How to Use PZEM-04T: Examples, Pinouts, and Specs

The PZEM-04T is a multifunctional electrical parameter measurement module designed to measure voltage, current, power, and energy. This versatile module is widely used in energy monitoring and management systems, providing accurate and real-time data for various applications. Whether you are working on a home automation project, industrial energy management, or renewable energy systems, the PZEM-04T offers a reliable solution for monitoring electrical parameters.

1. Power Supply: Connect the VCC pin to a 5V DC power supply and the GND pin to the ground.
2. Voltage Measurement: Connect the A and B pins to the live and neutral wires of the AC voltage you want to measure.
3. Current Measurement: Connect the external current transformer (CT) to the CT pin. Ensure the CT is properly clamped around the live wire of the AC circuit.
4. Communication: Connect the RX and TX pins to the corresponding UART pins of your microcontroller (e.g., Arduino UNO).

• Safety First: Always ensure the module is powered off before making any connections to avoid electric shock.
• Proper Clamping: Ensure the current transformer is securely clamped around the live wire for accurate current measurement.
• Stable Power Supply: Use a stable 5V DC power supply to avoid fluctuations in readings.
• Isolation: If necessary, use optocouplers or isolation circuits to protect your microcontroller from high voltage.

#include <SoftwareSerial.h>

// Define the RX and TX pins for SoftwareSerial
SoftwareSerial pzem(10, 11); // RX, TX

void setup() {
  Serial.begin(9600); // Initialize serial communication at 9600 baud
  pzem.begin(9600);   // Initialize PZEM communication at 9600 baud
}

void loop() {
  // Request data from PZEM-04T
  pzem.write(0xB0); // Command to read voltage
  delay(100);       // Wait for the response

  if (pzem.available()) {
    // Read the response
    byte response[7];
    for (int i = 0; i < 7; i++) {
      response[i] = pzem.read();
    }

    // Extract voltage value from the response
    float voltage = (response[2] << 8 | response[3]) / 10.0;

    // Print the voltage value to the serial monitor
    Serial.print("Voltage: ");
    Serial.print(voltage);
    Serial.println(" V");
  }

  delay(1000); // Wait for 1 second before the next reading
}

1. No Data Received: Ensure the RX and TX pins are correctly connected and the baud rate matches.
2. Inaccurate Readings: Verify the current transformer is properly clamped and the module is powered by a stable 5V DC supply.
3. Module Not Responding: Check all connections and ensure the module is not damaged.

• Check Connections: Double-check all wiring and connections to ensure they are secure and correct.
• Use a Stable Power Supply: Ensure the power supply is stable and within the specified range.
• Verify Baud Rate: Ensure the baud rate for communication matches the module's default (9600 baud).
• Inspect the CT: Make sure the current transformer is properly clamped around the live wire and not damaged.

By following this documentation, you should be able to effectively integrate and use the PZEM-04T module in your projects, ensuring accurate and reliable electrical parameter measurements.