I haven't dropped an SD card in the 2330L yet, but looking at event setup for an SD card, it has the same option for limiting recording size as the 2132L - which causes old video files to be deleted and therefore preventing the card from filling up:
"Total cycling recording size: [Empty Size Field] Mbytes [200~2000000]"
I typically leave a GB or two free, to be safe. Same for the 942L, which also allows cycling.
I view the SD card as a last-resort backup, recording 24/7 in case D-ViewCam, and ftp video writes to a hard drive, each fail. And it's a good practice to let the SD card fill up and cycle to understand how many days of storage are available for the selected video resolution (i.e., to understand how much time is available to retrieve files, just in case those files on the SD card are really needed). But if the 2330L really is not cycling, then SD card functionality is out the window.