Circuit Documentation

Summary

This circuit is designed to monitor and control an energy meter using an Arduino UNO microcontroller. It includes various components such as a relay, limit switch, buzzer, GSM module, LCD display, and more. The circuit can send SMS notifications and display information on an LCD screen. It also includes a safety feature to detect theft using a limit switch.

Component List

1. Arduino UNO

   • Description: A microcontroller board based on the ATmega328P.
   • Pins: UNUSED, IOREF, Reset, 3.3V, 5V, GND, Vin, A0, A1, A2, A3, A4, A5, SCL, SDA, AREF, D13, D12, D11, D10, D9, D8, D7, D6, D5, D4, D3, D2, D1, D0

2. 1-Channel Relay (5V 10A)

   • Description: A relay module that can control high voltage devices.
   • Pins: NC, signal, C, power, NO, ground

3. Limit Switch

   • Description: A switch that can detect physical limits or positions.
   • Pins: S, G, V

4. Buzzer

   • Description: An audio signaling device.
   • Pins: PIN, GND

5. 4N35

   • Description: An optocoupler for electrical isolation.
   • Pins: Anode, Cathode, NC, Base, Collector, Emitter

6. AC Bulb

   • Description: A standard AC light bulb.
   • Pins: P, N

7. SIM800L GSM Module

   • Description: A GSM module for sending and receiving SMS.
   • Pins: 5V, GND, VDD, SIM_TXD, SIM_RXD, RST

8. Resistor

   • Description: A 10k Ohm resistor.
   • Pins: pin1, pin2
   • Properties: Resistance: 10k Ohms

9. 16x2 I2C LCD

   • Description: A 16x2 character LCD with I2C interface.
   • Pins: GND, VCC, SDA, SCL

10. AC Supply

    • Description: An AC power supply.
    • Pins: +ve, -ve

11. LED: Two Pin (red)

    • Description: A red LED.
    • Pins: cathode, anode

Wiring Details

Arduino UNO

• 5V connected to:

  • 4N35 (Collector)
  • Limit Switch (S)
  • 16x2 I2C LCD (VCC)
  • 1-Channel Relay (power)

• GND connected to:

  • 16x2 I2C LCD (GND)
  • Limit Switch (G)
  • Resistor (pin2)
  • SIM800L GSM Module (GND)

• Vin connected to:

  • SIM800L GSM Module (5V)

• A0 connected to:

  • Limit Switch (V)

• A4 connected to:

  • 16x2 I2C LCD (SDA)

• A5 connected to:

  • 16x2 I2C LCD (SCL)

• D11 connected to:

  • SIM800L GSM Module (SIM_RXD)

• D10 connected to:

  • SIM800L GSM Module (SIM_TXD)

• D8 connected to:

  • 1-Channel Relay (signal)

• D7 connected to:

  • Buzzer (PIN)

• D2 connected to:

  • Resistor (pin1)
  • 4N35 (Emitter)

1-Channel Relay (5V 10A)

• NC connected to:

  • AC Bulb (P)

• C connected to:

  • AC Supply (+ve)

• ground connected to:

  • Buzzer (GND)

4N35

• Anode connected to:

  • LED: Two Pin (red) (anode)

• Cathode connected to:

  • LED: Two Pin (red) (cathode)

AC Bulb

• N connected to:
  • AC Supply (-ve)

Code Documentation

Arduino UNO Code

#include <EEPROM.h>
#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x27, 16, 2);

#include <SoftwareSerial.h>
SoftwareSerial GSM(10, 11);

#define buzzer 7
#define relay  8
#define bt_theft  A0

#define pulse_in 2

char inchar;

int unt_a = 0, unt_b = 0, unt_c = 0, unt_d = 0;
long total_unt = 7;

int price = 0;
long price1 = 0;

int Set = 10;

int pulse = 0;

String phone_no1 = "+919148487253";
String phone_no2 = "+919148314411";

int flag1 = 0, flag2 = 0, flag3 = 0;

void ai0() {
  // Your ISR code here
}

void initModule(const char* command, const char* response, unsigned long timeout) {
  // Your initModule code here
}

void sendSMS(String phoneNumber, String message) {
  // Your sendSMS code here
}

void Write() {
  // Your Write code here
}

void Read() {
  // Your Read code here
}

void load_on() {
  // Your load_on code here
}

void setup() {
  Serial.begin(9600);
  GSM.begin(9600);

  pinMode(bt_theft, INPUT_PULLUP);
  pinMode(relay, OUTPUT);
  pinMode(buzzer, OUTPUT);

  pinMode(pulse_in, INPUT);
  attachInterrupt(0, ai0, RISING);

  lcd.begin(16, 2); // Assuming a 16x2 LCD
  lcd.backlight();
  lcd.clear();
  lcd.setCursor(5, 0);
  lcd.print("WELCOME");
  lcd.setCursor(2, 1);
  lcd.print("Energy Meter");
  digitalWrite(buzzer, HIGH);

  Serial.println("Initializing....");
  initModule("AT", "OK", 1000);
  initModule("ATE1", "OK", 1000);
  initModule("AT+CPIN?", "READY", 1000);
  initModule("AT+CMGF=1", "OK", 1000);
  initModule("AT+CNMI=2,2,0,0,0", "OK", 1000);
  Serial.println("Initialized Successfully");
  delay(100);
  sendSMS(phone_no1, "Welcome To Energy Meter");
  digitalWrite(buzzer, LOW);
  lcd.clear();

  if (EEPROM.read(50) == 0) {}
  else {
    Write();
  }

  EEPROM.write(50, 0);

  pulse = EEPROM.read(10);

  Read();
  if (total_unt > 0) {
    digitalWrite(relay, HIGH);
  }
}

void loop() {
  if (GSM.available() > 0) {
    inchar = GSM.read();
    if (inchar == 'A') {
      delay(10);
      inchar = GSM.read();
      if (inchar == 'T') {
        delay(10);
        inchar = GSM.read();
        if (inchar == 'r') {
          delay(10);
          inchar = GSM.read();
          if (inchar == 'e') {
            delay(10);
            inchar = GSM.read();
            if (inchar == 'c') {
              delay(10);
              inchar = GSM.read();
              if (inchar == 'h') {
                delay(10);
                inchar = GSM.read();
                if (inchar == '1') {
                  price = 100 / Set;  total_unt = total_unt + price;
                  sendSMS(phone_no1, "Your Recharge is Done: 100");
                  sendSMS(phone_no2, "Your Recharge is Done: 100");
                  load_on();
                }
                else if (inchar == '2') {
                  price = 200 / Set;  total_unt = total_unt + price;
                  sendSMS(phone_no1, "Your Recharge is Done: 200");
                  sendSMS(phone_no2, "Your Recharge is Done: 200");
                  load_on();
                }
                else if (inchar == '3') {
                  price = 300 / Set;  total_unt = total_unt + price;
                  sendSMS(phone_no1, "Your Recharge is Done: 300");
                  sendSMS(phone_no2, "Your Recharge is Done: 300");
                  load_on();
                }
                else if (inchar == '4') {
                  price = 400 / Set;  total_unt = total_unt + price;
                  sendSMS(phone_no1, "Your Recharge is Done: 400");
                  sendSMS(phone_no2, "Your Recharge is Done: 400");
                  load_on();
                }
                delay(10);
              }
            }
          }