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Entry type: FAQ Entry ID: 23933965, Entry date: 09/20/2006

Why can't you set up an online connection any more after installing STEP 7 version V5.4 with a PC/TS adapter?

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The table below contains notes and remedies for the case that you can no longer set up an online connection after installing STEP 7 version V5.4 with the PC/TS adapter, or if the online connection is interrupted after a short time.

No. Notes and remedies for setting up an online connection
1 We recommend that you first install the update SP1 (Service Pack 1) for STEP 7 version V5.4, because this updates the device drivers for the PC and TS adapters. We recommend installing the update in particular if you experience sporadic loss or breakdown of the communication connection, for example when monitoring variables (asynchronous jobs).
2 Please note that with STEP 7 version V5.4 there are higher hardware requirements for memory expansion. For STEP 7 version V5.4 in MS Windows 2000 and XP you need at least 512 MB RAM. For STEP 7 version V5.3 you needed at least 256 MB RAM.
  • STEP 7 V5.4:
    RAM: at least 512 MB (a main memory of at least 1 GB is recommended).
  • STEP 7 V5.3:
    RAM: at least 256 MB (a main memory of at least 512 MB is recommended).  
3 Check the virtual main memory. Increase the virtual main memory to at least 1000 to 1500 MB. More information on setting the virtual main memory in the various operating systems is also available in Entry ID: 20440472 (Notes on optimizing performance).
4 Please also refer to the note in the STEP 7 V5.4 readme file: "If there is failure/interruption of communication connections via PC adapter or TS adapter, check the settings of your computer's Power Management."

For this you go to the Control Panel and open the "Power Options Properties" dialog (Fig. 01) and in the "Power Schemes" tab you select the following settings for "Settings for Home/Office Desk power scheme":

  • Turn off monitor: "Never"
  • Turn off hard disks: "Never"

Fig. 01

Then click on the "Apply" button and acknowledge with "OK".

Notes on the versions:

  • Earlier versions of the PC and TS adapters (PC/MPI cable to the MPI connection via the COM interface of the PG/PC) can only be used for MPI connections and not for PROFIBUS connections (DP, Universal).
  • PC and TS adapters as from V5.0 can be used on MPI and PROFIBUS up to 1.5 Mbit/s.
  • The TS Adapter II can be operated on MPI and PROFIBUS up to 12 Mbit/s.
5 Another cause of the behavior described above could be that some files of the SIMATIC STEP 7 software are damaged or installation of the STEP 7 software was interrupted. In most cases, the repair function on the STEP 7 CD can be used to restore the software status on your PC.

More information is available in our FAQ "Is there a check list for implementing a PC adapter?" in Entry ID: 10420976 .

Connection setup,
Communication setup,
Test mode

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