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JUMO MAERA S28 - Level Probe (404392)


  • Measuring ranges: 0 to 250 mbar – 0 to 10 bar
    (0 to 2.50 mWS – 0 to 100 mWS)
  • Medium temperature 0 to 50 °C
  • Piezoresistive silicon sensor
  • Excellent long-term stability
  • High overload resistance
  • Integrated overvoltage protection
  • Indirect cable break monitoring
  • Sturdy level probe for indoor or outdoor installation
  • Optionally available with integrated temperature sensor Pt100

Customer benefits

  • Process reliability
    The output signal has a minimum current of 4 mA allowing the electrical circuit to be indirectly monitored for cable/wire breakage with ease. The integrated overvoltage protection prevents the effects of lightning that could lead to destruction of the level probe, thereby offering maximum process reliability. Its core is a piezoresistive measuring cell that is safe and reliable due to its high overload resistance and longevity. 

  • Versatile
    A broad spectrum of measuring ranges and electrical outputs as well as a large number of process connections guarantee variant diversity that can be specifically adapted to any application. Simultaneous measurement of level and temperature may be accomplished with a Pt100 temperature sensor. Costs can be reduced to a minimum with an easier installation and startup.


Level and level measurement for

  • Water and sewage water management
  • Well and surface water

Product comparison level probes


Level probes are used for hydrostatic filling level measurement in tanks or to determine levels (e.g. in open waters).

The level probe can measure filling heights from 0 to 2.5 m – 0 to 100 mWS (water column). Thanks to its sturdy structure and the used materials the device can be mounted indoors or outdoors. If mounted outdoors, the probe comes with integrated overvoltage protection to protect the level probe in the event that lightning strikes the body of water.

When determining the filling height one must consider that every liquid has its own temperature-dependent density. This means that the density value of a liquid having a temperature of 5 °C is different to that of a liquid having a temperature of 30 °C. This data is listed in tables. To be able to simultaneously record the temperature changes of the liquid during measurement, an optional version with integrated Pt100 temperature probe is available.

Further interesting information can be found in the brochure "Level Probes - Hydrostatic Level and Filling Level Measurement".

Further technical information is available in the Download area.


Accessory articles

Article number Product description Price / piece
Terminal box with pressure compensation price on request

(in stock)

Cable holder price on request

(in stock)

Sealing screw price on request
Pressure equalization filter for cable price on request

(in stock)