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:
areas, cable spreading rooms, control rooms, and other congested areas; sharing raceways with nonsafety-related cables or with cables of the same system or other systems; prohibiting cable splices in raceways; spacing power and control wiring and components associated with safety-related electric systems in control boards, panels, and relay racks; and fire barriers and separation between redundant raceways. 3. Power Supplies and Distribution Systems. To 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, 8.3.2-15 Revision 3 - March 2007 design criteria, analyses, description, and implementation (as depicted on electrical drawings and performance characteristic curves). As endorsed by Regulatory Guide 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 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 Regulatory Guide 1.129. Regulatory Guide 1.128 and IEEE Std. 484 provide the basis for the review of design practices and procedures for storage,