As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT NR 1957 - IAH - ALL THREE BUS TIE BREAKERS TRIPPED AND THE SECOND OFFICERS FAULT ANNUNCIATOR INDICATED A PHASE UNBALANCE WHILE EN ROUTE TO IAH. THE AIRCRAFT LANDED WITHOUT INCIDENT. MAINTENANCE FOUND THE BUS PROTECTION PANEL AT FAULT. THE BUS PROTECTION PANEL WAS REMOVED AND REPLACED. THE ENGINES WERE RUN AND OPERATION CHECKED NORMAL. (M)