Is there a way to automatically recover from a fault in Micro 800 Plug-In module?

I am getting a fault from a plug in module that is causing the PLC program to halt. When I manually clear the fault and switch back to RUN, everything is OK. Is there a way to do this automatically?

I'm not sure I understand your problem. What causes the Fault?

I would be trying to prevent the FAULT condition, instead of finding a way to automatically clear the fault.

I appreciate your concern, and we are actively researching potential causes of the fault, however, it only occurs once in a blue moon, so this is challenging.

My question really is, what options do I have with the Micro800 based design to sense, analyze, and deal with faults programmatically? Can I sense a fault and then log any relevant data before the PLC jumps me out of my program? Can I force the PLC to reset? Is there a watchdog function in the PLC?

I am assuming you have CCW software? Look in the Controller manual and start at page 135 it will tell you how to log, read, troubleshoot, faults.

This will be your best solution.

Good Luck

David,
Can you tell me the document number of the manual that you are referring to? I did not find anything at page 135 of the Micro820 Control Users Manuals (2080-um005_-en-e.pdf) or the Micro800 Programmable Controllers General Instructions manual (2080-rm001_-en-e.pdf)
Thanks.

Never mind... I found it right there on page 135 of Micro820 Control Users Manuals (2080-um005_-en-e.pdf).

David. Thanks for the advise. The section on error codes is useful information on dealing with things manually (which is what we are currently doing), however, it doesn't offer any guidance or direction on what can be done from within the application code.

What I want to do is add logic to:
1. Sense and trap the fault and save information in retentive memory which can be used after the program resets to log an alarm.

2. Reset the PLC from within the ladder logic code. Unfortunately. it does not look like the existing watchdog timer can be used as a watchdog reset function. Is there any way to force the PLC to reset from within the ladder logic code?

I have not used this feature, but you should be able to connect CCW to the controller and once connected under the Device tab, you can select diagnose and see what comes up. You may need to stay connected to controller and let run in debug mode for extended time.

I don't think you will be able to reset fault from ladder as this would be a very bad safety hazard.

I am by no means an expert on this equipment, so someone else may be able to provide more help.

I know that other AB PLC/PAC’s you can manipulate certain types of errors so that they don’t halt the processor however I don’t know if that can be done in a Micro800. There is a startup configuration where the processor will clear any faults on startup (unless it’s a hard failure) but that would require that the Micro be power cycled. If you really wanted to you could have another PLC messaging to it on a regular basis and if it stops answering back the other PLC could be setup to power cycle the Micro but that’s a lot of overkill for something that hopefully you can solve.

I think I'm coming to the conclusion that my options are severely limited. An external watchdog reset timer in the form of a timer relay that gets periodically reset by the PLC is likely the only option I have. Unfortunately, it is not practical for this product.

Thank you both for your responses.