The FX3U-32BL can be installed to the FX3G/FX3GC series.
After installation, select [Battery Mode: Use the battery] on the FX parameter window of GX Developer or GX Works2.

Please refer to the following manual for further details;
FX3G SERIES PROGRAMMABLE CONTROLLERS USER'S MANUAL(Hardware Edition)
9.3.2 Setting the battery mode
FX3GC SERIES PROGRAMMABLE CONTROLLERS USER'S MANUAL(Hardware Edition)
9.3.2 Setting the battery mode