This enumerated bitmap value preserves which of this PSU's configured thresholds, across temperature and the tracked rails, were being exceeded at the moment this historical sample was captured. This lets an admin reviewing a past fault on this PSU confirm exactly which threshold condition, out of the several tracked in this row, was active at that specific historical timestamp. An archived sample tied to a documented fault might show a nonzero bitmap corresponding to a specific crossed condition such as output-12v-low at that time.