This sets the per-minute count of BTUs discarded due to bus errors (transmission or parity errors on the Cell Bus) that this card must detect before it raises a trap, with zero disabling the check entirely. Because these are outright bus errors rather than resource exhaustion, a low threshold here is an early warning of a failing backplane connector or a marginal card seating in this specific slot. A technician troubleshooting intermittent card resets might drop this from the default down to 5 to get paged the moment bus errors start climbing instead of waiting for a card failure.