Section 4 — Measurement Types and their Uses
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Coast-down/Run-up
Coast-down and run-up measuring involves taking a series of recordings
with a short delay between them. You can use this technique to study
the resonance behavior of a machine as its speed gradually increases
during power-up, or decreases during coast-down.
Tips for Coast-down/Run-up recordings
We recommend using a tachometer to obtain the RPM reading for each
measurement as this will aid interpretation.
You can set the recording interval as a time interval between recordings
or a change in machine RPM. We suggest setting it to a change in
machine RPM, 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.
Several recordings are taken during a coast-down or run-up. If you
intend to repeat the process several times on a machine, we
recommend you save each set of recordings to a separate location so
you can easily distinguish between these.