What was found
ON DEPARTURE, THE COPILOTS PANEL WENT DARK, NO INFORMATION DISPLAYED. LEFT GENERATOR HAD FAILED AND A NUMBER 17 OF CIRCUIT BREAKERS TRIPPED. PILOTS REFERRED TO QRH AND RETURNED TO DEPARTURE SAFELY. DURING THE INSTALLATION OF STC STC02507LA , FAILED TO ACCOUNT FOR CLEARANCE BETWEEN UPPER TANK SYSTEM AND EXISTING AIRCRAFT WIRING BUNDLE, OVER THE COURSE OF THE LAST 567 CYCLES (SINCE INSTALLATION)CHAFING OCCURRED TO A POINT WHERE ON 07/09/2019 A SELECTION OF 8 GAUGE WIRES THAT INCLUDE A/C FLOW CONTROL VALVE, A/C REGULATOR VALVE L&R, PRIMARY TRIM MOTOR HEATER, RAM AIR VALVE, L/H ENG IGN, R/H ENG IGN, R/H FUEL FLOW, R/H ENG ANTI ICE COWL, APU DOOR CONTROL, R&L HEAT EXCHANGERS, PHASE A&C GROUNDED OUT AND CAUSED A PARTIAL ELECTRICAL FAILURE. SOME ODOR WAS NOTED AFTER LANDING AND CHARRED WIRE BUNDLE NOTED.