Campbell AVW200 series, Instruction Manual

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AVW200-series 2-Channel Vibrating Wire Spectrum Analyzer Modules
Response
Amplitude
Noise Amplitude
Resonant Frequency
Noise Frequency
Beginning Amplitude
Ending Amplitude
FIGURE 5.5-3. Graphs for Evaluating Spectral Analysis of a Sensor
Check the manufacturer’s specification for the sensors frequency
and excitation range before picking the begin/end frequencies
and excitation voltage. NOTE
In Figure 5.5-3, the bottom graph shows the raw time series data recorded from
a vibrating wire sensor after the sensor has been excited with the frequency
swept voltage signal and the top graph shows the spectrum after the AVW200
has applied the FFT. In addition to the wire’s resonant frequency, the spectrum
shows the response amplitude, noise amplitude, and noise frequency. The
AVW200 computes the signal-to-noise ratio diagnostic by dividing the
response amplitude by the noise amplitude. The AVW200 computes the decay
ratio diagnostic from the time-series ending amplitude divided by the
beginning amplitude.
Read more! More comprehensive information about the Spectrum and
Time-Series graphs are provided in Appendix F.
6. The results of the poll may be saved by clicking the Save Last Results tab
at the bottom of the window.
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