Coast-Down/Run Up - Commtest Instruments vbBalancer Instrument Reference Manual

Coast-down/Run up

Note: This feature is not available on the vbBalancer instrument
model.
Coast-down and run-up measuring involves taking a series of
recordings with a short delay between them. This technique can be
used to study the resonance behavior of a machine as its speed
gradually increases
coast-down.
From the Main Menu press
•
press
Use the left-hand arrow keys to select a parameter set or
•
press
required.
Press
•
measurements to, then press
After the first spectrum has been recorded switch off the
machine, or begin ramping its speed up or down.
Once the machine has stopped rotating, or its speed has
•
been fully adjusted, press
to the Coast-down/Run-up Menu.
The measurement location will contain a large number of
measurements.
Recommendations
We recommend using a tachometer to obtain the RPM reading for
each measurement as this aids interpretation.
You can set the Recording Interval as either a time interval between
recordings, or as a change in machine RPM. We suggest using the
latter, with the RPM Difference set to machine speed / 20. This will
result in approximately 20 recordings being taken during a complete
coast-down or run-up.
during power-up,
Coast Down/Up.
to create a new one and set the parameters as
and select the machine location to save
Section 8: Measurement Types and Their Uses
or decreases
Measure Vibration then
again to begin measuring.
to stop measuring and return
during
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