Rockwell Automation 825-P Modular Protection System for Motors User Manual - Manual (Page 109)

Rockwell Automation Publication 825-UM004D-EN-P - November 2012 109
Chapter
8
Analyzing Events
Overview The 825-P relay provides several facilities to analyze the cause of relay trip
operations. Use these tools to help diagnose the cause of the relay trip operation
and more quickly restore the protected motor to service.
Each tool listed below provides increasing detail regarding the causes of a relay
operation.
• Event Summary Reports
• Serialized Events Recording
Event Summary Reports Each time the 825-P trips and in response to other selected conditions, it captures
motor current and voltage (if included). This collection of data is called an event
summary report. This section explains what causes the relay to save an event
summary report, and what the event summary data means.
The relay stores the five most recent event summary reports in nonvolatile
memory. These reports are numbered 1 through 5. When the relay stores a new
report, it discards the oldest report if five reports are already in memory. Use the
event summary data to help discern the cause of relay trip operations.
View the present collection of event summary reports using the front panel
Events menu selection or the serial port. Each event summary report includes the
following information:
• Type of event, from the list of event type strings in Figure 24
• Event number, date, and time
• Magnitudes of the line, core balance, and residual currents
• Magnitudes of the line-to-neutral (wye) or phase-to-phase voltages (delta),
if included
Report Triggering
The 825-P triggers an event summary report when the relay trips by protection
elements.