Cascade lets you collect a specified number of spectra in succession. Collected spectra display in a waterfall graphic with a three-dimensional effect.
Collect a Cascade to determine resonant frequencies during coast downs or start ups. You can also observe transient events caused by changes in loads or processes during normal operation.
- Create a job.
- From the Analyze main menu, press .
- Use the up and down arrow keys to select Cascade.
The Analyze Setup screen appears.
Set the following options as necessary.
Option Description F2 Set Spectra Params Set the Fmax, Fmin, and lines of resolution. See Fmax and Fmin and Lines of resolution. F3 Set Cascade Params Set the number of spectra to collect, force an RPM measurement, and select the sample type to set how the analyzer collects new data. The sample type is not the same as a trigger and takes precedence over a trigger. Select Continuous to collect data immediately, Delta Time to collect after a specified time interval, or Delta RPM to collect after a specified change in RPM.
For Delta Time samples, select the minimum time delay (in seconds) between the start of each collected spectrum.The default is 20 spectra, Force RPM is disabled, and Continuous mode is selected.
F4 Set Window Set the type of window to use. See Windows. F5 Set AWeight Apply a shape curve to the acquired frequency spectrum that approximates the frequency sensitivity of the human ear. Aweighting is used with microphone signals when you want to see perceived “loudness.” A high sensitivity, low frequency sensor is recommended. Use a general purpose accelerometer, such as part number A0760GP, for measurements as low as 40 RPM. Contact customer service for recommendations to measure lower frequencies. F7 Tach Setup Set up the tachometer parameters. See Set up a tachometer in Analyze. F8 PeakVue Demod Enable or disable PeakVue or Demodulation. See PeakVue and demodulation. F9 Set Trigger Set the type of trigger to collect data. The Level Trigger and RPM Trigger only start collection of the very first spectrum in the series. All other spectra are collected without a trigger. These two modes do not permit pre-triggering. When using the Tach Trigger, a Set Tach Start option is available. See Triggers. By default, the trigger is disabled. F12 Input Setup Set up the input channels, the sensor type, and the units for the acquisition type.
Enter to collect the data.
One or more plots display the data.
- Press F9 Store Data to save the data, or press F8 Start to redo the measurement.