Closeout of IE bulletin 85-02: Undervoltage trip attachments of Westinghouse DB-50 type reactor trip breakers

Technical Report · Thu Sep 01 04:00:00 EDT 1988

OSTI ID:6877245

Foley, W J; Dean, R S; Hennick, A

Documentation is provided in this report to close out IE Bulletin 85-02 on the subject of undervoltage trip attachments (UVTAs) of Westinghouse DB-50 Type reactor trip breakers (RTBs). The bulletin was issued to require the owners of Westinghouse operating power reactors to provide assurance that their DB-50 Type RTBs with UVTAs were operating properly, unless they had implemented the automatic shunt trip modification. Review of utility responses and NRC documents shows that the concern about unmodified RTBs applied to eight facilities. Evaluation of utility responses and NRC/Region inspection reports shows that reliability of UVTAs at these eight facilities is ensured by means of procedures, tests and schedules. Furthermore, the NRC regions verify that the recommended automatic shunt trip attachment has been or will be implemented at these remaining eight facilities. Background information is supplied in the introduction and Appendix A of this report.

• Research Organization: Nuclear Regulatory Commission, Washington, DC (USA). Div. of Operational Events Assessment; Parameter, Inc., Elm Grove, WI (USA)
• OSTI ID: 6877245
• Report Number(s): NUREG/CR-4935; PARAMETER/IE-170; ON: TI89001009
• Country of Publication: United States
• Language: English

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