PRÜFTECHNIK VIBXPERT II - Time-Synchronous Average (Postprocessing)

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VIBXPERT II 05.2012
Time-synchronous average (Postprocessing)
If a trigger signal is recorded in addition to the time waveform, fur-
ther information can be obtained.
For example, the time waveform can be determined synchronously
with every rotation of the shaft. In this way, events in the signal that
are synchronous with the RPM are emphasized and stochastic results
are suppressed.
If the measurement locations are on a gearbox, the time waveform
can be determined for one rotation using the transmission ratio of the
gearbox.
• PresstheMENUkey.
• Select‘Postprocessing’andclickon‘Times-ynchronousaverage’:
- If you measured the RPM simultaneously with a trigger sensor,
activate the 'Use trigger mark' option and enter the number of
'Revolutions'pertriggerpulse.Usingthe‘Startattrigger’option,
you can synchronize the time signal using the trigger pulse.
- If there is no trigger signal, you can simulate it by using a manually
entered RPM value ('Custom revolution'). In this case, the trigger
optionsdescribedabovearedeactivated.TheRPMvalue(inHz)
corresponds to a block length in the time signal described by the
relationship f= 1/t.
- In the ‘Revolutions’ field, you can compensate for any differences
in RPM between the trigger measurement location and the signal
measurement location (e.g. the translation ratio in the gearbox).
Close Postprocessing
• PresstheMENUbuttonintheresultscreen.
• Select‘Postprocessing’andclickon'Data'.
Results
Time-synchronous average:
Configuration