Rancang Bangun Sistem Pengendalian Suhu dan Kelembaban Berbasis PID Pada Pengering Tipe Rotari Kabinet Untuk Pengeringan Cabai Merah

Abstract

Cabai merah (Capsicum annuum L.) merupakan komoditas hortikultura strategis yang memerlukan pengeringan terkontrol untuk mempertahankan mutu dan memperpanjang umur simpan. Penelitian ini bertujuan merancang sistem pengendalian suhu dan kelembaban berbasis PID pada pengering tipe rotari kabinet, menganalisis efektivitas pengendalian, mengevaluasi kinerja respons sistem, serta menganalisis kinerja pengeringan cabai merah pada lima kombinasi perlakuan setpoin suhu, kelembaban relatif, dan nilai minimum kipas. Sistem dibangun menggunakan mikrokontroler ESP32 dengan dua loop kontrol independen. Loop suhu mengendalikan elemen pemanas melalui SSR dan loop kelembaban mengendalikan kipas DC. Parameter PID suhu diperoleh melalui metode ZieglerNichols dan fine-tuning. Sistem berhasil mempertahankan suhu dengan steady-state error 0,05-0,29°C, sedangkan pengendalian kelembaban efektif pada setpoin rendah namun mengalami keterbatasan pada setpoin tinggi akibat penurunan laju penguapan air bahan pada fase falling rate. Seluruh perlakuan berhasil mencapai kadar air akhir sesuai SNI 3389:2023 dengan durasi 12-21 jam. Perlakuan P1 menghasilkan laju pengeringan tertinggi sebesar 59,18%bk/jam, mekanisme rotasi bahan menghasilkan keseragaman kadar air akhir antar rak dengan selisih 0,01- 0,04%bk. Total konsumsi energi listrik seluruh perlakuan berada dalam rentang yang sempit, yaitu 3,037-3,123 kWh meskipun durasi pengeringan berbeda sangat jauh.

Red chili (Capsicum annuum L.) is a strategic horticultural commodity that requires controlled drying to maintain quality and extend shelf life. This study aimed to design and build a PID-based temperature and humidity control system for a rotary cabinet dryer, analyze control effectiveness, evaluate system response performance, and analyze red chili drying performance under five treatment combinations of temperature setpoint, relative humidity setpoint, and minimum fan speed. The system was built using an ESP32 microcontroller with two independent control loops i.e. temperature and humidity. The heating element via SSR was controlled by temperature loop while DC exhaust fan was controlled by humidity loop. PID temperature parameters were obtained through Ziegler-Nichols tuning and fine-tuning. The system successfully maintained temperature with a steadystate error of 0.05-0.29°C, while humidity control was effective at low setpoints but limited at high setpoints due to reduced moisture evaporation rate during the falling rate period. All treatments achieved final moisture content below 11% wet basis in accordance with SNI 3389:2023 within 12-21 hours. P1treatment produced the highest drying rate of 59,18%db/hour, the tray rotation mechanism achieved excellent drying uniformity with inter-tray moisture content difference of only 0.01- 0.04%db, and total energy consumption across all treatments remained within a narrow range of 3.037-3.123 kWh despite significantly different drying durations.