This sets the lower current threshold, in mA, below which the modem raises an LNB under-current alarm, typically indicating the LNB has lost power or failed open. Because a dead LNB draws essentially no current, this low-side threshold is often the very first symptom an admin sees of a completely failed receive chain, before any downstream demodulator-lock alarm even triggers. Setting this to 50 mA means any reading below that flags a likely LNB failure, prompting a truck roll before the customer even notices lost signal.