In the case, if the software “Shaker calibration” is not available, it is still possible to conduct all necessary measurements using ZETLAB software package. The acceleration and/or displacement harmonics ratio are evaluated in the nominal frequency range at the upper limit of acceleration and (or) displacement ranges by means of the program “Non-linear distortion analysis”.
The program “Multichannel oscilloscope” is used for control of acceleration and displacement graph.
Using the program “Signal generator” it is possible to calculate the displacement harmonics ratios (at generator frequency level below 50 Hz) and acceleration harmonics ratios (at generator frequency level over 50 Hz).
Figure 1. “Vibration meter” program
In order to calculate displacement harmonics ratio, double-integer the acceleration signal in the program “Vibration meter”. Start the program “Vibration meter”, set the band filter range “3.0 – 10 000.0 Hz”, measurement method – “Amplitude”, averaging time – “1 second” (figure 1).
Figure 2. “Non-linear distortion analysis” program
Figure 3. “Narrowband spectrum” program
“Frequency meter” program is used for the purpose of the reference vibration transducer frequency control. “Multichannel oscilloscope” program is used for the reference vibration transducer frequency curve control. The program “Narrowband spectral analysis” (figure 3) allows to observe the carrier frequency of the signal and corresponding harmonics. The program “Non-linear distortion analysis” (figure 2) is used for calculation of ratios for each harmonic, estimation of the true signal shape and distortions.
The program “Non-linear distortions analysis” is used for control of a number of signal’s parameters. For the purposes of vibration exciter (shaker) calibration, set the harmonic distortion ratio “THD(f)”.