05000280/FIN-2008006-01
From kanterella
Jump to navigation
Jump to search
Finding | |
|---|---|
| Title | Failure to Evaluate and Use Limiting Case 4160 VAC Bus Frequency and Voltage in Design Calculations (Section 1R21.2.12) |
| Description | The inspectors identified two examples of a Green non-cited violation of 10 CFR 50, Appendix B, Criterion III, Design Control, for failure to evaluate variations of emergency diesel generator (EDG) output frequency in electrical design loading calculations, and failure to consider worst case 4160 VAC bus voltage in safety related motor starting calculations. This finding was entered into the licensees corrective action program as condition reports (CR) 091493 and 091494. Planned corrective actions included revision of the EDG loading calculations to incorporate the most limiting voltages and frequencies. This finding is more than minor because it affects the Mitigating Systems Cornerstone objective ensuring the availability, reliability, and operability of the EDGs to perform the intended safety function during a design basis event and the cornerstone attribute of Design Control, i.e. initial design. The inspectors assessed the finding using the SDP and determined that the finding was of very low safety significance (Green) because the deficiencies did not result in any EDG being inoperable based upon additional analysis that showed that the EDGs had sufficient margin to accommodate the increased loading due to worst case acceptably high EDG output frequency; and all safety related motor loads remained operable since they were still capable of starting with the revised worst case low voltage values. (Section 1R21.2.12 |
| Site: | Surry  |
|---|---|
| Report | IR 05000280/2008006 Section 1R21 |
| Date counted | Mar 31, 2008 (2008Q1) |
| Type: | NCV: Green |
| cornerstone | Mitigating Systems |
| Identified by: | NRC identified |
| Inspection Procedure: | IP 71111.21 |
| Inspectors (proximate) | C Baron G Skinner S Rose W Fowler R Berryman J Hamman G Gardner B Desai B Collins |
| INPO aspect | |
| ' | |
Finding - Surry - IR 05000280/2008006 | |||||||||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Finding List (Surry) @ 2008Q1
Self-Identified List (Surry)
| |||||||||||||||||||||||||||||||||||||||||||||