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
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