SENSOR KAPASITIF SEDERHANA UNTUK MENGUKUR TINGKAT KELEMBABAN GABAH PADI BERBASIS PENGUKURAN DIELEKTRIK

Abstract

We have developed capacitive sensor for measuring the moisture level of rice grain based on dielectric measurement of the electrode. Calibration of the initial moisture level was conducted at BPTP Pekanbaru. Three local rice varieties were tested Anak Daro, Cokan, and Pulut with the grain moisture ranging from 19 % to 32 %. Pulut varieties has maximal output frequency of the LC oscillator at 1.255 MHz with a humidity level of 25.85% while the smallest frequency was obtained from varieties Anak Daro at 1.135 MHz and 29.56% moisture level. The results showed that the moisture level is inversely proportional to the frequency of LC oscillator output. By using the values ​​of the mathematical model equations, the moisture level of grain can be calculated from the value of the frequency with R² values ​​of Anak Daro, Cokan, and Pulut are 0.963, 0.933, and 0.965 respectively.

Keywords: Capacitive sensor, moisture level, dielectric, LC oscillator, rice grain