On Export back to AVEVA E3D™, for any member which has this Mark attribute set, the original imported Mark value appears again in the SDNF file. Thus you are able to spot any changes to the model. The AVEVA SDNF Import system, then allows you to modify the existing structure, rather than just replacing it with a copy. In this way, any drawings for example, which may have been produced between Export from and Import back to Model, retain their logical relationships to the steel members.

A member created outside Model does not have the Mark field set to be an AVEVA E3D™ internal reference number. The AVEVA SDNF interface would therefore know that it was importing a new element and would create it accordingly, whilst recording the external Mark number as well.

If SDNF detects that there are duplicate external mark numbers as it is preparing to export a model, the internal reference number is used in preference. The SDNF interface then has some chance of identifying the element if it returns from the external package. Refer to Issues Concerning Entity Comparison for further information.