Humidity is one of the most important characteristics and indicators of grain quality. It is determined at the time of acceptance of grain for storage, because this indicator depends not only on the percentage of nutrients in the grain, but the allowable period of storage. Excess moisture can trigger excessive growth of microorganisms, mites, insects, to cause fermentation, swelling, and other physiological and physico-chemical processes. Wet grain can not be stored, so it is subjected to further drying. Processing of wet grain is also difficult.