What was found
(CAN) THE FLIGHT CREW REPORTED THAT THE PTU HYD POWER CB, L8 ON RT ESS BUS, POPPED. WHEN RESET BY MAINTENANCE THE CB POPPED AGAIN IMMEDIATELY. TROUBLESHOOTING FOUND THE POWER WIRE TO PIN A OF CONNECTOR PLUG 2921-P23 AT THE PTU SOLENOID VALVE WAS CHAFED TO THE BACKSHELL OF THE CONNECTOR PLUG AND WAS SHORTED TO GROUND. THE WIRE WAS REPAIRED AND THE ACFT RETURNED TO SERVICE. THE CAUSE OF THE CHAFING APPEARS TO BE THAT THE WIRE WAS GIVEN TOO WIDE A BEND RADIUS AT INSTALLATION.