COMMERCIAL GRADE ITEM (CGI) DEDICATION OF MDR RELAYS FOR NUCLEAR SAFETY-RELATED APPLICATIONS

MDR relays manufactured by Potter & Brumfield (P&B) have been used in various safety related applications in commercial nuclear power plants . These include emergency safety features (ESF) actuation systems, eme rgency core cooling systems (ECCS) actuation, and reactor protection s ystems. The MDR relays manufactured prior to May 1990 showed signs of generic failure due to corrosion and outgassing of coil varnish. P&B h as made design changes to correct these problems in relays manufacture d after May 1990. However, P&B does not manufacture the relays under a ny 10CFR50 Appendix B quality assurance (QA) program. They manufacture the relays under their commercial QA program and supply these as comm ercial grade items. This necessitates CGI Dedication of these relays f or use in nuclear-safety-related applications. This paper presents a C GI dedication program that has been used to dedicate the MDR relays ma nufactured after May 1990. The program is in compliance with current N uclear Regulatory Commission (NRC) and Electric Power Research Institu te (EPRI) guidelines and applicable industry standards; it specifies t he critical characteristics of the relays, provides the tests and anal ysis required to verify the critical characteristics, the acceptance c riteria for the test results, performs source verification to qualify P&B for its control of the critical characteristics, and provides docu mentation. The program provides reasonable assurance that the new MDR relays will perform their intended safety functions.