Hi,

Recently, we have an increasing number of cases where 400 or 300 CPU's are unable to be stopped via the Step 7 software. (not via 'operating mode' and not via downloading the HW-config)

When downloading the hardware, we get the pop-up that says that the PLC will need to be stopped. When we click 'YES', the progress-bar stands still for about 30sec , and then we get a pop-up which states "The PLC cannot be stopped. Check the diagnostic information on the CPU for more information." The CPU diagnostic buffer does not show anything, however. It is possible to download FC's in the PLC, and monitor them, but the PLC cannot be set to Stop for some reason. I never encountered such thing in my 20 years of programming step 7.

We tried this with a PG via ethernet connection, and also via MPI, neither work.

To fix this, we have to manually set the switch to stop on the CPU. Sometimes, even then it's not possible to download the hardware. Then we have to switch off the power supply of the PLC.

As said, more and more PLC's begin to have this same issue. Is this a bug in the Step 7 software? Does someone have a similar experience? Is there a solution?

We use following CPU's:

- 6es7 317-2FK14-0ab0 (about 100 of them)

- 6es7 416F-2FN05-0ab0 (more than 60 of them)

We use following Step 7 version:

- V5.6 + SP2, revision K5.6.2.0

We first had this issue about a month ago, now we've have the same issue on about 5 PLC's (that we know of). 

Hi,

I have tried with many different PC's. The all have the same Step 7 version.

We also tried with an old laptop via MPI, with Step 7 V5.6 SP1 + HF5, and it has the same problem.

I will install HF3 on 1 PC and when we encounter this problem again, I'll try it out.

To be continued