Creating a Smart AC Meter with the Arduino Uno R4 WiFi, ZMPT101B for voltage, ACS712-20A for current measurement, and DHT22 for humidity and temperature with features and capabilities like:
Voltage Measurement: Accurate AC voltage measurement using ZMPT101B.
Current Measurement: Monitor current draw with ACS712-20A.
Power Calculation: Compute real-time power (W), energy consumption (kWh), and power factor.
Temperature & Humidity Monitoring: Track environmental data with DHT22.
Data Logging: Store historical data on a microSD card or in EEPROM.
MQTT Data Upload: Send data to an MQTT broker for real-time analysis and remote monitoring.
Web Dashboard: Create a simple web interface for local monitoring and control.
Overload Protection: Implement logic to trigger alarms or cut-off circuits if current or voltage exceeds thresholds.
OTA Updates: Update firmware over WiFi to add features or fix bugs.
Mobile Alerts: Send push notifications or emails for alerts or abnormal readings.

The Arduino Uno R4 WiFi is best suited for this project as it has features like:
Built-in WiFi and Bluetooth (ESP32-S3-MINI): Enables wireless communication, ideal for MQTT data upload and remote monitoring/control.
Improved Processing Power: With a 32-bit Renesas RA4M1 microcontroller, it offers more processing power for handling complex tasks, including real-time data logging and environmental monitoring.
Additional GPIO Pins: Provides more flexibility in connecting sensors like ZMPT101B, ACS712, and DHT22.
USB-C Interface: Faster data transfer and easier connection for firmware updates.
Enhanced Memory: More SRAM and Flash memory allow for larger, more complex code and data handling.
Onboard RTC: Useful for timestamping data, especially for energy monitoring over time.
It also features ADC (Analog-to-Digital Converter) with a resolution of 14 bits, providing higher precision for analog sensor readings, like those from the ZMPT101B and ACS712 sensors