Complete Wiring Diagram

#include <WiFi.h>
#include <HTTPClient.h>
#include <ArduinoJson.h>
#include <PZEM004Tv30.h>

// WiFi credentials
const char* ssid = "YOUR_WIFI_SSID";
const char* password = "YOUR_WIFI_PASSWORD";

// API configuration
const char* apiUrl = "https://api.gridova.com/data";
const char* deviceId = "ROOM_001";

// Pin definitions
#define RELAY1_PIN 25
#define RELAY2_PIN 26

// Initialize PZEM sensor
PZEM004Tv30 pzem(Serial2, 16, 17);  // RX=16, TX=17

// Timing
unsigned long lastSendTime = 0;
const unsigned long sendInterval = 5000;  // 5 seconds

void setup() {
  Serial.begin(115200);
  Serial.println("Gridova System Starting...");
  
  // Initialize relay pins
  pinMode(RELAY1_PIN, OUTPUT);
  pinMode(RELAY2_PIN, OUTPUT);
  digitalWrite(RELAY1_PIN, HIGH);  // OFF (Active Low)
  digitalWrite(RELAY2_PIN, HIGH);  // OFF
  
  // Connect to WiFi
  WiFi.begin(ssid, password);
  Serial.print("Connecting to WiFi");
  
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  
  Serial.println("\nConnected!");
  Serial.print("IP Address: ");
  Serial.println(WiFi.localIP());
  
  // Test PZEM connection
  delay(1000);
  float voltage = pzem.voltage();
  if (!isnan(voltage)) {
    Serial.println("PZEM sensor OK");
  } else {
    Serial.println("PZEM sensor error!");
  }
  
  Serial.println("System ready!");
}

void loop() {
  unsigned long currentTime = millis();
  
  // Send data periodically
  if (currentTime - lastSendTime >= sendInterval) {
    readAndSendData();
    lastSendTime = currentTime;
  }
  
  // Check for relay commands
  checkRelayCommands();
  
  delay(100);
}

void readAndSendData() {
  // Read all PZEM values
  float voltage = pzem.voltage();
  float current = pzem.current();
  float power = pzem.power();
  float energy = pzem.energy();
  float frequency = pzem.frequency();
  float pf = pzem.pf();
  
  // Check if readings are valid
  if (isnan(voltage)) {
    Serial.println("Error reading PZEM sensor");
    return;
  }
  
  // Create JSON payload
  StaticJsonDocument<512> doc;
  doc["device_id"] = deviceId;
  doc["timestamp"] = millis();
  
  JsonObject data = doc.createNestedObject("sensor_data");
  data["voltage"] = voltage;
  data["current"] = current;
  data["power"] = power;
  data["energy"] = energy;
  data["frequency"] = frequency;
  data["power_factor"] = pf;
  
  JsonObject relayStatus = doc.createNestedObject("relay_status");
  relayStatus["relay1"] = (digitalRead(RELAY1_PIN) == LOW);
  relayStatus["relay2"] = (digitalRead(RELAY2_PIN) == LOW);
  
  String jsonString;
  serializeJson(doc, jsonString);
  
  // Send to server
  if (WiFi.status() == WL_CONNECTED) {
    HTTPClient http;
    http.begin(apiUrl);
    http.addHeader("Content-Type", "application/json");
    
    int httpCode = http.POST(jsonString);
    
    if (httpCode > 0) {
      Serial.printf("✓ Data sent (HTTP %d)\n", httpCode);
    } else {
      Serial.printf("✗ Send failed: %s\n", 
                    http.errorToString(httpCode).c_str());
    }
    
    http.end();
  }
  
  // Display readings
  Serial.println("\n========== Readings ==========");
  Serial.printf("Voltage:  %.2f V\n", voltage);
  Serial.printf("Current:  %.3f A\n", current);
  Serial.printf("Power:    %.2f W\n", power);
  Serial.printf("Energy:   %.3f kWh\n", energy);
  Serial.printf("Frequency: %.1f Hz\n", frequency);
  Serial.printf("PF:       %.2f\n", pf);
  Serial.printf("Relay1:   %s\n", 
                digitalRead(RELAY1_PIN) == LOW ? "ON" : "OFF");
  Serial.printf("Relay2:   %s\n", 
                digitalRead(RELAY2_PIN) == LOW ? "ON" : "OFF");
  Serial.println("=============================\n");
}

void checkRelayCommands() {
  if (WiFi.status() != WL_CONNECTED) return;
  
  HTTPClient http;
  String url = String(apiUrl) + "/relay/status?device_id=" + deviceId;
  
  http.begin(url);
  int httpCode = http.GET();
  
  if (httpCode == 200) {
    String payload = http.getString();
    
    StaticJsonDocument<256> doc;
    DeserializationError error = deserializeJson(doc, payload);
    
    if (!error) {
      bool relay1Cmd = doc["relay1"];
      bool relay2Cmd = doc["relay2"];
      
      // Update relay states
      digitalWrite(RELAY1_PIN, relay1Cmd ? LOW : HIGH);
      digitalWrite(RELAY2_PIN, relay2Cmd ? LOW : HIGH);
    }
  }
  
  http.end();
}

// Emergency shutoff function
void emergencyShutoff() {
  digitalWrite(RELAY1_PIN, HIGH);  // OFF
  digitalWrite(RELAY2_PIN, HIGH);  // OFF
  Serial.println("EMERGENCY SHUTOFF ACTIVATED!");
}