Marmonix MRL-3500 Non-Contact Radar Level Sensor for Liquids

The Marmonix MRL-3500 radar level transmitter is a 26 GHz non-contact sensor for hygienic liquid storage and corrosive containers, with a 20 m measuring range and ±3 mm precision at -40 to 150 ℃. It offers 4–20 mA/HART or RS485/Modbus output, a flange connection, an aluminium IP67 housing and an Exia IIC T6 Ga rating. Browse all Marmonix level transmitters, or compare the MRL-3200 for solids and dust.

Non-contact radar level transmitter MRL-3500

This series of radar level meter Marmonix MRL-3500 adopted 26G high frequency radar sensor, the maximum measurement range can reach up to 70 meters. Antenna is optimized further processing, the new fast microprocessors have higher speed and efficiency can be done signal analysis, the instrumentation can be used for reactor, solid silo and very complex measurement environment.
Radar level transmitter antenna microwave pulse is narrow, the downward transmission antenna. Microwave exposure to the medium surface is reflected back again by the antenna system receives, sends the signal to the electronic circuit automatically converted into level signals (because the microwave propagation speed, electromagnetic wave to reach the target and the reflected back to the receiver this time is almost instantaneous).

Non-contact radar level transmitter MRL-3500 Features

Key features of the MRL-3500 include:

• Small antenna size, easy to install; Non-contact radar, no wear, no pollution.
• Almost no corrosion, bubble effect; almost not affected by water vapor in the atmosphere, the temperature and pressure changes.
• Serious dust environment on the high level meter work has little effect.
• A shorter wavelength, the reflection of solid surface inclination is better.
• Beam angle is small, the energy is concentrated, can enhance the ability of echo and to avoid interference.
• The measuring range is smaller, for a measurement will yield good results.
• High signal-to-noise ratio, the level fluctuation state can obtain better performance.
• High frequency, measurement of solid and low dielectric constant of the best choice.

Non-contact radar level transmitter MRL-3500 Specifications:

Buying guide: Read our level transmitter buyer’s guide.

Questions about the MRL-3500 radar level transmitter

What range does the MRL-3500 measure?

The MRL-3500 specification table and datasheet give a measuring range of 20 m with ±3 mm precision. The overview text mentions up to 70 m for this radar series, so size your tank against the 20 m table value.

Which flanges and antennas fit the MRL-3500?

The MRL-3500 datasheet lists DN80 to DN250 stainless steel 304 flanges (or a custom connection), Φ46, Φ76 or Φ96 mm horn antennas and Viton or Kalrez seals. Electronics are 24 V DC two-wire 4–20 mA (with or without HART), 220 V AC four-wire 4–20 mA or RS485/Modbus.

MRL-3500 or MRL-3200: which should I choose?

Choose the MRL-3500 for hygienic liquid storage or corrosive containers, up to 20 m at ±3 mm and up to 150 ℃, and the MRL-3200 for solids and heavy dust, up to 70 m at ±15 mm and up to 250 ℃. Both use 26 GHz radar, 4–20 mA/HART or RS485/Modbus output, an aluminium IP67 housing and an Exia IIC T6 Ga rating.

Case study: level monitoring in liquid and corrosive storage tanks

In a typical tank farm, storage tanks for clean or corrosive liquids need level measurement that does not touch the product, both for hygiene and to avoid sensor corrosion.

A 26 GHz non-contact radar transmitter mounts on the tank roof and measures the distance to the liquid surface by timing reflected microwave pulses. It is largely unaffected by vapour and temperature changes, and its intrinsically safe rating suits hazardous areas.

Operators connect the 4–20 mA/HART or RS485/Modbus output to the plant control system to track inventory, set high and low alarms, and schedule transfers. Because nothing contacts the liquid, there are no moving parts to clean or replace inside the tank.