Document: NUREG-0800
Document ID: f9d2d9cb-1d13-407e-ad7a-523fff64de06
Document Type: srp
Title: DC POWER SYSTEMS (ONSITE)
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1007/ML100740391.pdf
Revision Date: 2023-06
Chapter: 8
Section ID: 8.3.2
CFR Part: 
CFR Title: 

Content:
ensure that the requirements of GDC 17 have been met regarding the dc power system having sufficient capacity and capability to supply the required distribution system loads, the staff will review the design bases, design criteria, analyses, description, and implementation (as depicted on electrical drawings and performance characteristic curves). As endorsed by RG 1.32, IEEE Std. 308 describes a method acceptable to the NRC staff for complying with the NRC=s regulations for the design, operation, and testing of dc power systems in nuclear power plants. To establish that the capacity of the dc supply is adequate to power the prescribed loads, reviewer checks the nameplate capacity claimed in the design bases against the 8.3.2-15 Revision 4 - May 2010 loads identified in electrical distribution diagrams. The staff will review the capability of the system by evaluating the performance characteristic curves that illustrate the response of the supplies to the most severe loading conditions at the plant. The performance characteristic curves would include voltage profile curves, discharge rate curves, and temperature effect curves. IEEE Std. 485 provides a method acceptable to the staff for sizing stationary lead acid batteries. The capacity of the dc supplies should be ensured by periodic discharge tests of the batteries, as described in IEEE Std. 450 and RG 1.129. RG 1.128 and IEEE Std. 484 provide the basis for the review of design practices and procedures for storage, location, mounting, ventilation, instrumentation, preassembly, assembly, and charging of large lead storage batteries. In coordination with other branches, the reviewer becomes familiar with the purpose and operation of each safety system, including system component arrangements as depicted on functional P&IDs, expected system performance as established in the accident and/or other relevant analyses (e.g., for SBO), modes of system operation and interactions during normal and accident conditions, and