RANCANG BANGUN SISTEM KONTROL KADAR AIR GABAH PADA ALAT PENGERING GABAH BERBASIS MIKROKONTROLER ATMEGA 8 DESIGN OF PADDY MOISTURE CONTENT CONTROL SYSTEM ON THE PADDY DRYER MACHINE BASED ON ATMEGA 8 MICROCONTROLER

Abstract

Abstrak

Penelitian ini bertujuan untuk merancang sistem kontrol kadar air gabah pada alat pengering gabah dengan set point 14%, untuk mengetahui cara kerja sistem kontrol kadar air gabah dan untuk menganalisis pemodelan difusi massa air pada model gabah silinder. Sistem kontrol kadar air gabah menggunakan mikrokontroler ATMega 8 yang keluarannya mempengaruhi kondisi kerja saklar transistor sehingga memicu relay untuk menyalakan atau mematikan pemanas. Input dan output setiap blok sistem didefinisikan sehingga diperoleh diagram blok keseluruhan sistem. Pemodelan difusi massa air model gabah silinder dianalisis menggunakan persamaan moisture ratio dalam sistem koordinat silinder. Hasil penelitian menunjukkan bahwa sistem kontrol kadar air gabah bekerja dengan baik sesuai set point yang diinginkan. Saat kadar air gabah di atas 14%, pemanas menyala dan saat kadar air gabah kurang dari atau sama dengan 14% pemanas mati. Pola distribusi moisture ratio pada gabah mengalami penurunan disertai fluktuasi dari pusat koordinat. Semakin bertambahnya waktu, fluktuasi makin berkurang dan membentuk pola steady-state.

Kata kunci: sistem kontrol, kadar air, gabah, difusi massa air.

Abstract

This research aimed to design a paddy moisture content control system on the paddy dryer machine with a set point of 14%, to determine the working principle of the paddy moisture content control system, and to analyze modeling the mass of water diffusion on paddy cylindrical model. Paddy moisture content control system was designed by using an ATMega 8 microcontroller that the output could affect the working conditions of transistor that triggered the relay to turn on or turn off the heater. Then, each input and output of each block in the system was defined to obtain the block diagram of the whole system that described the working principle of the system. Modeling the mass of water diffusion on paddy cylinrical model was analyzed by using equation of mass diffusion on cylindrical coordinate system. The results showed that paddy moisture content control system can work well according to set point. If the paddy moisture content was above 14%, the heater will turn on and if the paddy moisture content was less than equal to 14%, the heater will turn off. The moisture ratio decreased from the center position coordinate with fluctuation. If time increases, the fluctuation diminished and formed a pattern of steady-state.

Keywords: control system, moisture content, paddy, the mass of water diffusion