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


  • Level measurement via float and reed chain
  • Resolution that is accurate up to 5.5 mm – guarantees precise measurement
  • Transfer via standard signal 4 to 20 mA
  • Alternatively, a potentiometric output signal is available − among other things − for reduced variants without integrated head transmitter.
  • High protection type up to IP68
  • Reverse voltage protection
  • Error current according to NAMUR NE43
  • Level measurement with low filling heights from 0.1 to 4 m
  • No efforts necessary for programming and configuration (Plug and Play)
  • Optional temperature sensor (Pt100, Pt1000) or temperature switch available
  • Approvals and certificates are available for explosion protection, shipbuilding, railway applications, and the Water Resources Act (WHG) as well as a certification for the Pressure Equipment Directive (PED)

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
  • Unaffected by 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
  • No supply isolator required for versions with explosion protection flameproof enclosure [Ex d]
  • 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 beverage
  • Chemical industry
  • 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. This process converts a resistance value into a standard signal of 4 to 20 mA and transmits it. The signal can be evaluated and processed further by downstreamed electronic components. Depending on the variant ordered, various electrical connections, process connections, guide tube lengths, floats, and resolutions are available. With the optional temperature sensor or temperature switch, the temperature can also be recorded via just one measuring point in addition to the level measurement.

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 [Ex i] of the product fulfills 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 section.


Accessory articles

Article number Product description Price / piece
Ex-i repeater power supply and input isolation amplifier 707530/38 price on request
Line socket 4-pole, M12×1, straight, 2 m price on request
Line socket 4-pole, M12 × 1, angled, 2 m price on request
Mounting element for mounting rail price on request
2-wire level transmitter JUMO NESOS-series price on request
2 Draht Füllst.-Messumf. NESOS-Serie SIL price on request

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