DEVELOPMENT OF AUTOMATIC CONTROL SYSTEM FOR SOLAR DRYING CABINET
Keywords:
Solar dryer, Automatic control system, Drying cabinet, Temperature controlAbstract
This paper presents the design of thin layer direct mode solar drying cabinet with moisture and temperature automatic control system. Two motors with ArduinoTM microcontroller were used to control the air inlet and outlet of solar drying cabinet. The speed of two fans was controlled by thermometer and relative humidity sensors. The electric power of motors and controller were supplied by PV-cell with battery for low light and night time drying. The temperature from inlet reached around 36.1oC to 46.6oC, the relative humidity reduced from 55%RH to 21%RH in the cabinet. The Chinda Chili was used as a demonstration drying product to compare automatic solar drying cabinet with normal sun drying. Automatic solar drying cabinet could reach the moisture ratio to 0.3 in 7 hours which showed 2 times of Moisture ratio compared with normal sun dryer.
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