Document: NUREG-0800
Document ID: 757b676a-0f71-4094-8677-ca3a50743281
Document Type: srp
Title: Revision 7 – August 2016
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1601/ML16019A344.pdf
Revision Date: 2023-06
Chapter: 7
Section ID: 7
CFR Part: 
CFR Title: 

Content:
its operational states while the system is operating at the limits of its equipment qualification envelope. The logic and diagnostics should be representative of the logic used in actual operation to a degree that provides assurance that the system states produced by the actual system will be tested during the equipment qualification process. 3.10 Displays and Manual Controls Displays and manual controls provided for compliance with Point 4 of the NRC position on D3 should be sufficient both for monitoring the plant state and to enable control room operators to actuate systems that will place the plant in a safe shutdown condition. In addition, the displays and controls should be sufficient for the operator to monitor and control the following critical safety functions: reactivity level, core heat removal, reactor coolant inventory, containment isolation, and containment integrity. These displays and controls provide plant operators with information and control capabilities that are not subject to CCF due to errors in the plant automatic DI&C safety systems because the displays and controls are independent and diverse from the safety system. The point at which the manual controls are connected to safety equipment should be downstream of equipment that can be adversely affected by a CCF. These connections should not compromise the integrity of interconnecting cables and interfaces between local electrical or electronic cabinets and the plant’s electromechanical equipment. To achieve system-level actuation at the lowest possible level in the safety system architecture, the controls may be connected either to discrete hardwired components or to simple (e.g., component function can be completely demonstrated by test,) dedicated, and diverse, software-based digital equipment that performs the coordinated actuation logic. The displays may include digital components that are not adversely affected by a CCF of the safety functions credited in the accident analysis.