Project Documentation

ESP32-Based Smart Water Quality Monitoring System with TCS3200 Color Sensor and Wi-Fi Connectivity

Circuit Documentation

Summary

This circuit utilizes an ESP32 microcontroller to interface with various sensors and LEDs. The ESP32 reads data from a TCS3200 color sensor, a TDS sensor, and a pH sensor. It also controls three LEDs (red, green, and yellow) to indicate different statuses. The data collected from the sensors is sent to ThingSpeak for remote monitoring.

Component List

ESP32 (30 pin)
- Description: A powerful microcontroller with WiFi and Bluetooth capabilities.
- Pins: EN, VP, VN, D34, D35, D32, D33, D25, D26, D27, D14, D12, D13, GND, Vin, D23, D22, TX0, RX0, D21, D19, D18, D5, TX2, RX2, D4, D2, D15, 3V3
TCS3200
- Description: A color sensor that can detect and measure the intensity of red, green, and blue light.
- Pins: GND, OUT, S2, S3, VCC, LED, S0, S1
Resistor (200 Ohms)
- Description: A resistor with a resistance of 200 Ohms.
- Pins: pin1, pin2
LED: Two Pin (red)
- Description: A red LED.
- Pins: cathode, anode
LED: Two Pin (green)
- Description: A green LED.
- Pins: cathode, anode
LED: Two Pin (yellow)
- Description: A yellow LED.
- Pins: cathode, anode
TDS Sensor 2
- Description: A sensor used to measure the Total Dissolved Solids (TDS) in water.
- Pins: AIn, GND, 5V
pH Sensor (ph4502c)
- Description: A sensor used to measure the pH level of a solution.
- Pins: VCC, G1, G2, Po, Do, To
7.4v Battery
- Description: A 7.4V power source.
- Pins: +, -

Wiring Details

ESP32 (30 pin)

GND: Connected to the GND pins of the red, green, and yellow LEDs, TCS3200, TDS Sensor 2, and pH sensor.
D13: Connected to the anode of the red LED through a 200 Ohm resistor.
D12: Connected to the anode of the green LED through a 200 Ohm resistor.
Vin: Connected to the + pin of the 7.4v battery and the VCC and LED pins of the TCS3200.
3V3: Connected to the VCC pin of the pH sensor and the 5V pin of the TDS Sensor 2.
D34: Connected to the AIn pin of the TDS Sensor 2.
D27: Connected to the Po pin of the pH sensor.
D14: Connected to the OUT pin of the TCS3200.
D21: Connected to the S1 pin of the TCS3200.
D19: Connected to the S3 pin of the TCS3200.
D18: Connected to the S2 pin of the TCS3200.
D5: Connected to the S0 pin of the TCS3200.

TCS3200

GND: Connected to the GND pin of the ESP32.
OUT: Connected to the D14 pin of the ESP32.
S2: Connected to the D18 pin of the ESP32.
S3: Connected to the D19 pin of the ESP32.
VCC: Connected to the Vin pin of the ESP32.
LED: Connected to the Vin pin of the ESP32.
S0: Connected to the D5 pin of the ESP32.
S1: Connected to the D21 pin of the ESP32.

Resistor (200 Ohms)

pin1: Connected to the anode of the red LED.
pin2: Connected to the D13 pin of the ESP32.

LED: Two Pin (red)

cathode: Connected to the GND pin of the ESP32.
anode: Connected to the pin1 of the 200 Ohm resistor.

LED: Two Pin (green)

cathode: Connected to the GND pin of the ESP32.
anode: Connected to the pin1 of the 200 Ohm resistor.

LED: Two Pin (yellow)

cathode: Connected to the GND pin of the ESP32.
anode: Connected to the pin1 of the 200 Ohm resistor.

TDS Sensor 2

AIn: Connected to the D34 pin of the ESP32.
GND: Connected to the GND pin of the ESP32.
5V: Connected to the 3V3 pin of the ESP32.

pH Sensor (ph4502c)

VCC: Connected to the 3V3 pin of the ESP32.
G1: Connected to the GND pin of the ESP32.
G2: Connected to the GND pin of the ESP32.
Po: Connected to the D27 pin of the ESP32.

7.4v Battery

+: Connected to the Vin pin of the ESP32.
-: Connected to the GND pin of the ESP32.

Documented Code

/*
  ESP32 TCS3200 Color sensor
  http:://www.electronicwings.com
*/
#include <WiFi.h>
#include "ThingSpeak.h"
#define S0 5
#define S1 21
#define S2 18          /*Define S2 Pin Number of ESP32*/
#define S3 19          /*Define S3 Pin Number of ESP32*/
#define sensorOut 14  /*Define Sensor Output Pin Number of ESP32*/
#define LED_PIN 13
#define LED_PIN_1 12
#define TdsSensorPin 34  // Analog pin for the TDS sensor (use a valid ADC pin on ESP32)
#define VREF 3.3         // Analog reference voltage (Volt) of the ESP32 ADC
#define SCOUNT 30        // Number of samples for averaging

const char* ssid = "Neero3110";   // your network SSID (name) 
const char* password = "123123123";   // your network password

WiFiClient  client;

unsigned long myChannelNumber = 1;
const char * myWriteAPIKey = "P8Q9DC7AFSFYNZX9";
unsigned long lastTime = 0;
unsigned long timerDelay = 30000;

int analogBuffer[SCOUNT];          // Store the analog values in an array
int analogBufferTemp[SCOUNT];      // Temporary buffer for median filtering
int analogBufferIndex = 0, copyIndex = 0;
float averageVoltage = 0, tdsValue = 0, temperature = 25.0; // Set default temperature

/*Enter the Minimum and Maximum Values which getting from Calibration Code*/
int R_Min = 111;  /*Red minimum value*/
int R_Max = 359; /*Red maximum value*/
int G_Min = 108;  /*Green minimum value white*/
int G_Max = 351; /*Green maximum value black*/
int B_Min = 104;  /*Blue minimum value*/
int B_Max = 310; /*Blue maximum value*/
int color_health = 0;

/*Define int variables*/
int Red = 0;
int Green = 0;
int Blue = 0;

int redValue;
int greenValue;
int blueValue;
int pulseWidth;
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
void setup() {
  pinMode(S0, OUTPUT);
  pinMode(S1, OUTPUT);
  pinMode(S2, OUTPUT);        /*Define S2 Pin as a OUTPUT*/
  pinMode(S3, OUTPUT);
  pinMode(TdsSensorPin, INPUT);    // Set TDS pin as input
  pinMode(LED_PIN, OUTPUT);
  pinMode(sensorOut, INPUT);  /*Define Sensor Output Pin as a INPUT*/
  digitalWrite(S0, HIGH);
  digitalWrite(S1, LOW); //20%
  WiFi.mode(WIFI_STA);
  ThingSpeak.begin(client);  // Initialize ThingSpeak
  Serial.begin(115200);       /*Set the baudrate to 115200*/
  //delay(1000);                /*Wait for 1000mS*/
}
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
void loop() {
  // Connect or reconnect to WiFi
if(WiFi.status() != WL_CONNECTED){
  Serial.print("Attempting to connect");
  while(WiFi.status() != WL_CONNECTED){
    WiFi.begin(ssid, password); 
    delay(5000);     
  } 
  Serial.println