ESP32 and MIT App Inventor-Based VRLA Battery Telemetry Monitoring System for Preventive Maintenance
Manual monitoring of Valve Regulated Lead Acid (VRLA) batteries in industrial electrical systems is considered inefficient and risks delayed fault detection. This study aims to design an Internet of Things (IoT)-based telemetry monitoring system to automate the process. The system comprises a PZEM-016 sensor for reading battery voltage, an ESP32 microcontroller as the data processor, Firebase as the cloud database, and an Android application built with MIT App Inventor as the user interface. Voltage data is sent in real-time from the sensor to the ESP32 via Modbus RTU communication through an RS485 to TTL converter, then forwarded to Firebase via Wi-Fi, and finally displayed on the application. Test results show a sensor reading accuracy of 99.60% with an average error of only 0.40%. The system successfully transformed the monitoring method from a manual inspection taking approximately 10 minutes per unit to real-time automatic monitoring. Therefore, the designed system is proven effective for remote monitoring, supports preventive maintenance strategies, and enhances the operational reliability of VRLA batteries in industrial environments.