Typical Fuel pumps run at 115VAC, 3 phase, and can draw up to about 3.45KW. (3450 W)
Just because a pump heats up internally does not necessarily trip respective circuit breakers in the cockpit. (A heating element on your stove top gets red hot without tripping a breaker). Usually fuel tank pumps are protected by thermal switches which are supposed to trip, as in the case when a pump is left running in a dry tank and overheats, etc... The question obviously is: Why did the Hydro-Aire pumps reach 1100 degrees without an automatic thermal cutout.
The Thai Airways B73-3 empty center tank explosion at the gate at BKK is believed to have been caused either by its pump overheating, or by arcing of electrical connections.