Abstract
This paper presents a portable, customized low-cost data acquisition system using the ESP32-C6 microcontroller and the INA219 sensor. The use of traditional multi-meters is time-consuming and subject to human error, especially for experiments with longer durations,which require continuous logging and repeated readings. Manual data recording increases the risk of transcription mistakes and limits sampling resolution. Since DC systems have gained significant attention in recent years across renewable energy and IoT applications, the need for more accurate, automated DC power acquisition is increasingly critical. We conduct a comparative analysis of the INA219 sensor under low and elevated voltage applications to evaluate the accuracy of the INA219 sensor with the calibrated reference DC power supply. Our experiment indicates perfect linear correlation between power and current in both modes (r≈1.000 for low-power, r = 0.992 for high-power) applications, respectively. A Python-based application was developed to assess the data logging ability of the COOLTERM software. This application will perform statistical analysis of the time-series power measurement datasets, including a visual representation in graphical form to clearly display the energy trend in the DC power system. This system provides a practical solution for real-time power measurement across a variety of DC systems, including IoT applications, solar renewable energy, laboratory experimentation, and related DC power systems.
Keywords
ESP32‑C6 microcontroller
INA219 current sensor
Portable data acquisition
Python-based application
Real‑time power monitor