Abstract:
An apparatus and method for measuring the level of a wide range of varied surfaces or materials housed within vessels, and for detecting contact with a solid surface within the vessel is disclosed. A high precision radio frequency admittance measuring system, using capacitance to measure levels of process materials, coupled with detection element to sense contact of the detection element with a solid surface, such as a floating roof. An active element and ground element in coaxial relationship provides means for measuring the level of process materials including water, oil, kerosene, jet fuel, gasoline. Along with detecting the level of a solid surface within the vessel such as a floating roof. One preferred application of the inventive apparatus is to provide vessel or tank overfill protection. The apparatus detection element is capable of sensing level and non-level solid surfaces.