Smart Grid Monitor Using Arduino UNO R4 WiFi

Breadboard - 400 contacts

Arduino USB 2.0 CABLE TYPE A/B 1M

Grove - OLED Display 0.96"

Arduino® UNO R4 WiFi

10 jumper wires 150mm male

Arduino IDE

fritzing

<html><body><h3>Introduction</h3>Monitoring electricity usage in real time is becoming increasingly important for homes, workshops, laboratories, and small industrial environments. Instead of waiting for monthly utility bills, a smart monitoring system can continuously track power consumption, identify unusual behavior, and provide valuable insights into energy usage patterns.In this project, I built a Smart Grid Monitoring System using the Arduino UNO R4 WiFi and the PZEM-004T energy meter. The system measures voltage, current, power, energy consumption, frequency, and power factor in real time. The collected data is displayed locally on an OLED screen and simultaneously uploaded to ThingSpeak for remote monitoring and historical analysis.The project combines energy measurement, embedded programming, wireless communication, and cloud-based visualization into a compact and practical IoT solution.<figure><img src="https://projects.arduinocontent.cc/ffaef8e5-c132-4065-99b7-d5363e69742e.jpg"/><figcaption></figcaption></figure><h3>Features</h3><ol><li>Real-time voltage monitoring</li><li>Current measurement using a non-invasive current transformer</li><li>Active power calculation</li><li>Energy consumption tracking</li><li>Frequency measurement</li><li>Power factor monitoring</li><li>OLED display for local visualization</li><li>WiFi-based cloud logging</li><li>ThingSpeak dashboard integration</li></ol>Expandable architecture for future smart-grid applications<h3>How the System Works</h3>The PZEM-004T energy meter continuously measures electrical parameters from the connected AC line. Voltage is measured directly through the module, while current is sensed using the included current transformer clamp.The PZEM processes these measurements internally and calculates:<ol><li>Voltage (V)</li><li>Current (A)</li><li>Power (W)</li><li>Energy (kWh)</li><li>Frequency (Hz)</li><li>Power Factor (PF)</li></ol>The Arduino UNO R4 WiFi communicates with the PZEM module through Modbus RTU over UART. It requests the latest measurements at regular intervals and stores them in memory.Once the data is received:<ol><li>The OLED display is updated with the latest readings.</li><li>Values are printed to the Serial Monitor for debugging.</li><li>The data is sent to ThingSpeak through the onboard WiFi connection.</li><li>ThingSpeak stores the readings and generates graphs automatically.</li></ol>This creates a complete monitoring loop that provides both local and remote visibility of power usage.<figure><img src="https://projects.arduinocontent.cc/e21a4f53-bbc9-467d-b893-8bc2352bcd3a.jpg"/><figcaption></figcaption></figure><h3>Why Use Arduino UNO R4 WiFi?</h3>The Arduino UNO R4 WiFi is an excellent choice for IoT monitoring applications because it combines a powerful 32-bit microcontroller with built-in wireless connectivity.<h3>Advantages include:</h3><ol><li>Integrated WiFi support</li><li>Reliable hardware serial communication</li><li>Increased processing capability compared to previous UNO boards</li><li>Easy cloud connectivity</li><li>Large ecosystem of Arduino libraries</li></ol>These features make it ideal for energy monitoring and smart-grid experimentation.<h3>Components Required</h3><ol><li>Arduino UNO R4 WiFi</li><li>PZEM-004T Energy Meter</li><li>Current Transformer Clamp</li><li>128×64 I2C OLED Display</li><li>Push Button</li><li>Jumper Wires</li><li>Breadboard or PCB</li><li>USB Cable</li><li>AC Load for testing</li></ol><figure><img src="https://projects.arduinocontent.cc/3fd5ce50-57e3-4020-bf9a-51c1073d4138.jpg"/><figcaption></figcaption></figure><h3>Connections</h3>PZEM-004T to Arduino UNO R4 WiFiTX → Pin 0 (RX)RX → Pin 1 (TX)VCC → 5VGND → GNDOLED DisplaySDA → A4SCL → A5VCC → 5VGND → GNDPush ButtonOne side → Digital Pin 7Other side → GNDThe button can be used to switch display screens or enable different viewing modes.<figure><img src="https://projects.arduinocontent.cc/a461b11a-a9f4-4747-abf7-5164df58b45c.jpg"/><figcaption></figcaption></figure><h3>Cloud Integration with ThingSpeak</h3>ThingSpeak provides a simple way to store and visualize sensor data.Create a free ThingSpeak account and generate a new channel with fields for:<ol><li>Voltage</li><li>Current</li><li>Power</li><li>Energy</li><li>Frequency</li><li>Power Factor</li></ol>After creating the channel, copy the Channel ID and Write API Key into the Arduino sketch.Once uploaded, the board automatically sends measurements to the cloud at regular intervals.The dashboard then generates graphs that help visualize power usage trends over time.<figure><img src="https://projects.arduinocontent.cc/13e7bf87-5da8-441b-aed5-e8e0db3ed2f1.jpg"/><figcaption></figcaption></figure><h3>Software Overview</h3>The firmware is organised into three main tasks:Data AcquisitionThe Arduino requests measurements from the PZEM module through Modbus communication and stores the received values.Local DisplayThe OLED screen continuously updates to show the latest electrical parameters, allowing immediate access to live readings.Cloud UploadThe measured values are assigned to ThingSpeak fields and transmitted through WiFi for long-term storage and visualization.Separating these functions keeps the code easy to maintain and simplifies troubleshooting.<h3>Applications</h3>This project can be adapted for many real-world uses:<ol><li>Home energy monitoring</li><li>Smart building systems</li><li>Laboratory testing</li><li>Workshop power analysis</li><li>Renewable energy monitoring</li><li>Educational demonstrations</li><li>Appliance energy tracking</li><li>Load profiling and diagnostics</li></ol><h3>Future Improvements</h3>The modular design makes it easy to expand the system further.Possible upgrades include:<ol><li>SD card data logging</li><li>Multiple PZEM modules for multi-circuit monitoring</li><li>Mobile notifications</li><li>Overcurrent alerts</li><li>Overvoltage protection warnings</li><li>Web dashboard hosting</li><li>Daily and monthly energy reports</li><li>Predictive maintenance analytics</li></ol><h3>Results</h3>The system successfully measures electrical parameters in real time and uploads them to the cloud for remote access.The OLED display provides immediate local feedback, while ThingSpeak enables historical tracking and graphical analysis from anywhere with an internet connection.The combination of local monitoring and cloud-based visualization transforms a simple energy meter into a practical smart-grid node that can be used for learning, experimentation, and small-scale deployment.<h3>Conclusion</h3>This <a href="https://circuitdigest.com/microcontroller-projects/smart-grid-iot-using-arduino-uno-r4">Smart grid in IoT</a> project demonstrates how to build a practical IoT-based smart energy monitoring system using the Arduino UNO R4 WiFi and the PZEM-004T energy meter.By combining real-time sensing, local visualization, and cloud connectivity, the system provides valuable insight into electrical consumption and power quality. It is easy to build, highly expandable, and serves as an excellent introduction to smart-grid concepts, embedded systems, and IoT-based energy analytics.Whether you are a student, maker, or engineer, this project provides a strong foundation for developing more advanced energy management and monitoring solutions.Build innovative Arduino, ESP32, IoT, robotics, home automation, and smart electronics projects with complete circuit diagrams, source code, and step-by-step tutorials for makers, students, and engineers.Explore a wide range of innovative DIY electronics and maker tutorials in the <a href="https://circuitdigest.com/arduino-projects">Arduino Projects</a> Collection by CircuitDigest<figure><iframe src="https://youtu.be/Sy0ap-J-04A?si=a1tO4gX63p5l6AGg"></iframe></figure></body></html>

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Smart Grid Monitor Using Arduino UNO R4 WiFi

Real-time energy monitoring with cloud logging, OLED display, and IoT analytics