Microwave moisture sensing system in drying process for green teaproduction

摘要

A microwave moisture meter used in a drying process for green teaproduction is described. It can measure the leaves of green teacontaining the moisture of 40 to 100 percent in dry basis. It is atransmission type of 9.4 GHz waves. To eliminate the variation in thelayer thickness the sample weight is controlled. The moisture content isobtained from the ratio of the microwave attenuation to the weight ofthe leaves. Averaging the data with a computer the moisture content weremeasured in the error of 3% of moisture values. It is better than theerror of the conventional measurement by the feeling of a skilledworkman's fingers actually used in factories