Artesis AMT Toolkit, Руководство пользователя

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Equipment Faults, Diagnosis and Reporting
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Current Unbalance: Current unbalance of an electric motor system is defined as the
percentage of the maximum deviation of phase currents from the average current. Current
unbalance causes motors to overheat and lose torque. Developing short circuit faults due to
the degradation of isolation materials may also cause increasing or decreasing current
unbalance over time. Electric motors should not be operated with high current unbalance.
Software alerts the user when the current unbalance exceeds 3%.
4.3. Advance Use; Power Spectral Density
Although AMT Toolkit excels at providing the user with actionable information in a concise,
practical form some advanced users choose to make use of the more complex displays that
it can also provide. Power Spectral Density displays indicate the way the system has used
information about the frequency content of the measured signals.
The spectral analysis using psd plots are similar to spectral analysis used in vibration
analysis including fault frequencies except that the fault peaks appear as sidebands around
line frequency at a distance equal to fault frequencies.