ENS 48055: Difference between revisions
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StriderTol (talk | contribs) (Created page by program invented by Mark Hawes) |
StriderTol (talk | contribs) (Created page by program invented by StriderTol) |
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| event date = 06/28/2012 13:53 EDT | | event date = 06/28/2012 13:53 EDT | ||
| last update date = 06/28/2012 | | last update date = 06/28/2012 | ||
| title = Loss | | title = Loss of One of Two Offsite Power Sources | ||
| event text = At 1353 EDT on 06/28/2012, Susquehanna Steam Electric Station experienced a loss of power from one of two offsite power sources when transformer 20 shutdown automatically. All ESS [Engineered Safeguards System] electrical busses fed by this transformer automatically transferred to the other offsite power source (transformer 10). Additionally, startup bus 20, which is normally fed from transformer 20, automatically transferred to transformer 10. | | event text = At 1353 EDT on 06/28/2012, Susquehanna Steam Electric Station experienced a loss of power from one of two offsite power sources when transformer 20 shutdown automatically. All ESS [Engineered Safeguards System] electrical busses fed by this transformer automatically transferred to the other offsite power source (transformer 10). Additionally, startup bus 20, which is normally fed from transformer 20, automatically transferred to transformer 10. | ||
On each unit, multiple system containment isolation valves closed as a result of the electrical transient. Operators were able to reset and restore each system. On unit one, residual heat removal (RHR) shutdown cooling ceased operation during the transient. Shutdown cooling was restored within one hour by control room operators in accordance with off-normal procedures. Unit two remained at 100% power throughout the event. | On each unit, multiple system containment isolation valves closed as a result of the electrical transient. Operators were able to reset and restore each system. On unit one, residual heat removal (RHR) shutdown cooling ceased operation during the transient. Shutdown cooling was restored within one hour by control room operators in accordance with off-normal procedures. Unit two remained at 100% power throughout the event. |
Latest revision as of 22:03, 1 March 2018
Where | |
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Susquehanna Pennsylvania (NRC Region 1) | |
Reporting | |
10 CFR 50.72(b)(3)(iv)(A), System Actuation | |
LER: | 05000387/LER-2012-008 |
Time - Person (Reporting Time:+2.85 h0.119 days <br />0.017 weeks <br />0.0039 months <br />) | |
Opened: | Darvin Duttry 20:44 Jun 28, 2012 |
NRC Officer: | Joe O'Hara |
Last Updated: | Jun 28, 2012 |
48055 - NRC Website
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