Rockwell Automation T80020 Application Note Diagnostic Procedures - Manual (Page 4)

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AN-T80020 Diagnostics Procedure
Issue 12 Feb 11 AN-T80020 4
First-line Diagnostics
Every day, check the processor’s System Healthy LED. If this is green, there are no system faults.
There may still be communications problems and field wiring problems.
If the System Healthy LED is flashing red, there is a system fault. Look at the other diagnostic LEDs in
the table on the next few pages.
Each module has ‘Healthy’ LEDs, one for each slice of the module’s circuitry. The Communications
Interfaces (8151 or 8151B) are not triplicated and so only have one LED.
Do not press the main processor reset pushbutton or remove and reinsert a module unless specifically
advised to do so in the procedures below. Pressing the reset pushbutton may clear important
diagnostic information. Removing and reinserting a module may cause shutdowns and will also clear
some fault information.
Keep a logbook for recording error codes from I/O modules. Record the error code, module position
(chassis and slot or reference number), date and time. If the advice in this document for that error code
is to act only if it is persistent (returns later after pressing Reset), use the logbook to look for earlier
records of the same fault.
LED colour Reason Procedure
Processor
'Healthy'
LEDs are
red Processor
module fault. Collect the processor’s current system log. The procedure is
described in a section below.
Obtain a replacement processor module of the same or later build.
Swap to the replacement module.
If the fault appeared after the processor was restarted, it is likely that
a memory corruption has occurred because the education process
had not completed. Refer to TN20014.
Processor
'Educated'
LED is not
steady
green
No application The Standby Processor takes a few minutes to synchronise with the
Active Processor. It should not be removed during this time. If it has,
memory corruption may occur. Refer to TN20014.
The Active Processor may have no application loaded.
The Standby Processor may not have started or completed its
education from the Active processor.
Active
Processor
'Run' light
is not
flashing
green Application not
running The 'Run' light is always steady green on the Standby processor.
The Active processor should show a flashing green 'Run' LED.
The 'Run' LED is off when the application in the Active processor is
stopped.
If the ‘Run’ LED has stopped when it should not have, then the
system has detected a fault of some kind. This should be reported to
ICS Triplex Technology. Refer to the section below describing Action
on Processor Shutdown. This describes how to collect diagnostic
information which may be lost during attempts to restart.
Processor
'Inhibit'
LED is
flashing
green
The processor
cannot be hot
swapped The 'Inhibit' LED flashes green when any input or output is locked, as
a warning. This LED also flashes green when the current Standby
Processor has an incompatible system configuration. A changeover
from the Active to the Standby processor will not work if the Inhibit
LED is flashing. To enable a swap in this second case, remove and
reinsert the Standby processor to load the system configuration.