OPTISWITCH is a level sensor with tuning fork for level detection. It is designed for industrial use in all areas of process technology and is preferably used for bulk solids. The vibrating element (tuning fork) is energized piezoelectrically and vibrates at its mechanical resonance frequency. The piezos are separated mechanically and are hence not subject to temperature shock limitations.When the vibrating element is immersed in the product, the vibrating frequency changes. This change is detected by the integrated oscillator and converted into a switching command.