Building 3-Phase AC Power Meter with ESP01

Building a 3-Phase AC Power Meter using ESP01 and PZEM004T v3

In this article, we will explore the process of building a 3-phase AC power meter using an ESP01 module and a PZEM004T v3 AC power monitoring module. The project utilizes the Tasmota firmware and can measure currents up to 100A and voltages up to 260V AC.

Introduction

The project described here is a 3-phase AC power meter that uses an ESP01 module as the brain of the operation and a PZEM004T v3 AC power monitoring module for measuring electrical parameters. This is the second iteration of the design, with plenty of room for improvement.

Components Used

• ESP01 module
• PZEM004T v3 AC power monitoring module
• Tasmota firmware
• I2C port for adding a display or other I2C devices
• MQTT broker for integration with home assistants

PCB Fabrication

The PCB boards were ordered from NextPCB, and they arrived after a 10-day wait. The quality of the PCBs is impressive, as expected.

Assembly

All the necessary components were gathered, and the board was soldered together. After assembly, the board looks neat and tidy.

Firmware Flashing

A USB to TTL module was used to flash the Tasmota firmware onto the ESP01 module. The process is straightforward, with detailed steps available on the Tasmota web installer website.

Features and Capabilities

• Measures currents up to 100A using a 100A ZT
• Measures voltages up to 260V AC
• I2C port for adding a display or other I2C devices
• MQTT broker for integration with home assistants

Purchasing Information

For those interested in purchasing this power meter or other products, please contact the author via Instagram. The link to the author's Instagram account is provided below.

Conclusion

This article has detailed the process of building a 3-phase AC power meter using an ESP01 module and a PZEM004T v3 AC power monitoring module. With its impressive feature set and capabilities, this project is sure to be of interest to those looking for a DIY solution for monitoring electrical parameters.

const int ct1 = A0; // CT for phase 1
const int ct2 = A1; // CT for phase 2
const int ct3 = A2; // CT for phase 3

void setup() {
  Serial.begin(9600);
  pinMode(ct1, INPUT);
  pinMode(ct2, INPUT);
  pinMode(ct3, INPUT);
}

void loop() {
  int rawValue1 = analogRead(ct1);
  int rawValue2 = analogRead(ct2);
  int rawValue3 = analogRead(ct3);

  // Calculate current values using CT calibration data
  float current1 = (rawValue1 * 5.0) / 1024.0;
  float current2 = (rawValue2 * 5.0) / 1024.0;
  float current3 = (rawValue3 * 5.0) / 1024.0;

  // Calculate power values using voltage and current
  float power1 = calculatePower(current1, 230.0); // assuming 230V phase-to-neutral voltage
  float power2 = calculatePower(current2, 230.0);
  float power3 = calculatePower(current3, 230.0);

  Serial.print("Phase 1 Power: ");
  Serial.println(power1);
  Serial.print("Phase 2 Power: ");
  Serial.println(power2);
  Serial.print("Phase 3 Power: ");
  Serial.println(power3);

  delay(1000); // update every 1 second
}

• Processor: Tensilica L106 32-bit RISC CPU
• Flash Memory: 4MB
• SRAM: 96KB
• Wi-Fi: IEEE 802.11b/g/n
• Operating Voltage: 3.3V

• Measuring Range: ±5A, ±20A, ±30A (depending on model)
• Sensitivity: 66mV/A, 100mV/A, or 185mV/A (depending on model)
• Output Type: Analog

• Measuring Range: 0-400V AC
• Sensitivity: 1V/V (100mV output for every 1V input)
• Output Type: Analog

• Input Voltage Range: 220-240V AC (depending on model)
• Output Voltage: 3.3V DC
• Output Current: up to 2A (depending on model)

• Turn Ratio: varies depending on model (e.g., 1000:1, 2000:1)
• Operating Frequency Range: 50-60 Hz

• Resistance Value: typically 1kΩ or 2.5kΩ (depending on model)
• Power Rating: varies depending on application

• Programming Language: C/C++
• Library and Framework: Arduino Core for ESP8266/ESP32 or ESP IDF