Coast Down Peak and Phase confirms resonance during a coast down, but requires tachometer input from the shaft turning speed. You want the operational vibration to excite the resonant frequencies in the system as the equipment coasts to a stop. The measurement records the amplitude and phase of the 1xRPM frequency. The results show a peak at any resonant frequency. At a resonance, the phase goes through a 180-degree phase shift.
Note: By default, the peak/phase coast down monitors the first harmonic of the turning speed. To perform the test on a different harmonic, use a cursor to mark a frequency before running Coast Down Peak and Phase.
- Create a job or open Analyze from a route measurement point.
- From the Analyze main menu, press .
- Press Start or Enter to collect the data.
- Shut down the equipment.
- Press F3 Stop or F9 Stop when the equipment stops.
Press Enter to view the data.
One or more plots display after the data is collected.
- Press F9 Store Data to save the data to a route or a job, or press F8 Start to redo the measurement.