You are here: FME Workbench > User Interface > FME Options > Coordinate Systems

Coordinate Systems

Select Tools > FME Options and click the Coordinate Systems icon.

How to determine which grid shift files are installed

A number of grid shift files are included when you install FME. For details, see Included Grid Shift Files.

How to maintain and edit grid shift files

This option allows you to maintain and edit grid files. You can manage the grid files by selecting a file and clicking the Edit button (or, simply double-click the file). The dialog that appears lists one or more grid shift files:

Add button: Opens a file browser so you can select a new file and add it to the list.
Remove button: Removes a selected file.

Note: We recommend that you make sure that the grid files you need are in the list, and that you remove any files that you do not need. See NAD27/NAD83 Datum Shifts in U.S. and Canada on FMEpedia for information on why it is important to configure FME to use the correct files.

Fallback Datum: Select the datum to use if the selected grid file does not cover the area of your input data. Fallback datums are listed in individual .gdc files, which you can open with any text editor.
Move Up and Move Down buttons: Note that these buttons will rearrange the list, but they do not determine the order of precedence of the grid files.

Click OK to apply changes, and Cancel to discard changes.

WARNING!
If you add a file, you are not copying the file – you are only pointing to the file’s location. Thus, if you delete a file from its original location, the entry you create here will point to a nonexistent file. Safe Software recommends that you copy each grid file to FME’s Reproject\GridData subdirectory before adding any files to your configuration.

How to add a grid shift file to FME

Follow these steps to install a grid file so that FME will recognize the file:

Copy the new file to FME's Reproject\GridData subdirectory.
Select Tools > FME Options and click the Coordinate Systems icon.
Select the applicable datum shift and click the Edit button.
A dialog displays the files already recognized by FME for the applicable datum shift. To include new files, click the Add button, browse to the applicable directory and find the file in Reproject\GridData subdirectory.
Select the file and click OK.

More Information

For additional information on grid shift files, see the Coordinate Systems section of this help file, or view these specific topics:

How FME Handles Grid Files

Included Grid Shift Files