Rockwell Automation 2706-MB1 MESSAGEVIEW 421 SOFTWARE MANUAL - Manual (Page 67)

4–19 Planning an Application
Publication 2706-817
The MessageView terminal features a Historical Event (HE) Stack.
The HE Stack file supports up to 4000 messages, each 21
alphanumeric characters long. Messages with the HE Stack attribute
enabled are recorded in the Historical Event Stack each time they are
triggered.
The Historical Event Stack file includes for each message:
•
Message number.
•
Message text, which includes:
– data display variables at the time of triggering
– placeholders for data entry variables
– placeholders for graphic symbols.
•
Message topic.
•
Time and date when the message was triggered.
•
Time and date when the message was acknowledged, if the Ack
Time attribute was enabled. See Page 7–39.
Historical Event Stack messages are stored in the terminal’s memory
in chronological order.
The terminal can alert the operator when the Historical Event Stack
file is 85%, 95% and 100% full, so that overflows can be avoided. If
the Stack file is full, new messages overwrite messages in the file,
starting with the oldest.
Viewing the Historical Event Stack
The Historical Event Stack may be viewed using either:
•
the terminal’s Front Panel Editor
•
the personal computer via the HE Stack Upload command.
When using the Front Panel Editor, the terminal operator may view
the Historical Event Stack in either of two formats:
•
frequency of occurrence
•
chronological order.
The HE Stack Upload command, on the Application menu, uploads
the HE Stack file to a computer file in CSV (Comma Separated
Variable) format. This format allows the user to import the file into a
spreadsheet or database software package for analysis. See Page
11–13.
Historical Event Stack