Document: NUREG-0800
Document ID: b351c30f-74b4-4d36-833e-939d23abae4e
Document Type: srp
Title: D-C POWER-SYSTEMS (ONSITE)
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0523/ML052350494.pdf
Revision Date: 2023-06
Chapter: 8
Section ID: 8.3.2
CFR Part: 
CFR Title: 

Content:
t d-c to a-c for instrumentation and control power are reviewed to assure that they have sufficient capacity and capability to perform their intended functions. This will require an examination of the characteristics and design requirements of each load; the length of time each load is required; the combined load demand connected to each battery or battery charger during the "worst" operating condition; the voltage recovering character- istics of the battery and battery chargers; and the continuous and short-term ratings for the battery and battery chargers. In addition, where the proposed design provides for the connection of nonsafety-related loads to the d-c power system and sharing of batteries and battery chargers between units at the same site, particular review emphasis is given to assuring against marginal capacity and degradation of reliability that may result from implementing such design provisions. 4. Idehtification The means proposed for identifying the d-c power system components -including cables and cable trays as safety-related equipment in the plant are reviewed. Also, the identification scheme used to distinguish between redundant cables and raceways of the power system is reviewed. S. Vital Supporting Systems The instrumentation, control circuits, and power connections of vital supporting systems are reviewed to determine that they are designed to the same criteria as those for the Class lE loads and power systems that they support. This will include an examination of the vital supporting system component redundancy, power feed assignment to instrumentation, control of loads, initiating circuits, load characteristics, equipment identification scheme, and design criteria and bases for the installation of redundant cables. 6. Surveillance and Testing The.means proposed for monitoring the status of system operability are reviewed. Periodic onsite testing capability is reviewed. 7. Other Review Areas The d-c system is reviewed to determine that: (a)