Micrologix 1400 - error code 71h intermittent

[tkeel]

I have a micrologix 1400 that will fault out on error code 71h every once in a while, I am talking months in between fault.

Now, sometimes I can clear the fault and the processor will come right back up working, no problem, and now other times, it will come back up but no I/O modules working. I shut it down again, wait a little while, start it back up, and low and behold everything works again.

it is frustrating that it is so intermittent. Is there a way I can detect or catch what is causing the issue because it happens so infrequently?

TK

 

[Mickey]

See link below.

http://www.plctalk.net/qanda/showpost.php?p=233735&postcount=4

 

[tkeel]

Thanks Mickey.
Connections have been checked and rechecked. Modules reseated.

 

[Mickey]

Thanks Mickey.
Connections have been checked and rechecked. Modules reseated.

And the last part of that knowledgebase was surge protection for inductive loads.

 

[tomplc]

I have a micrologix 1400 that will fault out on error code 79h every once in a while.

 

[Mickey]

I have a micrologix 1400 that will fault out on error code 79h every once in a while.

From the manual...

xx79(1) EXPANSION I/O
MODULE ERROR
An expansion I/O module generated
an error.
Non-Recoverable • Refer to the I/O Module Status (IOS) file.
• Consult the documentation for your specific
I/O module to determine possible causes of
a module error.


(1) xx indicates module number. If xx = 0, problem cannot be traced to a specific module.

 

[Old No. 7]

Out of curiosity, what IO modules do you have connected to it?