Use event comparisons
- Last UpdatedFeb 26, 2025
- 2 minute read
AVEVA PI Vision lets you compare events such as process downtime, process excursions, operator shifts, or batches. With the event comparison feature, you can analyze process data across multiple events on a single overlay trend. The feature is designed to help you identify similarities and differences between events, assess sub-events, and determine root causes.
By default, the event-comparison page displays up to 11 events, including the event you selected in the Events pane as well as ten earlier events of the same type. Each event is color-coded and has a legend marker next to its name to help you locate the event on the overlay trend and the Gantt chart. Drag and drop additional attributes. Select whether to display each attribute on a separate trend or all attributes on a combined trend.
The following figure shows the event comparison page.
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Callout |
Description |
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1 |
Events pane listing all the events you are comparing. |
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2 |
Overlay Trend display showing overlay trends for each attribute of the event and the asset you want to analyze. Each overlay trend shows multiple events for a single event attribute. For example, an overlay trend for an attribute called "Downtime" will show a graph with 11 traces with each trace representing a different downtime event. |
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3 |
Zero Line marking the start time of the event. |
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4 |
Attributes pane listing all the attributes associated with the event you want to analyze. |
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Root Cause showing the time period leading up to the event that is considered a "child" event. |
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6 |
Gantt Chart pane representing each event in the Events pane with a color-coded Gantt bar. The position and length of the Gantt bar reflects the start time, duration, and end time of the event. The Gantt bar shows if there are "child" or other descendant events associated with the event, such as root causes. |
Videos
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Related Links
- Compare multiple events
- Pin reference events
- Pan an event comparison
- Zoom in on an event comparison
- Maximize an event comparison
- Add a new overlay trend to the display
- View child events in Gantt chart
- Align and zoom in on child events
- Perform root cause analysis
- Configure an event comparison
- Save an event comparison display