Study On The Control System On The Flatbed Type Of Counter-Flow Grain Drier

A control system based on microcontroller is developed, according to the characteristics of the 5HPN-3M flatbed type of counter-flow grain dryier, to control the temperature of heated air and the final moisture of grain content.The 5HPN-3M flatbed type of counter-flow grain dryier can fit the condition of china's agricullural production.The temperature of heated air can be adjusted through turning on and off the diesel oil burner, and the final moisture of grain can be controlled through measuring the temprerature of gain near the bottem of flatbed. The control system is composed of AT89C52, a high-powered 8-bit microcontroller, data gathering circuit, real time circuit, data output circuit and system watch circuit. The sensors detect the change of temprerature of air or grain and export analog signal. Then the analog signal is converted to digital signal. The microcontroller compares that with set value, and transferred the control signal to the burner and the unload system..Through the test, the system runs stably and reliably, and the precision.is excellent.