Document: NUREG-0800
Document ID: b6428ab0-2037-4bac-9b93-b46af9f2fdfb
Document Type: srp
Title: DATA COMMUNICATION SYSTEMS
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0706/ML070650036.pdf
Revision Date: 2023-06
Chapter: 7
Section ID: 7.9
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Content:
sis of the design’s meeting the specific requirements of IEEE Std. 279-1971 or IEEE Std. 603-1991. The DCS review should address the applicable topics identified in SRP Table 7-1. SRP Appendix 7.1-A describes review methods for each topic. Major design considerations that should be emphasized in the review of the interlock systems are identified below. • Quality of components and modules - See SRP Appendix 7.1-B, subsection 4.3, or SRP Appendix 7.1-C, subsection 5.3. • DCS software quality - See SRP BTP 7-14. • Performance - The review should verify that the protocol selected for the DCS meets the performance requirements of all supported systems. The real-time performance should be reviewed with SRP BTP 7-21. This should include verification that DCS safety system timing is deterministic or bounded. Time delays within the DCS and measurement inaccuracies introduced by the DCS should be considered when reviewing the instrumentation setpoints (refer to Regulatory Guide 1.105, Revision 3, “Setpoints for Safety-Related Instrumentation,” and SRP BTP 7-12). Data rates, data bandwidths, and data precision requirements for normal and off-normal operation, including the impact of environmental extremes, should be reviewed. There should be sufficient excess capacity margins to accommodate likely future increases in DCS demands or software or hardware changes to equipment attached to the DCS. The error performance should be specified. Vendor test data and in situ test results should be reviewed to verify the performance. Analytical justifications of DCS capacity should be reviewed for correctness. The interfaces with other DCSs or other parts of the I&C system should be reviewed to verify compatibility. • Reliability - The potential hazards to the DCS and from the DCS should be reviewed. Unneeded but included DCS functions should be reviewed to assure that they cannot be inadvertently activated and thereby prevent operation of the safety functions. The effects