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Below each cavity are two status bars. The left status bar indicates whether the SSA is On or Off, while the right status bar indicates whether the RF is On or Off.
Figure 2: Example of a cavity with its SSA on and RF on
Understanding Cavity Faults
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Although cavities may have multiple faults at one time, the display can only show one fault at a time and it is designed to show the highest priority fault (aka the most severe/concerning fault) first. To see what other faults may be affecting a specific cavity, we can open a a cavity 's fault panel. To do this, we first click on a CM number directly from the Cavity Display. From there, we'll get a panel with a list of cavities. Click on the cavity number to open its fault panel.
As mentioned above, the cavity fault panel lists fault panel for the cavity by clicking directly on the cavity widget. The resulting fault panel will display all the possible faults in order of decreasing priority. To see the PV associated with each fault, we can middle click the fault status box (which will display "OK", "FAULTED", or "INVALID").
Figure 3: Cavity fault display panel showing all faults for a given cavity
Next to each fault status is a button that will act as a direct link to the relevant EDM panel associated with a given fault. This feature was implemented to make troubleshooting specific faults easier. Most of the display links are functional, but additional effort is still being made to integrate the panels that take non standard handling (i.e. cryo, pydm, and 3.9GHz screens).
GUI Backend
The Cavity Display GUI has a watcher status in the upper left hand corner to communicate whether the backend code is running. For a little background on how our watcher works: the backend code has an incrementing PV (PHYS:SYS0:1:SC_CAV_FAULT_HEARTBEAT) that will continuously update as long as the backend code is running. If this incrementing PV stops incrementing, then the watcher PV (ALRM:SYS0:SC_CAV_FAULT:ALHBERR) watching it will change its status from "RUNNING" to "NOT RUNNING."
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