What was found
(CAN) THE NR 2 GENERATOR CAUTION LIGHT ILLUMINATED ON CAWS PANEL. EIS INDICATED THAT NR 2 GENERATOR HAD COME OFF LINE.THE PILOT THEN RE-SELECTED GENERATOR SWITCH TO ON POS,&HAD SAME SEQUENCE OF EVENTS OCCUR AGAIN. NR 2 GENERATOR WE AS LEFT OFF LINE FOR REMAINDER OF FLT. GENERATOR BRUSHES WERE REMOVED, & INSPECTED BY MAINTENACE STAFF. BRUSHES WERE FOUND TO HAVE WORN BEYOND SERVICEABLE LIMITS. ONE BRUSH WORN TO POINT WERE CONTACT NOT OCCURRING WITH ARMATURE:THE GENERATOR PREVIOUS INSTALLATION ON A/C REMOVED DUE TO (4) PREMATURE FAILURES OF BRUSH ASSY.THE CURRENT GENERATOR INSTALLED AS "NEW". IS 1ST SET OF BRUSHES TO FAIL ON INSTALLED GENERATOR. MAINTENANCE STAFF HAS NOW IMPLEMENTED.