IoT Energy Meter With Protections Using PZEM-004T Source Code With Project Report

Description

This source code implements a complete, production-ready Smart IoT Energy Meter built around the PZEM004T v3 energy monitoring module. It is designed for real-world AC load monitoring, protection, and remote control through a modern web dashboard, while also providing clear local feedback on a 20×4 I2C LCD.

Components Required

• ESP8266 NodeMCU Board / ESP32 Dev Board
• PZEM-004T Version 3.0 or 4.0
• 20×4 I2C LCD Display (SDA, SCL Enabled)
• 5V/10A 2 Channel Relay Module
• 5V DC Adapter
• Push Button
• AC Socket (as load)
• 1.5sqmm Electrical Wires

Demo Dashboard

Files You Will Get

🔹 Specifications

Real-Time Electrical Measurement

• Accurate Voltage (V), Current (A), Power (W), Energy (kWh) readings from PZEM004T
• Displays Power Factor (PF) and Frequency (Hz)
• Automatic handling of invalid or disconnected mains states

Smart Protection System

• Over-Voltage Protection
• Under-Voltage Protection
• Over-Current Protection
• Automatic relay cutoff with clear fault reason (e.g., Over Voltage, Disconnected)

Relay Control

• Supports Active-LOW relay
• Three operating modes:
  • AUTO – Smart protection enabled
  • MANUAL ON
  • MANUAL OFF
• Relay state automatically restored after reboot

Non-Volatile Configuration

• Uses LittleFS to store:
  • Voltage & current thresholds
  • Relay operating mode
• Settings persist even after power loss or reset

🌐 Built-In Web Dashboard

• Responsive, mobile-friendly UI
• Live values update automatically (AJAX/JSON based)
• Animated AC mains ON/OFF indicator
• One-click relay control (ON / OFF / AUTO)
• Adjustable protection thresholds directly from browser
• Clean API endpoints for integration with apps or cloud services

🖥️ Local Display & Controls

• 20×4 I2C LCD shows:
  • Page 1: Voltage, Current, Power, System Status
  • Page 2: Energy, PF, Frequency, Mode & Thresholds
• Single button to switch display pages
• Clear startup messages for WiFi / AP mode and IP address

📡 WiFi & Network Behavior

• Connects automatically to configured WiFi network
• If WiFi fails, device starts its own Access Point (AP mode)
• Dashboard accessible via local IP – no cloud dependency

🧠 Software Architecture Highlights

• Clean modular structure (Protection, Web, LCD, Config)
• JSON-based API for easy extension
• Interrupt-based button handling with debounce
• Safe relay logic prevents energizing load during fault conditions

🔌 Typical Applications

• Home or industrial smart energy meters
• AC load protection & monitoring panels
• IoT-based power consumption logging
• Smart distribution boards
• DIY or commercial automation projects

📦 What You Get (Source Code)

• Fully commented ESP8266 source code
• All Libraries
• Circuit Schematic
• Demo HTML Dashboard
• Project Report (PDF)
• Presentation PPT
• Wiring Guide (PDF)
• Webdashboard Operation Guide (PDF)
• Wiring Guide (PDF)
• Troubleshooting Guide (PDF)

⚠️ Important Notes

• Designed for PZEM004T v3.0 and v4.0 (UART version)
• Use proper electrical isolation and safety precautions
• Relay must be rated for target AC load