Insert External Reference

    Ribbon: Insert – Reference >  DWG Reference

   Menu: Insert –  DWG Reference

   Toolbar: Draw –

Command line: ATTACH, XA, XATTACH

External references allow you to add information from other drawings to the current document. It is possible to insert several external references into one document. Conversely, the same document can be used as an external reference in several other documents. External references can contain inserted external references. When you add an external reference, all external references inserted in it will also be displayed in the current drawing.

External references can only link external documents to the current document. The objects placed in the drawing file with external references are displayed in the current drawing with other objects in this drawing, but they are not added into the drawing. The external reference is a kind of label that indicates the path to an external drawing. When you add the external reference, its objects are not copied into the current drawing or loaded from the external reference file every time you open basic drawing or restart the external reference. Any changes made to the external reference will be also displayed when you open the basic document or restart an external reference.

When you insert an external reference into the drawing, the file size of the current drawing is increased slightly.

Since the external references are always kept in separate files, then the exchange of drawings should convey not only the basic drawings, but all drawings which are referred to.

You can specify different types of external reference: attachment into the drawing and overlay on the drawing. When you insert an external reference using an attachment type, then all external references inserted into the drawing are added to it. If you choose an overlay type when you insert an external reference, then external references inserted into it are ignored. Overlay external references are used when the information provided by an external reference in the current drawing is not needed for later use of this drawing as an external reference.

There are three ways to save path information with an attached reference:

·         Full (absolute) path is a fully specified folders hierarchy that locates the file reference. This is the most precise  but the least flexible option. The full path includes a letter of a mapped local hard drive, a website URL, or a mapped disk letter on a network server.

·         Relative path is a partially specified folders hierarchy that is defined relative to the current drawing (the folder in which it is stored). If you choose this type, it is necessary to save the current drawing. For the enclosed reference the relative path specifies a reference location, which can be the current open document. This is the most flexible option, and enables you to move your current drive to a different drive that uses the same folder structure. If the file that is being referenced is located on a different local hard drive or on a network server, the relative path option is not available.

Rules of making relative paths:

When a drawing containing external references is saved or replaced to other hard drive, computer or network server it is required to change all relative paths according to a new location of drawing or change location of external references files.

·         No path – not specify a path to an external reference. Specifying the No path option is useful when moving a set of drawings to a different folder hierarchy or to an unknown folder hierarchy. If a path for an external reference is not specified, the program searches for the external references in a current folder of a main drawing.

To insert an external reference into the drawing, specify the path and file name in the opened External Reference dialog box: To insert an external reference, the External Reference dialog box opens, which is a standard Windows file open dialog in which you should specify the path and file name to insert as an external reference. To specify several files at once for simultaneous insertion, select them with the CTRL or SHIFT.

Select the necessary external reference and click Open. The External Reference dialog box will open.

Parameters:

The presence of xrefs in a drawing is shown by an indicator appearing in the status bar:

If in the course of work the xref file was changed in a third-party program, a warning will appear, and the indicator will change its appearance:

The indicator’s context menu allows you to open the External References dialog box or Refresh External References of the drawing:

If the xref file was not found, a corresponding message appears and the status bar indicator button changes color to red:

XREFNOTIFY variable allows you to disable notification about changes in xref files or change notifications appearance:

0 – disable notification about changes in external references.

1 – display notifications in the form of dialog boxes.

2 – display notifications as pop-up messages near the status bar.

The time after which external references are checked is set by the XNOTIFYTIME variable (in minutes).