Patent ID: 6679123
Filing Date: 2004-01-20
Classification: G01L

Abstract:
A method for self-diagnosis of a piezoelectric strain transducer including at least two electrodes, said method comprising the steps of:under no-load conditions, operating said transducer in an oscillatory mode for generating, at a first electrode, an oscillatory signal defining a frequency; measuring one of said frequency and the amplitude of said oscillatory signal under said no-load conditions; under said no-load conditions, applying a known voltage to a second electrode of said transducer, for generating strain in said transducer; during said step of applying a known voltage, measuring said one of said frequency and the amplitude of said oscillatory signal; determining the difference between said first and second one of said frequency and amplitude; comparing said difference with at least one stored value of said one of said frequency and amplitude, and deeming said transducer to be operable if said difference is near enough to said stored value.