As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LEFT GENERATOR DROPPED OFF LINE DURING TAKEOFF ROLL AT APPROXIMATELY 30 KNOTS. ABORTED TAKEOFF AND RETURNED TO THE GATE. MAINTENANCE FOUND REGULATOR FAULT AT GENERATOR CONTROL UNIT. REPLACED THE LEFT VOLTAGE REGULATOR, OPERATIONAL CHECK NORMAL.