IoT-Enabled Smart Energy Meter with SMS Alerts

10 Pc. Jumper Wire Kit, 20 cm Long

Arduino IDE

Breadboard, 170 Pin

LCD 16X2

Arduino Nano ESP32 Connector Bundle

<html><body><h3>Project Overview</h3>This project builds a <a href="https://circuitdigest.com/microcontroller-projects/iot-based-smart-energy-meter-with-sms-alert">smart energy meter using IoT </a>that tracks key electrical parameters and alerts you when abnormal conditions are detected. It uses an ESP32 microcontroller, a PZEM-004T sensor module, and MQTT to send real-time measurements like voltage, current, power, and energy to an online dashboard. If a parameter crosses a set threshold (e.g., high voltage), the system sends an SMS alert to your phone using a cloud API. <figure><img src="https://projects.arduinocontent.cc/60db5cba-4e84-44bc-bce5-6e0f11ada31e.jpg"/><figcaption>Smart Energy Meter Using IoT</figcaption></figure> <h3>What You’ll Build</h3>A compact energy monitoring system that: <ol><li>Measures electrical parameters using a PZEM-004T module. </li><li>Displays readings locally on a 16×2 I2C LCD. </li><li>Publishes data to a remote MQTT dashboard over Wi-Fi. </li><li>Sends SMS alerts for abnormal conditions (e.g., high voltage) via a cloud SMS API. </li></ol> <figure><img src="https://projects.arduinocontent.cc/45c12e30-cec8-4932-8c09-d688edb28a1e.jpg"/><figcaption>Dashboard Smart Energy Meter Using IoT</figcaption></figure> <h3>How It Works</h3>Sensing: The PZEM-004T module connects in series with the AC mains and measures voltage, current, active power, energy, frequency and power factor. Communication: The ESP32 reads those values over UART (Modbus) and shows them on the LCD. IoT Dashboard: The ESP32 publishes readings over Wi-Fi to an MQTT broker so you can monitor them in real time on any device. Alerting: When a reading crosses a defined threshold (e.g., voltage too high), the ESP32 makes an HTTP request to a cloud SMS service, sending an alert to your registered number. <figure><img src="https://projects.arduinocontent.cc/0b3dd0a4-bff2-4d36-b578-0bf915c7d53f.jpg"/><figcaption>Block diagram Smart Energy Meter Using IoT</figcaption></figure> <h3>Circuit Summary</h3>PZEM-004T TX → ESP32 RX2 (GPIO16) PZEM-004T RX → ESP32 TX2 (GPIO17) LCD SDA → ESP32 GPIO21 LCD SCL → ESP32 GPIO22 5V &amp; GND to components <figure><img src="https://projects.arduinocontent.cc/06615146-3d8b-44de-8603-c23271d5aee9.jpg"/><figcaption>Circuit diagram of Smart Energy Meter Using IoT</figcaption></figure> <h3>Key Software Features</h3><ol><li>Wi-Fi + MQTT: Connects to a Wi-Fi network and publishes sensor data to a broker. </li><li>Secure SMS Calls: Uses HTTPS to trigger SMS alerts when parameters exceed limits. </li><li>LCD Cycling: Displays voltage, current, power, etc., in a loop on the LCD. </li></ol> Example Alert Logic (Pseudocode) <pre>float voltage = pzem.voltage(); </pre><pre>if (voltage &gt; threshold &amp;&amp; millis() - lastSMS &gt; cooldown) { </pre><pre>	 sendSMSAlert(); </pre><pre>	 lastSMS = millis(); </pre><pre>} </pre> This ensures alerts are not spammed and only trigger once per set interval. What You’ll Learn Integrating energy measurement hardware with a microcontroller. Reading and publishing real-time sensor data over MQTT. Sending SMS alerts using secure HTTP APIs. Building a multi-interface monitoring system combining local and remote views. <h3>Applications</h3>Remote household energy tracking. Early warning for electrical issues like voltage spikes. Integration with home automation systems using MQTT. Safety Notes The PZEM-004T isolates the ESP32 from mains, but always follow safety practices when working with AC power. <figure><iframe src="https://youtu.be/bQ4-pWsC5WA"></iframe></figure></body></html>

IoT-Enabled Smart Energy Meter with SMS Alerts

Monitor mains voltage, current, power and energy remotely via MQTT with ESP32 and get SMS alerts for abnormal conditions like high voltage.