More than sensors+automation

JUMO NESOS R20 LT – Level Transmitter via Float (408320)


  • Level measurement via floats and reed chain
  • Resolution that is accurate up to 5 m – guarantees precise measurement
  • Transfer via standard signal 4 to 20 mA
  • High protection type up to IP68
  • Level measurement with low filling heights from 0.1 to 4 m
  • No efforts necessary for programming and configuration (Plug and Play)
  • Optional Pt100 or Pt1000 available
  • Approvals for shipbuilding and explosion-protected areas (intrinsically safe and flameproof enclosure)

Customer benefits

  • Proven, maintenance-free measuring principle
  • Customer-specific solutions possible – many materials and forms are available for the float; in-house manufacturing of the float with a high production depth
  • Flexible measurement – level can be determined independently from the container geometry due to the measuring principle
  • Independent from media properties in which foam formation, conductivity (permittivity (ε)), pressure, vacuum, steam, and condensation have an influence
  • Quick error check when servicing
  • High degree of chemical resistance due to availability of different materials
  • Cost-effective installation and mounting
  • Price-performance ratio optimized through the use of standard components and processes


  • Level measurement of liquids in storage tanks and containers
  • Water and wastewater treatment
  • Food and beverages
  • Chemical
  • Petrochemical
  • Gas and oil
  • Mechanical and plant engineering
  • Shipbuilding
  • Energy technology


Level measurement is carried out according to the Archimedes' principle for liquids in a semi continuous manner. The float moves along the guide tube as the level rises or falls. With its magnetic field the magnet in the float actuates the reed chain that is installed in the guide tube. As a result, a resistance value is converted and transmitted into a standard signal 4 to 20 mA. The signal can be evaluated and processed further by downstream electronics. Depending on the variant ordered, various electrical connections, process connections, guide tube lengths, floats, and resolutions are available. With the optional temperature sensor, both the level measurement and the temperature can be acquired via just one measuring point.

The output signal always refers to increasing level.

With the level transmitter, the levels of tanks and containers are transferred with a standard signal.

When connecting to intrinsically safe electrical circuits, the intrinsically safe version of the product [Ex-i] fulfils the requirements for explosion group II of categories 1/2 G and 1/2 D, as well as 2 G and 2 D. It is therefore suitable for use in the potentially explosive area of zone 0, 1, and 2 for gas (G) and zone 21 and 22 for dust (D). Here, a certified, intrinsically safe isolation amplifier in [Ex-ia] must be used.

When connecting to electrical circuits that are not intrinsically safe, the version of the product with flameproof enclosure [Ex-d] fulfils the requirements for explosion group II of category 1/2 G and 2 D. It is therefore suitable for use in the potentially explosive area of zone 0, 1, and 2 for gas (G) and zone 21 and 22 for dust (D).

A separate certificate from TÜV SÜD is available for Pressure Equipment Directive 2014/68/EU.

Approvals are available for applications in shipbuilding.

Further technical information is available in the Documentation category.