Rockwell Automation 8000 Series TMR System - Manual (Page 25)

OPERATOR AND MAINTENANCE MANUAL
D o c N u m b e r 5 5 2 8 6 4
I s s u e 0 2 J u n e 2 0 0 4 P a g e 1 5 o f 2 3
5.2 FAULT ANNUNCIATION
The 8000 Series System annunciates faults via the status LEDs fitted to the front
panels of the modules.
Note: A fault indication does not necessarily mean that a module is not operational.
Some faults within a module have no immediate consequence. The failure can be
masked or it can be located in the test circuitry. Nevertheless, the module should
be replaced and returned for repair.
8000 Series module status LEDs and their function in fault indication are detailed in
paragraph 2.
5.3 FAULT FINDING TECHNIQUES
CAUTION
ALWAYS INITIATE A RESET AFTER REPLACING A MODULE. WAIT FOR THE
RESET TASK TO COMPLETE (LED INDICATORS ARE RE-ENABLED) BEFORE
PROCEEDING WITH FAULT FINDING.
Fault finding should always start at the 8000 Series TMR Processor since it
contains the first level of information regarding the operational status of the 8000
Series
System.
After scanning the fault indicators of the system modules to locate the affected
module(s), it is good practice to examine modules and connectors for proper
seating, then initiate a reset to determine if the fault is permanent.
If the fault persists, then module replacement is usually the next action to take.
Transient faults should be examined using the diagnostics facility to determine the
frequency of occurrence and whether any corrective action is warranted.
When removing a module from an I/O sub-system, always be careful to ensure that
neighbouring modules are not disturbed accidentally.