On-line resistance-type grain moisture tester and control method thereof

The invention discloses an on-line resistance-type grain moisture tester and a control method thereof. The tester comprises a transporter and a detection control device, wherein the detection control device comprises two grinding wheels on the rear end of the transporter, an operational amplifier the reverse input end and the syntropy input end of which are respectively connected with the two grinding wheels, an A/D (analog-digital) converter the input end of which is connected with the output end of the operational amplifier, and a control end connected with the output end of the A/D converter, wherein one grinding wheel connected with the reverse input end of the operational amplifier is connected in series with a fixed value resistor, and the control end is connected with a dryer controller. The on-line resistance-type grain moisture tester provided by the invention adopts intelligent automation operation; and when a grain drying machine operates, the tester can automatically carry out periodic detection on grain moisture and the inner temperature of the dryer according to parameters set by users and compare the detected result with the preset parameters, and other related operations are also automatically executed.