The RF Capacitance Level Switch is designed to provide accurate and reliable point level (high and low level) information for solids (powders and lumps), liquids, and slurry stored in vessels and tanks. The electronics consist of an oscillator, a detector, and an output relay which is controlled by the detector. The probe contains an active section and a shield section insulated from each other and from the vessel's ground. Most conventional sensors give a false indication when coated due to build up. EIP Level Sensors are designed to ignore any such build-up or coating. The standard RF capacitance probes detect the presence or absence of material in contact with the probe by sensing minute changes (as low as 0.5 pF) in capacitance caused by the difference in the dielectric constant of the material versus the air. They feature interference-free operation, simple calibration, and fail-safe functionality and perform accurately even in dusty, sticky, or clinging materials. Class II hazardous location ratings and a wide assortment of probes and extensions make these point-level capacitance probes appropriate for a variety of solid, liquid, and slurry materials.