Early recognition of fluctuations

The MicroPolar system provides real-time, continuous measurement of moisture or dry matter content in a wide range of products. The measurement is performed directly on the main stream. This microwave measurement is nonintrusive; no sensor comes into contact with the product to be measured, which reduces maintenance. The measurement is not influenced by the colour, viscosity or inhomogeneity of the product. Moreover, the measurement is carried out on the entire product. The MicroPolar system is easy to install. The processing unit has a large display and a user-friendly interface. Calibration can also be performed on site.


  • Measure moisture content of a representative section across the measurement path
  • Nonintrusive measurement
  • Highly representative due to transmission principle
  • Easy to install on existing pipelines, vessels, and conveyors
  • Smooth handling and operation
  • Robust system design


Customer benefits

  • Measures moisture across a representative product path
  • Energy reduction in drying processes
  • Increased yield through reduced amount of rejects
  • Free of wear and maintenance
  • Online process control for real-time process information



Measuring principle and function

The installation possibilities are manifold, common installation situations are e.g. on pipes, belt conveyor, shafts / chutes. Possible applications are on all types of cereals, grains and powder products including maize, semolina and couscous, as well as soya, rice, coffee, starch, nuts, rice, etc.

The microwaves pass through the product to be measured, causing the free water molecules, which have excellent dielectric properties, to rotate. This rotation causes a slowing down (phase shift) and a decrease in amplitude (attenuation) of the microwaves, resulting in a very accurate measurement of the water content. Thanks to the multi-frequency technique used by Berthold, measurements are highly reliable and stable and are not affected by reflectance or resonance. The integrated reference signal ensures excellent compensation for the influence of environmental parameters. As the device generates very low power microwaves (in the range of 0.1 mW), the measured product is not subject to any temperature increase or change. The radio licenses of the system have been approved by FCC, IC and ETSI.


Moisture measurement on cereal, grains & powders Application brochure

English | PDF | 612.3 KB

LB 571 Microwave resonator Product brochure

English | PDF | 508.8 KB

Medición de humedad en cereales, granos y polvos Folleto de aplicación

Español | PDF | 611.1 KB