Control.com - Nerds in Control

Dear All,

We are facing frequent Profibus failures with ET200S IM modules of Siemens. They are connected to a S7-400 CPU on a machine. When it fails, the BF and SF LEDs are flashing randomly, and there is no Profibus communication with the module anymore. Most of the time, we are able to make the module alive again by only disconnecting and connecting the power of the module. If this also does not help, then we are changing the module with a new one.

I also have one more observation, the faulty modules are always with the following MLFBN numbers:
6ES7151-1AA02-0AB0 or 6ES7151-1AA03-0AB0.

We also have new machines with 6ES7151-1AA04-0AB0, they still didn't create any problem. Can it be because of this version problem? Or is there any other problem and solution know for this issue? I am waiting for your valuable helps. Thanks and regards...

Canan

Hello,

6ES7151-1AA02 and 6ES7151-1AA03 are defective in mid-time: we have large experience with a customer that have in plant about 30 IM, one to one he has decided to change with -1AA04 one. We have gotten the random failures that are difficult to get out: so I suggest you to change them with the newest 1AA04 one.

Gabriele

My customer has the same problem on the 1AA04.Several units destroyed the last three years, three units just the last three months (twice the same address unit). Blinking SF/BF.

Hello
in reply to micapp:

We have installed several hundred of 1AA04 units,without any failure: I don't tell you that are securely good, the bad batch product or some units could be present, but I think that the 1AA04 units are much stable: as a proof the time between series 2 to 3 was a mid time of years, the time between 3 to 4 was a shot time of months, and now until siemens don't release the 5 version I think the release 4 is pretty stable.

For better understanding of problem could you reply with the mounting and application of units?

Thanks, regards
Gabriele Corrieri

Hello Dear All,
In our plant also there was frequent failure of 1AA02. Then we changed to 1AA03. Failure rate was only reduced. But not completely vanished away.

After consulting with experts we checked our earthing network. The earth resistance was not good. We improved the quality of earthing net work (separated power and control grounding network). Later no more failure of modules is happened.

Thanks,regards,
Mark

Hi All,
After searching the possible reasons from internet, I have decided to change all modules with version 4. After changing, there is no more failure anymore. Meantime, our grounding and earthing values are nearly perfect. I have read somewhere that the cards with revision 3 and older are faulty. It was suggested to replace them with version 4 and newer. After replacement, I didn't face any problem.

Hi All,
We've had several failures on the 1AA03 over the last year and a couple of RS 485 Repeaters. Ran across this post looking for replacements. I've compared prices between the series 3 & 4 and the 4 is less expensive for new and repair. Is this unit a direct drop in or does something additional need to be done? I thank all of you for this important information.

Bill S.

Hi Bill,
You can simply replace the module with the version 4. No need to do any software-hardware change.

Hello

Not true: you must change your hardware config, compile it and transfer it to cpu.

Gabriele

Hi Gabriele,
It will work also with the current HW configuration without any problem. This had been tried by me for 100's of times for ET200S modules with different versions.

Hello

I'm not sure but after your confirmation I think that the change in HW config must be necessary from release 2 to 3, we have changed always the hw configuration with a module change (any type).

Gabriele