Microcontroller Based Voltage Monitoring and Load Control with Over/Under Voltage Protection

Abstract

The stability of electrical power supply is critical for the reliable operation of household and industrial appliances. Variations in voltage, such as over voltage and under voltage, can cause severe damage to sensitive loads, reduce equipment lifespan, and create safety hazard. To address this issue, an Microcontroller Based Voltage Monitoring and Load Control with Over/Under Voltage Protection. The system continuously monitors the input supply voltage through a voltage sensor and compares with predefined safe operating limits. If the voltage exceeds the upper threshold over voltage or falls below the lower threshold under voltage, the ESP32 triggers a relay to disconnect the load, thereby preventing damage. A buzzer provides an audio alert, while an LCD display or mobile interface via Wi- Fi Shows real- time voltage levels any system status. Once the voltage returns to normal limits, the ESP32 automatically reconnects the load, ensuring uninterrupted and safe operation. This intelligent protection system offers fast response, low cost, and flexibility, making it suitable for residential, commercial, and industrial applications.