• Condensation- and dirt-resistant antennas maximise uptime in difficult vapour spaces.
• A detachable head allows electronics service while the tank remains sealed.
• HART, FOUNDATION Fieldbus and Modbus outputs ease plant integration, with Tri-Loop and THUM options.
• A diagnostics suite with Signal Quality Metrics helps detect antenna contamination or loss of signal strength.

Industrial Applications

Emerson lists storage and buffer tanks, reactor and mixing tanks and solids measurement as core applications for the Rosemount 5400, noting that the 5402 with a 4 inch cone or parabolic antenna suits silos with rapid level changes because the narrow beam avoids internal obstructions. In Oman this matches crude and product tanks at refineries, sour water and amine tanks at gas plants, chemical reactors and blend tanks in Sohar, cement and clinker silos, and storage at desalination and power plants. The low-frequency Rosemount 5401 is a common choice where heavy condensation or foam is expected. Because both versions share the same housing concept, electronics options and configuration tools, a site can keep one family of radar transmitters across clean storage, dirty process and bulk solids duties, which simplifies spare parts, training and documentation for the maintenance team.

Seven Star LLC supplies the Rosemount 5400 throughout the Sultanate of Oman and the GCC, and can help customers decide between it and newer Rosemount radar designs. Related instruments include the Rosemount 5408 non-contacting radar level transmitter, the Rosemount 5300 guided wave radar level transmitter for interface and low-dielectric duties, and the Rosemount 2140 vibrating fork level detector for independent point level alarms.

Technical Specifications

The following Rosemount 5400 data is taken from Emerson product data sheet 00813-0100-4026.

How to Order

To order the Rosemount 5400, send Seven Star LLC an RFQ with the product, tank height, nozzle size, pressure and temperature, required output and certification, or the full model code of an existing unit for like-for-like replacement. The Emerson product data sheet can be downloaded from this page. Seven Star LLC supplies Rosemount radar transmitters from Muscat across Oman and the GCC, with sourcing and model selection support.