AT 1:30AM THE ELECTRICITY AT THE #3 HOIST KICKED OUT WHILE THE HOIST OPERATOR WAS MOVING CAGES, HE RESET THE ELECTRICITY AND STARTED TO MOVE THE CAGES WHEN IT KICKED OUT AGAIN. HE NOTIFIED THE CREWS UG & CALLED HIS SUPERVISOR. A CONTROLLER COIL ASSEMBLY WAS FOUND TO BE FAULTY & IT WAS REPLACED. THE CREWS WERE THEN HOISTED OUT FROM UG & TESTS WERE DONE TO PREVENT A RECURRENCE.