TURBIDITY SENSOR

Turbidity sensors are used to measure water turbidity and to estimate water quality. These sensors are used to measure the particles in wash water/dirt water. Turbidity is the process in which the particles of solid matter is suspended in water, rather than dissolved into it. Turbidity testing is an important process in water quality maintenance. The increased level of turbidity raises water temperature because suspended particles absorb heat. The warm water consists of less dissolved oxygen than cold. So when water temperature increases result in a decreased level of dissolved oxygen.

The turbidity sensor works on the optical principle. By using the Transmittance and Scattering rate of a liquid solution, the turbidity is determined.  The sensor uses a phototransistor and a light-emitting diode. The light emitted by the sensor passes through the light-emitting diode source, reflected by sewage, and part of it is transmitted to a phototransistor.  And water turbidity calculated based on the light received. When light passes through some amount of water, the amount of light penetrates depending on the amount of dirty water. When the number of dirt increases, the amount of light penetration through the water decreases. And thereby the turbidity sensor measures the amount of light transmitted to calculate the turbidity of wash water.

The sensor ensures the relative turbidity value and provides both analogue and digital output. The analogue voltage varies with respect to the water turbidity between 0V and 5V. The On-Board Potentiometer was used to pre-set the Threshold value. When the measured Turbidity goes above the threshold level the digital output switches to high, else remain in a low state. The analogue and digital output can be easily interfaced to an Arduino, Raspberry Pi, or other Microcontroller to get turbidity.