Document: NUREG-0800
Document ID: b09bdecd-fb52-4a15-ab35-7b597cbbaa13
Document Type: srp
Title: Appendix 7-A
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0525/ML052500546.pdf
Revision Date: 2023-06
Chapter: 7
Section ID: 7
CFR Part: 
CFR Title: 

Content:
ion and response time tests for each sensor. To monitor systematic drift or degradation, at each refueling cycle a newly calibrated RTD or a new RTD with recent calibration data should be installed at representative location(s) determined by analysis. The cross-correlation to the reference RTD(s) should be monitored using "as found" and "as left" data records. Test data and analysis should identify and account for differences in isothermal conditions and demonstrate that the drift is random and is within an acceptable band as determined by setpoint analyses, and that systematic drift is not exhibited. If historical data reveals potential drift problems which would exceed the allowable values of temperature drift in testing for any sensor then the applicant/licensee should verify the calibration of the deviating sensor(s) and identify appropriate corrective action. Analysis to project RTD drift should be available for all RTDs within the protection system. Control/Protection Interaction and Common-Mode Failure During In-Situ Testing If the applicant/licensee uses test equipment common to redundant channels, qualified isolation should be provided to preclude single-failure effects on redundant channels or unacceptable protection/control interactions. 4. Review Procedures The protection system design basis should be examined to identify the requirements for RTD accuracy and time response. The cross-calibration method and calibration and response time data should be examined to identify calibration inaccuracies, uncertainties, and errors, and to confirm that the cross-calibration method is adequate. The programmatic documentation of the cross-calibration process should be reviewed with respect to the acceptance criteria above. This review should confirm that the calibration process is consistent with all setpoint analysis assumptions and design basis requirements. Rev. 4 — June 1997 Appendix 7-A BTP HICB-13-6 C. References ANSI/IEEE Std 279-1971. "Criteria for