There are a number of technologies that have been used for the moisture measurement including:
Of the technologies available, near infra red and microwave transmission techniques have probably been the most widely adopted.
This is because the limitations of the other technologies preclude their use in a number of applications. Of these two technologies, the microwave transmission technique has significantly fewer limitations compared to NIR:
The moisture content of the material is determined by measuring the transmission of a microwave beam through the process material. This beam is emitted from a transmitter located in the lower arm of the Measurement C-Bracket located under the conveyor belt. The transmitted microwave signal is detected by the receiver located in the upper arm of the Measurement C-Bracket. The effect on the microwave signal by the material it passes through is recorded and used in the determination of the moisture content.