This tab is used to configure “evidence” in the form of tag data that may be assigned to an alarm event. An aggregated value of the evidence tag over the duration of the event can be attached to the event. For example, the average value of a machine speed tag may be used as evidence for a slowdown event. Once the Evidence Class has been configured on this screen, it must be associated with one or more reasons in the reason tree before it can be assigned to an event.
•Evidence Class: Name of the set of values from which Evidence can be selected on the Alarm Reasons tab.
•Allow Multiple: Allows multiple items from the Evidence Class to be selected when assigning a cause.
•UTag: The tag for which values will be captured for the Event.
•UTag Data Mode: The aggregate that will be displayed by the evidence tag.
o Time Average: The time-average of the data during the event.
o Start: Value at the start of the event.
o End: Value at the end of the event.
o Count: The number of data points during the event.
o Delta: The change in the value from the first event to the last event.
o Maximum: The maximum value during the event.
o Minimum: The minimum value during the event.
o Time Average 2: Same as Time Average but does not carry last known good quality point forward across bad quality interval.
o Range: The difference between the raw maximum and the raw minimum values in the interval.
o Reg Dev: Retrieves the standard deviation of the regression line over the interval.
o Reg Slope: Retrieve the slope of the regression line over the interval.
o Total: The time average multiplied by the number of seconds in the interval.
o Sum: The sum of all the data points during the event.
•Variable Name: This is used for production reporting. It is a way to give different variables a common name for reporting. For instance, if several rows are given the same name, the event data can be sorted and displayed with “Variable Name” as grouping criteria.
•Evidence Value: A picklist for the Evidence Class (row). Each Evidence value will be an option for the picklist. Used to separate evidence classes into different types.