Allow selection of output timestamp for values written by the outputs at close feature in Event Frames
It would be nice to have the option to select either starttime or endtime of the eventframe as the timestamp for the value that will be written a PI tag using the Outputs at close feature in Event Frames. Currently, it will only write the value with a timestamp of the endtime of the event frame.
I have an event frame and I would like to see the average of an attribute value for that duration of that time frame on PI Vision. The expectation is to see a horizontal line indicating the average value throughout the duration of the event frame.
As of now, the average value is written to the underlying PI Point with the timestamp at the end time of the event frame using the Outputs at close feature in Event Frames.
This leads to a sloping trend when you try to visualize the resultant average values. i.e. the trend links the previous average value (calculated from the end of the previous event frame) to the latest event frame output average value.
With the requested option available and combined with the step parameter in the PI tag, we will be able to visualize a straight horizontal line for the average value of the tag for the duration of the event frame for that particular duration.
Christoph Rose commented
We have a lot of summary calculations for event frames (things like minimum and maximum values of certain attributes). For visualisation in PI Vision it would be very helpful to be able to set the output timestamp to the start time of the event frame, as this way viewing the data during the event frame (using an event frame table and applying the time range) would also show the correct value for that summary value.
Currently the summary value is not visible, as it is written at the very end of the event frame.
Roger Palmen commented
Being able to write to the starttime of the EventFrame is at least one of the key things required for proper trending
Great idea !
In some sites we count daily production based on batches started on the day, so the final values of a batch should be stored with the timestamp of the start time. I think the best solution would be the possibility of using a variable as output time stamp like we have in the advanced options for an Expression Analysis (using the EventFrame function it could also be the Event Frame start time).
Rafael Batista commented
Currently, Event Frame outputs are saved with the EF End Time timestamp. It would be interesting to use the StartTime instead.
It would be usefull to have access also to the Duration of the event befor it closes. If the Duration could be output in 'live' envent, we would be able to get child event generation after a fix amount of time after the parent event starttime.