Clear Crash Log in PLC-5

Hello All,

Does anyone know how to clear the PLC-5 Crash log without disconnecting the battery and powering it down?

Is it possible with RSlogix-5?

Thanks

What is a "PLC-5 Crash log"? Do you mean the Fault bits? If so, then here is how to clear them.

Clear Minor Fault
A minor fault indicates a status change (for informational purposes only) or that a problem occurred, but that the problem is not severe enough to halt the processor.
To clear a minor fault, reset individual bits on the status displays where the minor error bit is displayed. If you are unsure where the minor error bit is displayed examine the minor fault table.

Clear Major Fault
A major fault halts the processor. You have to clear a major fault before the processor can continue to run the current program.
Warning! When a processor faults, you must find and correct the underlying cause of the fault before attempting to clear the fault. If you do not find out what is causing the fault, the processor may behave unexpectedly.

Tip
Interrogate the status file when the processor faults to determine the cause of the error. A quick method to call the status file when the processor has faulted is to click the drop-down arrow to the right of the Operational mode listbox in the online bar. Then click Goto Error. You can clear the error from the status file.
After making sure that the condition that resulted in the error has been corrected, use either method below to clear a major fault:
1 From the Comms menu, click Clear Fault.
2 Click the Clear Major Errors button on the PLC-5 Status - Errors Tab.

Alternate Hardware Method
Turn the key switch on the PLC-5 processor from REM to PROG to RUN.
Rockwell Software Inc., 1997, 1998, 1999, 2000

I've been able to clear the crash log on most 5's just by using Logix to download the log. There is one I have, however, that just refuses to clear. The processor is still running, and has been for years, just with a crash-log present.

Lancie - The crash log on PLC5's isn't a fault status, it's an actual dump of information (sort of like a core dump) of the processor state in the event a major shutdown fault occurs. One thing that can cause it is if memory becomes corrupt. Sometimes backplane problems can also cause one to be written.

It stays permanently inside the PLC5 memory until cleared, or the memory is completely wiped.

RD,

Where is the crash log located in the PLC5 memory? I cannot find any references to the crash log, or any information about it. Is this a later feature and one that is not present on earlier models?

From RSLogix 5 Help:

Crash Log Ex??? Don't ask me.

Mickey,

That Crash Log message is not in my Help file. The crash log feature must have been added after RSlogix5 Version 4.10. This is the first I have heard of it, but then I am not exactly up-to-date, neither in knowledge or age.☯

Lancie1 said:

Mickey,

That Crash Log message is not in my Help file. The crash log feature must have been added after RSlogix5 Version 4.10. This is the first I have heard of it, but then I am not exactly up-to-date, neither in knowledge or age.☯

Click to expand...

Ditto!!
I have version 7.10. I heard it talked about here by a couple of the AB guys but never had a need to access it myself.I guess only
AB would know what it means.

User access to the crash log was added in I believe Version 6 of RSLogix 5.

Release Notes

All versions of the CPU can generate a crash log, prior to the user access, it was only retrievable by Rockwell (or with a Rockwell provided utility).