Part 21 Report - 1995-190
Accession No. 9508240355 EVENT NOTIFICATION WORKSHEET Notification Time: 18 Aug 1995 1352 Facility: Watts Bar Unit 1, 2 Caller's Name: P. L. Pace Caller's Number: (615) 365-1824 Event Date: 16 August 1995 Regulation: 10 CFR 50.55(e) Description: Finding Identification Report (FIR) WBFIR930012307 was initiated, in part, to document potential deficiencies associated with uninspected vendor wired safety-related electrical panels. As part of the corrective actions to resolve the FIR condition, walkdowns of previously uninspected vendor wired safety-related electrical panels were to be performed. Those walkdowns have been completed. A review of work implementing documents generated to resolve deficiencies identified during the FIR walkdowns revealed four categories of deficiencies: (1) terminal blocks; (2) loose connections; (3) cables/conductors; and (4) cable/conductor insulation gaps. Category 1, 3, and 4 deficiencies have been evaluated as not having an adverse impact on plant safety. However, the Category 2 loose connections could have had an adverse affect on plant safety. The loose connections involve both the termination of incoming field cables as well as vendor terminations. Although some of this number could involve nonsafety-related circuits fed from the safety-related board/panel, a significant portion of the loose connections have been confirmed to be associated with saety-related circuits in various safety-related systems (e.g. Component Cooling System, Safety Injection System, Ventilating System, Essential Raw Cooling Water System, Residual Heat Removal System, etc.) and involve redundant divisions of safety-related circuits. During a seismic event, the loose connections must be assumed to create an open circuit. The resulting condition may place the plant in an indeterminate condition. Reference: WBFIR 930012 307 CDR 50-390, 391/95-05
Page Last Reviewed/Updated Wednesday, March 24, 2021
Page Last Reviewed/Updated Wednesday, March 24, 2021