Turbidity Analyzer

Measurement techniques

1. Nephelometric (Scattered Light) Method: This is the most common method, especially for low to moderate turbidity levels.
   • A light source shines a beam into the sample.
   • Particles in the liquid scatter the light at various angles.
   • A photodetector, typically positioned at a 90-degree angle to the incident light, measures the intensity of the scattered light.
   • The amount of scattered light is proportional to the turbidity.
   • This method is particularly suitable for low-turbidity applications like drinking water and pharmaceuticals.
   • Units are typically expressed in Nephelometric Turbidity Units (NTU) or Formazin Nephelometric Units (FNU).
2. Absorption (Transmitted Light) Method: This method measures the amount of light that passes directly through the sample.
   • A light source and photodetector are placed opposite each other, with the liquid sample in between.
   • Suspended particles absorb or attenuate the light passing through.
   • The photodetector measures the reduction in light intensity.
   • This method is generally employed for samples with higher turbidity.
   • Units are commonly expressed in Formazin Turbidity Units (FTU) or Formazin Attenuation Units (FAU). 

Total Suspended Solids (TSS) sensors

• These sensors use backscattered light and often incorporate multiple detectors at different angles (e.g., 90° and 135°) to handle high particle concentrations.
• TSS sensors calculate the concentration of suspended solids and the turbidity of the solution based on the scattered light detected.
• Results are typically displayed in units like milligrams per liter (mg/L) or parts per million (ppm).