Rockwell Automation Logix5000 Controllers Controller Information and Status Programming Manual - Manual (Page 26)

Chapter 3 Controller logging
• Change to constant tag configuration reset
• Mode change
• Major fault, major fault cleared
• Program properties modified
• Task properties modified
• Controller timeslice modified
• Removable media inserted or removed
• Safety signature created or deleted
• Safety locked or unlocked
• Custom entry: User-defined logic to create a log entry, with user-defined
entry description and extended information
• Safety signature delete inhibited in Run mode
• Safety signature delete allowed in Run mode
• The Changes To Detect value has changed
• Log Collected Data Cleared
• Program Connection Modified
Controller log buffer
The controller keeps up to 100 log entries buffered in its internal memory. You
can configure the controller to write the buffered entries to the removable media
when its internal buffer is 80% full. Additionally, you can command the controller
to write the buffered entries to the removable media with a message instruction.
This procedure is detailed below. Once a log entry is written to the removable
media, it is removed from the buffer.
If the removable media is not present, is full, or if the controller is not configured
to automatically write buffered entries to the removable media, and the internal
buffer becomes full, entries continue to be saved in the buffer in a circular fashion.
As new entries are stored, the oldest entries are discarded.
Controller log files and the removable media
When written to the removable media, controller logs are stored in plain text files
in the Tab Separated Value (TSV) format. Each time the controller writes entries
to the CompactFlash card, the entries are appended to the text file until the file
reaches 1 MB in size. At this point, the controller creates a new text file.
26 Rockwell Automation Publication 1756-PM015F-EN-P – October 2014