What is Turbidity Analyzer?
Turbidity analyzer is used when there is a need to add display function, control, alarm and automatic sensor cleaning to a transmitter with 4-20 mA output.
Turbidity analyzer is a system that used for monitoring and controls the single or differential measuring and consists of two important parts:
- The controller
- The 0-20 mA or 4-20 mA transmitter connected to a suitable sensor
In some application it is necessary to measure before and after the process in order to obtain the difference of the two measuring. The analyzer allows a differential measuring, by using two transmitters featuring the same measuring scale.
Turbidity Analyzer Working Principle
The low turbidity measurement uses nephelometric method. A light beam of a given wavelength is sent into the sample through a transparent lens. The portion of light diffused at an angle of 90o by the suspended particles in the sample returns to the probe through a second optical lens. Then it is detected by the internal circuit and converted into an electrical signal proportional to the sample turbidity. The infrared light source makes the measurement independent from the sample color.
The high turbidity or suspended solids measurement uses back scattering method. A light pulse is sent into the sample through a transparent lens. The light reflected by the particles suspended in the sample returns almost perpendicularly into the probe through a second lens. Then it is converted into an electrical signal which depends on the concentration and the shape of the particles. The infrared light source makes the measurement independent from the sample color.