| 摘要 |
A method and apparatus for measuring at least one parameter including mass flow rate or moisture content of material moved by a conveyor are disclosed herein. The method includes the steps of applying an electric field to the material using a non-intrusive sensor assembly, generating signals related to the dielectric value of the material, and processing the signals to determine the parameter. The apparatus includes a capaciflector sensor assembly located along a surface of the conveyor to generate an electric field applied to the material and a processing circuit to determine the parameter based upon the signals output from the sensor assembly. The sensor assembly includes a first conductor spaced between a stationary member of the conveyor and the material, and a second conductor spaced between the first conductor and the stationary member to act as a shield for reducing parasitic capacitance between the first conductor and a reference plane. The first conductor forms a first electrode of a sensor capacitor and the material forms a second electrode, and the capacitance depends on the parameters of the material. A cover may be located between the sensor assembly and material. The processing circuit performs a frequency analysis over any number of frequencies to determine the mass flow rate, moisture content or type of material, and the conveyor's speed.
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