The team identified four examples of a Green non-cited violation of title 10 Code of Federal Regulations Part 50, Appendix B, Criterion III, Design Control. Specifically, Catawba failed to verify the electrical design of safety-related switch gear for the
emergency core cooling system equipment and distribution systems (4160 volts-alternating-current (VAC), 600 VAC, and 125 volt-direct- current (VDC)): 1) Some circuit breakers had inadequate voltages that did not meet the minimum qualified requirements (90 VDC), 2) The design was not evaluated for the effects of electrical
transients on control voltages that could affect the assumptions in the plant safety analyses for sequencing of loads and potentially affect the control fuses, 3) The effects of degraded voltages was not correlated to the component protection devices to prevent damage or unavailability of equipment during an event, and 4) Motor control centers and components located in the diesel control area were not qualified to perform their safety function during expected environmental
transients.
