# Connection of Different Preprocessing Files

In the image above you can see for the connection '*Perpendicular from the rear*' a different situation. There are three entries there:

* (current lead file): This is again the case where the striking wall and the struck wall have the same HRB lead file, namely exactly the file that is currently being edited. The file currently open here is the file I\_Dietrichs\_HRB14, a lead file for interior walls.
* A\_Dietrichs\_HRB12: In this case the connection of the current HRB lead file to a wall with the lead file 'A\_Dietrichs\_HRB12' is defined. This is a lead file for an exterior wall.
* A\_Dietrichs\_HRB14: In this case the connection of the current HRB lead file to a wall with the lead file 'A\_Dietrichs\_HRB14' is defined. This is also a lead file for an exterior wall.

By double-clicking one of the lead files the dialog box with which you can define this connection opens directly. By double-clicking the entry '*Perpendicular from the rear*' a parent dialog box opens with which you can create new connections of this type and make other relevant settings:

<figure><img src="https://1294550180-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F0t0AJ2HDudwBgiGFR59Q%2Fuploads%2FUEQPIwIZTw3WPV2UGguN%2Fgrafik.png?alt=media&#x26;token=8bb86536-dfd3-475b-81d3-5c0fcdb445c1" alt=""><figcaption></figcaption></figure>

### NOTE:

Connections between files with different HRB lead files are always made from the striking wall.

The upper list enumerates all connections in which the current file connects to another lead file. The current file is therefore the striking wall there, and these connections can be edited.

The lower list enumerates all connections in which the current wall is struck by another lead file. The current wall is therefore the struck wall there and these connections cannot be edited. To edit them, open the corresponding other file, which then becomes the striking wall.

The situation in the HRB interpreter is noteworthy when there is a connection in which the current file connects to another file and no specific connection was defined for that case. For such cases you can mark one of the existing connections so that it will be used:

With the three small buttons at the bottom of the dialog box you mark the connection selected above so that it should be used either for connections with exterior walls, interior walls, or walls without an HRB lead file. In the example above the connection '*current lead file to -- A\_Dietrichs:HRB14*' should also be used for other exterior walls for which no dedicated connection has been defined.
