IoT Smart Energy Meter Using ESP8266 & PZEM-004T Module | Voltage & Current Protection

Build a complete IoT Smart Energy Meter Using ESP8266 and PZEM‑004T v3.0 with professional voltage/current protections, automatic relay cut‑off, dual 20×4 I2C LCD pages, and a beautiful violet/dark animated Web UI. Learn wiring, code, thresholds (OV/UV/OC), JSON API, and how to fix LCD “random characters” and stale readings by full‑line rendering and safe NaN handling. Perfect for home and lab monitoring. 📌 Written Tutorial: https://circuitdiagrams.in/iot-smart-... 📌 Code & Circuit Diagram: https://circuitdiagrams.in/shop/smart... What you’ll learn: ✅ Hardware: ESP8266 (NodeMCU), PZEM‑004T v3.0, low‑trigger SSR, 20×4 I2C LCD, page button ✅ Protections: Over Voltage, Under Voltage, Over Current with auto relay cut (manual/auto modes, latching) ✅ Web Dashboard: Live readings, manual controls, thresholds with persistence, animated AC mains indicator ✅ Code Quality: Two‑decimal formatting, units after values, null-safe JSON, robust LCD padding to prevent artifacts ✅Troubleshooting: Clear stale values on mains loss, fix LCD artifacts, avoid NaN in JSON 🔧 Components Used: ESP8266 NodeMCU Board: https://amzn.to/4nOcl8w DC to DC Step Down Module: https://amzn.to/4425jWm 20x4LCD Display (I2C Module): https://amzn.to/4hWrtiK PZEM-004T Sensor: https://amzn.to/3WOyiZX 5V Relay Module: https://amzn.to/4qXIBc8 Veroboard: https://amzn.to/487liF6 📸 Gear Used: Camera: Sony Alpha ZV-E10M2K (16-50mm Power Zoom Lens) [https://amzn.to/4rePypn] Tripod: DIGITEK DPTR 895VD [https://amzn.to/42y7Cjd] 📌 Chapters 00:00 – Intro & demo 00:37 – Custom Project 00:54 – Components Required 02:58 – Wiring (ESP8266, PZEM‑004T, SSR, LCD) 07:03 – Testing Our System 10:09 – Protections (OV/UV/OC) and auto cut logic 12:50 – High Load Testing 14:03 – Outro 👉 If you enjoy IoT, ESP32, and Arduino projects, don’t forget to Like 👍, Share ↗️, and Subscribe 🔔 to Circuit Diagrams for more tutorials! 📱 Connect & Follow: 🌐 Website: https://www.circuitdiagrams.in 🐙 GitHub: https://github.com/tanmoykundu80 📘 Facebook:   / circuitdiagrams.in   📸 Instagram:   / circuitdiagrams   📌 Pinterest:   / creativescanner8481   ✉️ Email: [email protected] 📌Hashtags: #ESP8266 #PZEM004T #SmartIoTEnergyMeter #IoTACEnergyMeter #IoTEnergyMeter #EnergyMeter #IOTProjects #ArduinoIDE #SmartHome #ElectronicsProjects #DIYElectronics #ESP32Projects #overvoltageprotection #undervoltageprotection #overcurrentprotection #voltagecurrentprotectionsystem