FME Form: 2026.1 BETA
FME supports conversions between coordinate systems using different datums. Many datum transformations are not mathematically definable and require the use of grid of shifts. If you attempt to make a datum transformation of this kind without the appropriate grid shift file in place, FME will abort the translation.
The FME installation includes a configuration file for managing the use and location of grid shift files.
These files are found in the Reproject folder in the FME installation folder. For example, the file Nad27ToNad83.gdc includes file paths to both the Canadian and US grid shift files for the NAD27 <-> NAD83 transformations.
FME Reprojection Grid Add-on
The FME Reprojection Grid Files add-on contains reprojection grid files that are not included in the FME Form installer. To access these additional Reprojection Grid Files, visit the FME Downloads Page. After specifying your platform and FME version, locate the applicable download under FME Reproject Grid Files. There are two options for installing:
Using the Installer
On Windows, download and launch the executable file to install the FME Reprojection Grid Files add-on.
Extracting the Zip Archive
A zip archive is available on non-Windows platforms, and on all platforms for versions of FME older than 2026.1 BETA. Download the Reprojection Grid Files zip archive, and extract the .zip into the root of your FME Form installation directory. You must have write permission in that directory.
Installing Additional Grid Files
If you need grid shift files that are not included with an initial installation or the FME Reprojection Grid add-on, you can install them separately. For more information, see To add a grid shift file to FME.