This read-write floating-point object sets the high-water-mark Not Corrected Blocks Error Rate above which the terminal raises a wvLinkNCBLERAlarm, indicating the link's forward error correction is failing to repair a rising share of errored blocks. An administrator watches this threshold because uncorrected blocks translate directly into data corruption reaching the end user, unlike blocks the FEC manages to fix. For example, an NCBLER alarm firing on a link that previously ran clean could point to a FEC engine or modem fault rather than simple RF fade.