Diseño y construcción de un sensor capacitivo de nivel
Abstract
This article shows the development of a level sensor for use in industry to measure the amount of liquid in tanks. It begins by explaining how confront the problems of construction, interference and isolation of sensor. Is performed the sensor design in CAD and construction from the plans generated by the software. With the built sensor is evaluated the performance with different types of liquid and makes the circuit design to eliminate noise and linearize the behavior. With the previous design of the circuit is made the assembly between the sensor and the PC. It develops a graphical environment on the PC via USB for the user can to monitor the behavior of the sensor, in the programming of graphical environment is designed a discrete low-pass filter to improve the sensor response to disturbances. According to the dates obtained is verified the mathematical model and estimate the capacitance values of different fluids working as dielectric. The behavior of the sensor is linear and it works for tanks with different diameters, a height maximum of 25 cm and to different liquids.
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References
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