NFRA LEVEL SWITCH instruments are suitable for the detection of liquid level in small vessels where space is limited. Level detection is unaffected by electrical and physical parameters of the media such as conductivity, dielectric constant, density, viscosity, air bubbles, color and refractive index. It is very compact and fits in constrained spaces. It is unaffected by vapour and can be easily removed, cleaned and reinstalled. It has no moving parts and can be used for the detection of level.

An infrared emitter sends pulsed light into the prism. When the prism is not covered by the media, the light undergoes a total internal reflection and the returning beam is detected by the Photo Detector. When the Prism gets covered by the media the light is dispersed and only a weak beam returns to the Photo Detector. The change in the received intensity is processed by the electronics to signal.