Document: NUREG-0800
Document ID: b75d082b-2493-4543-981a-2ee136d737cf
Document Type: srp
Title: BTP 8-9-1
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1405/ML14057A433.pdf
Revision Date: 2023-06
Chapter: 8
Section ID: 8
CFR Part: 
CFR Title: 

Content:
s, surveillance requirements, trip setpoints, alarm set points, and maximum and minimum allowable values for the open phase conditions relays and associated time delay devices. 2. Nuclear Power Plants with Passive Safety Features New reactor licensees, COL applicants, and design centers for passive safety features plant designs under 10 CFR Part 52 should address the following design criteria: I. Detection and Alarms If the open phase condition prevents important-to-safety functions: An open phase condition should be automatically detected and alarmed in the control room unless it can be shown that the open phase condition does not prevent functioning of important-to-safety SSCs. Detection circuits for the open phase condition, which prevents the functioning of important-to-safety SSCs, should be sensitive enough to identify an open phase condition under all operating electrical system configurations and loading conditions for which they are required to be operable. II. Actuation circuits If open phase condition actuation circuits are required, the design should minimize misoperation, maloperation, and spurious actuation by providing independent dual sensors and actuation logics that could cause separation from an operable off-site power source. Additionally, the protective scheme should not separate the operable off-site offsite source in the range of voltage unbalance normally expected in the transmission system. Licensees/applicants should perform failure modes analysis to demonstrate that the additional actuation circuit design does not result in lower overall plan operation reliability. These devices should be coordinated with other protective devices in both the transmission system and the plant’s electrical system (e.g., fault protection, overcurrent, etc.). III. Restoration of preferred or Onsite AC Power Following detection of an open phase condition and alarm in the control room, plant procedures should specify operator actions to ensure the standby