Rancang Bangun Sistem Pengujian pada Penentuan Massa dan Tekanan Tabung Gas LPG menggunakan LoadCell Hx711 dan Sensor Tekanan

Abstract

The 3-kg Liquefied Petroleum Gas (LPG) cylinder is a widely used household energy source in Indonesia and is classified as a Prepackaged Commodity (BDKT), which mandates strict quantity verification under legal metrology regulations. Discrepancies between the actual content and the declared weight on the cylinder may lead to consumer losses and legal violations. This study aims to design and implement a microcontroller-based testing system for accurately measuring both the mass and internal pressure of 3-kg LPG cylinders. The system employs a Load Cell HX711 and a pressure sensor integrated with an ESP32 microcontroller. Sensor outputs are calibrated and converted into physical units, with real-time measurements displayed on an LCD screen. System evaluation was conducted through testing multiple LPG cylinder samples with varying content levels. The results demonstrate that the system achieves high accuracy, with an average mass deviation of 0.46% and a pressure deviation of 0.37% compared to standard measuring instruments. These findings confirm the system’s reliability and suitability for practical field verification of LPG cylinder contents. The proposed system offers a cost-effective and efficient solution for supporting regulatory inspections, detecting fraudulent practices, and enhancing consumer protection through precise quantity assurance.