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Entry type: FAQ Entry ID: 24845198, Entry date: 03/14/2019

What are the requirements for online delta loading in WinCC?

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Notes for successful online delta loading.

Refer also to the general notes in the WinCC Information System (Entry ID 109762744) under "Working with WinCC > Working with projects > Create and edit project > Online delta loading"

Basic requirements for delta loading

  1. Project consistency
    The projects on the configuration station and the Operator Station must be consistent. This means that the WinCC projects on the configuration station and on the Operator Station were identical before making the changes. For this you must have copied the WinCC project using the "Project Duplicator" tool. Notes on the topic of "Project Duplicator" are available as follows:
    -- in the WinCC Online Help (Entry ID 109762744) under "Working with WinCC > Working with Projects > Duplicating and Archiving Projects" or "Configurations > Redundant Systems > WinCC Redundancy"
    -- and in Entry ID 22821109
  2. Delta Loading is switched on
    Make sure that Delta Loading has been reset and switched on before making the first change on the configuration station.
  3. The Operator Station can be reached in the network from the configuration station
    Check whether there is a working network connection between the configuration station and the Operator Station. You can use the ping command for checking the network connection - see Entry ID 22132850
  4. Adequate access permissions
    Has the current user of the configuration station sufficient access rights for write access to the Operator Station? For this you check the network drive releases on the Operator Station.
    When using Microsoft Windows XP, the write access right must be set "explicitly" for the network drive release. The user group "Jeder" is only an example.

    Fig. 01

  5. The Operator Station is displayed in the "SIMATIC Shell" of the configuration station.
    Make sure that the Operator Station is displayed in the SIMATIC Shell of the configuration station. If multiple network cards are being implemented, select the network card that is to be used for the Online Change Load - see Entry ID 18967416.

    Fig. 02

Further Requirements
Also note the following:

  1. Delta loading is only possible if Runtime is activated on the corresponding computer.
  2. Each OS station must have been completely downloaded at least once beforehand.
  3. The requirements for a complete download (network settings, assigned user rights, etc.) must also be fulfilled for the delta loading. (See Entry ID 16827826)
  4. The licenses installed on the Master OS and on the Standby OS must cover the configured changes.
  5. Only the required licenses are on the computers. If necessary, you should delete surplus licenses.
  6. You are not to make any changes directly on the OS.
  7. Remote access to the computer must be configured correctly. (See Entry ID 78463889)
  8. If the "reset_wincc.vbs" script has been used on one of the computers, you have to restart all the computers concerned otherwise there might be inconsistent states.
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