frame, whereas the field IR scan shows a more isolated area
of elevated temperature. Remember that the IR camera is
recording surface temperature. IR is not measuring the actual
heat generated by the conducting components of the breaker,
but instead the camera measures the deflected and absorbed
temperature of the conductors through the breaker frame. The
lab test condition represents a balanced 3-phase 150 ampere
current, while the field test condition presents infinitely more
variables. So, some variability is to be expected.