Modern appliances use turbidity sensors to determine how "dirty" the laundry water is. If the water remains relatively clear during the wash cycle, the controller might skip the rinse cycle to save water. The YL-105 (or its industrial equivalent) detects the point where suspended soils have been flushed away.
The relationship between the sensor output and water quality is non-linear but predictable.
Below is a basic code structure for interpreting the data:
const int sensorPin = A0;
void setup()
Serial.begin(9600);
void loop()
int rawValue = analogRead(sensorPin);
// Convert raw ADC (0-1023) to voltage (0-5V)
float voltage = rawValue * (5.0 / 1024.0);
// Invert logic for intuitive reading (Higher value = Dirtier water)
// This requires calibration against known samples.
Serial.print("Voltage: ");
Serial.print(voltage);
Serial.println("V");
delay(500);
Since an official unified datasheet for "YL105" is rare (the number often refers to a module, not a single IC), below are the typical electrical and magnetic specifications derived from common Hall sensors used in YL105 modules.