The Triton TR8 is a nephelometric turbidity sensor designed for use in water and wastewater. Turbidity, the cloudiness or haziness of a water sample, is caused by particles suspended in the water, typically clay and silt. Since bacteria and viruses can be attached to these particles, turbidity has become a critical indicator of the overall water quality.

The Triton TR8 uses an optical method for determining the turbidity suspended solids, a light beam is directed into the sample where it is scattered by suspended particles in the water. The amount of scattering depends on the amount of material in the water, the wavelength of light used and the size and composition of the suspended particles.

The Triton TR8 uses a long lived near infrared LED light source (880 nm) and the 90° scattered light method in accordance with ISO 7027 / EN 27027 to assure accurate turbidity values under standardized and comparable conditions. The 90° scattered light detection method is the most common sensor design for turbidity. This sensor has the advantage of a high sensitivity at low levels of turbidity, a simple optical configuration and a balanced sensitivity to all particle sizes. Three detectors monitor the light beam at an angle of 90°. The first detector, inside the sensor, (see Figure 1) is the reference detector that compensates for changes in the LED light source caused by aging or other variations. The second detector measures a short path length which is best for high concentration measurements. The third detector measures the longer path length which is best for lower concentrations. The turbidity signal is constantly adjusted versus the reference detector, digital filter functions suppress interfering signals and self monitoring diagnostics assure a highly reliable measurement.