Fault Detection with Vibration Transducers

Mechanical faults, usages, slackness's, cause different noises and vibrations with different amplitude and frequency against the normal sound and movement of the equipment.The vibration transducers, accelerometers and microphone are used for noise and/or sound and vibration detection with fault detection purpose. Vibration transducers and accelerometers have three functioning domain, if the input frequency is les then the resonant frequency of the sensor it is working as an accelerometer, if the input frequency is higher then the resonant frequency of the sensor it is working as vibrometer. Detecting and analyzing the signal of the transducer, amplitude and spectral analyzing, we can detect usages, slackness and forces which act and produce the fault. Analyzing the output signal of the sensor and compare with a base signal or with nominal values mechanical faults can be detect in functioning time without stopping and to take to pieces the equipment. It is an undestroyed method to find out the functioning problems.In this paper are presented simple transfer functions for two cases, if the mechanical system is vibrating and if through the base is transmitted a vibration to the system. The system behavior is analyzed in Matlab surround the natural frequency of the system. The amplitude and phase modification can be used for signal analysis and fault detection.