BERAN

Proven Condition Monitoring Solutions

Glossary

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    • Lines on an FFT

      An FFT resolves the input accelerometer signal into a number of discrete lines or bins. The larger the number of lines the greater is the detail and clarity of information that can be extracted. For example a typical 0 to 500Hz FFT analysis, at a resolution of 200 will sample the signal and produce one lines for all frequencies between 0 Hz and 2.5 Hz, and another for frequencies between 2.5 Hz and 5.0 Hz etc. (500 / 200 = 2.5). This may be satisfactory for some circumstances. However if it is known that in the aircraft there are gears, shafts or other components which are generating frequencies closer than 2.5 Hz then it may be impossible to identify them correctly. This will necessitate using a higher 400, 800 or even 6,400 'line' resolution.