What was found
(CAN) DURING CRUISE, THE INTERNAL COCKPIT LIGHTING WAS SWITCHED ON, OVERHEAD PANEL LIGHTS DID NOT ILLUMINATE. OVERHEAD PANEL LIGHT CIRCUIT BREAKER WAS OBSERVED AS TRIPPED. CIRCUIT BREAKER WAS RESET. A FEW MINUTES LATER A SUSPECTED ELECTRICAL BURNING SMELL WAS OBSERVED. F/A 1 WAS CONTACTED AND ASKED TO COME TO THE FLIGHTDECK. F/A 1 CONFIRMED THE SMELL AND STATED IT WAS STRONGER NEAR THE WARDROBE. QRH ACTIONS FOR FIRE/SMOKE UNKNOWN SOURCE WERE CARRIED OUT. A UNSCHEDULED LANDING COMPLETED. ENGINEERING INVESTIGATION REVEALED THAT THE NR 2 DC POWER SUPPLY EXHIBITED SIGNS OF OVERHEATING, AND DAMAGE DUE TO POSSIBLE EXCESSIVE CURRENT DRAW. UNIT ALSO HAD STRONG BURNED SMELL. THE NR 2 DC POWER SUPPLY WAS REPLACED IAW THE AIRCRAFT MM 33-10-00. (TC NR 20071001003)