Features

Insensitive to contamination

Modulated infrared minimizes affection from contamination

Insensitive to external light interference

Infrared source uses frequency band with only limited interference, and the circuit response only to the modulated light.

Long service life

The pipe inserted in the tank is made in FEP (fluoric material) that resists chemicals and high temperatures. The material also prevents buildup and contamination.

Principle of Operation

The sensor has two detector rods. One of the detectors has a transmitter and the other a receiver at the end, oriented to face each other. 
The sensor compares the amplitude of the transmitted and received light to know material presence. For example, when the detectors are in water, the transmission amplitude decreases only a little, whereas in sludge, the amplitude of received light is significantly decreased.
The sensor measures the decrease in amplitude and gives an output signal.