← All projects

Level Measurement with a Water Level Sensor

A starter project that reads the water level sensor's analog output and writes the level as Empty, Low, Medium or High to the Serial Monitor once a second. As the sensor's parallel tracks go under water, the resistance drops and the reading rises. The thresholds (100, 400, 450) depend on the water's conductivity and the sensor; watching the raw values first and setting your own thresholds gives better results. Only dip the lower part with the tracks in water; keep the electronics and pins at the top dry. To reduce corrosion, do not leave the sensor powered all the time. No extra library needed.

What you need

• 1 × Arduino Uno R3
• 1 × Water Level Sensor
• 3 × Jumper Wire - Male/Female

Wiring steps

1. 1

   Power the sensor

   

   Plug a red jumper wire into the 5V pin on the Arduino's POWER header. Connect its other end to the sensor's pin marked +.

2. 2

   Ground (GND) connection

   

   Plug a black jumper wire into the GND pin on the Arduino's POWER header. Connect its other end to the sensor's pin marked −.

3. 3

   Connect the signal (S) line

   

   Plug a blue jumper wire into pin A0 on the Arduino's ANALOG IN header. Connect its other end to the sensor's S (signal) pin. The code reads the water level on this pin as a value from 0 to 1023 (sensorPin = A0).

Arduino sketch

const int sensorPin = A0; 
int value = 0; 

void setup() {  
    // analogRead için pinMode tanımlamaya gerek yoktur, donanımsal olarak ayarlanır.
    Serial.begin(9600); 
}  

void loop() {  
    value = analogRead(sensorPin);  
    
    if (value <= 100) {  
        Serial.println("Water Level: Empty");  
    }  
    else if (value <= 400) {  
        Serial.println("Water Level: Low");  
    }  
    else if (value <= 450) {  
        Serial.println("Water Level: Medium");  
    }  
    else {  
        // Değer 450'den büyükse otomatik olarak buraya düşer
        Serial.println("Water Level: High");  
    } 
    
    delay(1000);  
}

What the Serial Monitor shows

Water Level: Empty
Water Level: Empty
Water Level: Low
Water Level: Low
Water Level: Medium
Water Level: High
Water Level: High