Spectrum
Last updated
Last updated
The Spectrum view displays data related to the FFT in a graphical representation. At the machine level, all the FFTs of all the devices attached to the machine are available, while at the device level, only the FFTs of the selected device can be seen.
The Spectrum view contains the following sections:
Asset tree
FFTs List
Acceleration spectrum
Velocity spectrum
Clicking the items in FFTs list will select the spectrums to be displayed in the graphs for acceleration and velocity. Clicking the checkbox next to Device will select or unselect all available FFTs, the date can be sorted descending or ascending, and clicking in the trash icon will delete the selected FFTs.
Please note that deleting an FFT is irreversible.
A legend with the selected FFTs is available on top of the graph for both the acceleration and the velocity spectrum. Clicking on any of the items will toggle the activation in the graph.
Hovering on an item in the graph's legend will make the graph focus on the hovered measurement. In the example shown below, the mouse is hovering over the orange item.
Additionally, the FFTs list will also focus on the respective item in the table providing clear insight into which FFT corresponds to which FFT in the list.
The specific value of a point in the graph can be seen by hovering on the graph. By doing so the frequency and magnitude of that point in the graph will display.
The graph functions are options available in the top right corner of the acceleration and velocity spectrum graph. These options allow the user to change what is displayed on the screen to assist in data analysis. The options available are as follows:
Fullscreen: expands the graph view to fullscreen.
Export: download the graph's data in CSV format.
Toggle sideband cursors: show or hide sideband cursors if added to the FFT.
Toggle harmonic cursors: display or not the harmonic cursors in the graph.
Toggle RPM: activate or deactivate the RPM indicator.
Toggle bearing faults: if bearing faults are defined, clicking this icon will toggle the bearing fault guides.
Toggle thresholds: show or hide threshold guide lines.
Toggle CPM: Rescale the horizontal axis to CPM or back to Hz.
Units changer: change the units used in the graph among the available options. For acceleration: G, m/s², ft/s²; and for velocity: mm/s and inch/s.
An example of some of the available options previously mentioned turned on is presented next,
Cursors can be added to a spectrum graph in two ways. The first option is to hover a point in the graph and click the desired starting point.
After that, the user can select to set harmonic or sideband cursors. An example of both cursors set with this method is shown below.
An alternative option is, with the toggle of the cursor of interest on, to click the vertical ellipsis in the top left corner of the graph. This will allow the user to set or edit the values and thresholds of the cursors toggled on.
With the cursors on the user can click on them to remove them or drag them to a different position.
Point annotations can be accessed and added by clicking on a point in the graph. This will make a pop-up window appear where the user can read previous annotations or add a new one.
The user must add a title and description, additionally, the user can include the harmonic cursors if these are on the graph by marking the checkbox at the bottom of the pop-up window.
Point annotations will show at the point of the graph where they were saved. An example of this is shown below.
General annotations can be accessed using the vertical ellipsis on the FFTs list. Clicking on it will make a drop-down menu appear with the option Annotations.
Clicking on the aforementioned option will display a pop-up window where the user can add general, and read previous general and point annotations.
