Headquarters Daily Report OCTOBER 19, 1998 *************************************************************************** REPORT NEGATIVE NO INPUT ATTACHED INPUT RECEIVED RECEIVED HEADQUARTERS û REGION I û REGION II û REGION III û REGION IV û PRIORITY ATTENTION REQUIRED MORNING REPORT - REGION II OCTOBER 19, 1998 Licensee/Facility: Notification: Carolina Power & Light Co. MR Number: 2-98-0047 Robinson 2 Date: 10/19/98 Hartsville,South Carolina Dockets: 50-261 PWR/W-3-LP Subject: REACTOR/TURBINE TRIP DURING SURVEILLANCE TESTING Reportable Event Number: 34925 Discussion: On October 17, 1998, at 2:10 a.m., Robinson Unit 2 experienced a reactor trip from approximately 56% power. The reactor trip resulted from a turbine trip caused by high steam generator levels. During a power range nuclear instrumentation (NI) surveillance, control power fuses blew on NI-44. A turbine runback occurred from 100% to 56% power. Pressurizer PORVs cycled several times during the runback when steam dump valves to the condenser failed to open automatically. Operators switched the steam dump controls to the steam pressure mode which caused the steam dump valves to open. This caused steam generator levels to swell ultimately resulting in a turbine trip which caused a reactor trip. The high steam generator level also caused feedwater isolation tripping both main feedwater pumps and causing the three auxiliary feedwater pumps to start. Following the trip, source range NI-32 did not function as expected. All other safety equipment functioned as expected. Operator response to the transient appeared to be appropriate. The NI-44 power supply was determined to be the cause of the fuse failure and was replaced. The cable and connector on NI-32 was replaced. The steam dump comparator/control module had failed and was replaced. The reactor was taken critical October 18, at 12:49 p.m. and the unit was placed on line October 18, at 5:30 p.m. The plant is currently at 100% power. Regional Action: Upon notification of the event, the senior resident inspector responded to the site. The resident staff followed up on the licensee's event recovery activities. Contact: G. MACDONALD (404)562-4543 _