What was found
PILOTS REPORTED GENERATOR NO.1 FAIL IN FLIGHT APPROXIMATELY 10 MINUTES AFTER TAKEOFF AND RETURNED TO THE FIELD, UNEVENTFUL LANDING. NO.1 ENGINE DRIVEN GENERATOR FEEDER CABLE PASS-THROUGH IN LH PYLON WAS FOUND MELTED. DAMAGE FOUND ON POSITIVE AND NEGATIVE FEEDER CABLES ON BOTH THE ENGINE SIDE AND AIRFRAME SIDE CABLE RUNS. THE ENTIRE GENERATOR CABLE ASSEMBLY FROM THE LH POWER DISTRIBUTION BOX TO THE NO. 1 GENERATOR REQUIRES REPLACEMENT. PERFORMED CONDUCTIVITY SIGMA TEST OF SURROUNDING PYLON STRUCTURE FOR HEAT DAMAGE, FOUND THE TERMINAL MOUNTING PLATE AND SHUNT ANGLE TO BE OUTSIDE THE EXPECTED CONDUCTIVITY RANGE PROVIDED BY THE OEM.