Hi all,

I work in a refinery, maintain/make change of existing APACS system. I felt APACS is kind of reliable. But recently, when I try to make change on one function block, it does not allow me to download the change with a popup screen saying "Segment invalid (corrupt Local Linkage Table).

Later, I found errors with ACM, one is "Memory Corrupted", another is "Redundancy Disabled, because ...". Both lights on the module were red; the system kept running for quite while.

The weekend, I cleared and downloaded the program - errors were gone, still I can not make change on the function block. Monday the errors came again, and even faulted ACM modules.

Other information: memory usage 78.1%, B side IOBUS error.

Thanks for any help and

Best Regards,

DZ

Hello RJP,

Thanks for your response. System Service Code 28, Error Code 20 on one ACM, and System Service Code (27), Error Code (20) on the other one. Meanwhile we have B side IOBUS error 29 (11) of a rack.

We disconnected batteries for both modules, pull them out, and re-downloaded the same program during the weekend. This morning when fault occurred, we downloadedan older version. Right now, it seems fine.

I just wonder the reasons thatcaused the configuration corrupted. Program problem - due to the change I made? Once we downloaded the older version, could it be solved?

By saying "...Siemens Technical Support to locate the corruption and offer a solution", you mean locate the corruption in the program, or could it be some other reasons?

Thanks,
DZ

RJP,

It's possible thatSSC28 EC20was the same module, I did not recall. We have one ACM module changed out this April, maybe it is the time for the second one.

The question is after we downloaded the old version program for two days, it work well. I suspect that the changes recently made fault the ACM, or the configuration file somehow got corrupted.

After downloading the latest version (with change),errors weregone, but I can notsave the change ofone user defined function block. Later when the refinery wenton production, errors cameup,OK lights were red, but it still kept running fora while (not fault immediately).

Anyway we have ordered Siemens Engineers coming in thisFriday, I willlet you knowwhat they find. Besides, we will have them check errors of IOBUS, and rest of the system.

Thanks and Regards,

DZ

RJP and all,

A SiemensTIC wassetup for us, and I sent two versions of configuration files. The configuration file (program) went through two types of configuration check, none corruption was found. ACM module or Modulerac was suspected to be failing, but this can not explain why the older version still running. After downloading it to a controller, they can duplicate the problem I had - can not save the change in the function block - a pieceof configurationcorrupted.The corruption was fixed through exporting / importing.

The Siemens Field Engineer opened the ACM cover, a lot of bubbles on the chips (seeattachedpicture)because of heating. Besides we used up to 78.x% of memory, and it is recommended to have 20% ~ 25% spare memory for online edit. Still we are not sure which reason causing the corruption, I would like to summarize it as: "online change on a failing ACM module with limited resources".

I would say Siemens TIC is very helpful. And also this forum is great. I am pretty new in APACS programming. I am going to utilize this site for my questions.Appreciate yourreview andresponse.

DZ

New question published by DcsEng is split to a separate thread with the subject Issue of communication Between QuadLog CCMx controller and FESTO CO 950.

Best regards
Min_Moderator