The print device definitions you create in the Printer Catalog ( File menu > Printing > Printer catalog ) are located in the plotdev.bin file. This file is located in the system folder defined for the advanced option XS_SYSTEM.
The definitions in the system folder are accessible to all users. You can also save printer definitions in the current model folder or in the project and firm folders, and in a folder indicated by this advanced option. Tekla Structures searches first for plotdev.bin in the model, project and firm folders, then in the folder indicated by the advanced option XS_DRIVER.
This advanced option is system specific and is read from environment files. Generally, there is no need to modify system-specific settings. Do not modify them if you are not an administrator.