Document: NUREG-0800
Document ID: a2680f96-0e15-402d-89ab-688ff09806a8
Document Type: srp
Title: with respect to the specified station blackout event/duration.13
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070497.pdf
Revision Date: 2023-06
Chapter: 8
Section ID: 8.3.2
CFR Part: 
CFR Title: 

Content:
on system. At least one circuit will be available within a few seconds following a loss of coolant accident and is considered an immediate access circuit. Each circuit is designed and located so as to minimize to extent practical the likelihood of their simultaneous failure under operating and postulated accident and environmental conditions. Each circuit has been sized with sufficient capacity to supply all connected loads. Each circuit can be made available to the onsite power system, assuming loss of the onsite ac standby power supplies and loss of the other offsite circuit, to assure ensure that fuel design limits and design conditions of the reactor coolant pressure boundary are not exceeded. The switchyard is arranged such that each offsite circuit can be isolated from other circuits to permit reestablishment of offsite power to the onsite distribution system. The switchyard is also arranged such that single events (e.g., a spurious relay trip or a breaker not operating during fault conditions) will not cause simultaneous failure of all offsite circuits to the switchyard. The results of the applicant's grid stability analysis indicated that loss of the largest generating capacity being supplied to the grid, loss of largest load from the grid, loss of the most critical transmission line, or loss of the unit itself will not cause grid instability. This meets the guidelines of Regulatory Guide 1.32, "Criteria for Safety-Related Electric Power Systems for Nuclear Power Plants." 3. The applicant has met the requirements of GDC 18, "Inspection and Testing of Electric Power Systems," with respect to the capability to test systems and associated components during normal plant operation and the capability to test 88 the transfer of power from the nuclear power unit, the offsite preferred power system, and the onsite power system. 4. The applicant’s overall compliance with the requirements of 10 CFR 50.63 is discussed in Section 8.4 of the safety evaluation report