Bulletin 77-03:On-line Testing of the Westinghouse W Solid State Protection System (SSPS)
NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT WASHINGTON, D. C. 20555 IE Bulletin 77-03 Date: September 12, 1977 ON-LINE TESTING OF THE WESTINGHOUSE W SOLID STATE PROTECTION SYSTEM (SSPS) Description of Circumstances: Westinghouse has recently reported that operation of the safeguards actuation block/reset circuitry is not being verified during the periodic semi-automatic logic testing of the Solid State Protection System as required by licensees technical specifications. Even though this portion of the logic system is tested prior to initial plant operation, circuit failure during operation is undetectable. Consequently, if any part of this circuitry fails, safety injection could not normally be reset and/or blocked. Resetting and blocking of safety injection signals are necessary for switchover to the recirculation mode of operation during accident conditions. The enclosed W Technical Bulletin NSD TB-77-11 was sent to affected Westinghouse plants notifying them of the problem and of the corrective action necessary to resolve the issue. The technical bulletin provides detailed information to augment established on-line test procedures. The method has been confirmed recently by successful verification tests of the WSSPS at both W Nuclear Instrumentation and Control Division (WNICD), Hunt Valley, Maryland, and North Anna Nuclear Station. Action To Be Taken By Licensees and Permit Holders: For all W Power Reactor Facilities with an operating license or a Construction Permit: 1. If your facility utilizes or plans to utilize the WSSPS, describe what action you have taken or plan to take to assure adequate periodic testing of all portions of the system. Further information regarding the necessary periodic testing procedures can be obtained from Westinghouse Nuclear Energy Systems in Monroeville, Pa. . IE Bulletin 77-03 Date: September 12, 1977 2. Report to this office in writing within 45 days for facilities with an operating license and within 60 days for facilities with a construction permit, your plan of action with regard to Item 1. Approval of NRC requirements for reports concerning possible generic problems has been obtained from the U. S. General Accounting Office. (GAO approval B-180225 (R0072, expires 7/31/80. Enclosures: 1. Extract from W Technical Bulletin NSD TB 77-11 Entitled: Periodic Testing of Safety Injection Reset Timing Circuit 2. List of IE Bulletins Issued in 1977
Page Last Reviewed/Updated Tuesday, March 09, 2021
Page Last Reviewed/Updated Tuesday, March 09, 2021