Document: NUREG-0800
Document ID: 9fa7092c-7628-402d-9028-6601d5f5fdfb
Document Type: srp
Title: DC POWER SYSTEMS (ONSITE)
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0705/ML070550063.pdf
Revision Date: 2023-06
Chapter: 8
Section ID: 8.3.2
CFR Part: 
CFR Title: 

Content:
REVIEW RESPONSIBILITIES Primary - Organization responsible for the review of onsite dc power systems Secondary - None I. AREAS OF REVIEW The review addresses the descriptive information, analyses, and referenced documents, including electrical single-line diagrams, electrical control and schematic, functional piping and instrumentation diagrams (P&IDs), logic diagrams, tables, and physical arrangement drawings for the direct current (dc) onsite power system presented in the applicant’s safety analysis report (SAR). The intent of the review is to determine whether the dc onsite power system satisfies the requirements of General Design Criteria (GDCs) 2, 4, 5, 17, 18, and 50 and will perform its intended functions during all plant operating, accident, and station blackout (SBO) conditions. The dc power systems include those dc power sources and their distribution systems and vital supporting systems that are provided to supply motive or control power to safety-related equipment and to equipment used to respond to an SBO event. Batteries and battery chargers serve as the power sources for the dc power system, and inverters convert dc from the dc distribution system to alternating current (ac) instrumentation and control power, as required. 8.3.2-2 Revision 3 - March 2007 These three components, when combined, provide an uninterruptible power system (UPS) that furnishes a continuous, highly reliable source of ac supply. The specific areas of review are as follows: 1. System Redundancy Requirements. The staff will review the onsite dc power system to determine whether the required redundancy of components and subsystems is provided such that the system safety function can be accomplished, assuming a single failure. This requires an examination of the dc power system configuration regarding both power sources and their associated distribution systems, including the batteries, battery chargers, power supply feeders, panel arrangements, loads supplied from each battery,