Omron NV Series Programming Manual page 222

Transferring and Copying Data Using SD Memory Cards (NV4W/NV3Q)
Should formatting ever prove necessary, download the SD Memory Card for-
matting software from the Panasonic website, and use the software to format
the card.
Note For details on formatting, refer to the documentation provided with
the formatting software.
Precaution for Correct Operation
If an SD memory card is formatted with the standard formatting utility provided
with a personal computer, its file system will not conform to the SD memory card
standard. Always use the formatting software provided by Panasonic.
Section 9-2
201