ENS 57313

v t e ENS Event
12:40 Aug 3, 2024
Title	60-DAY Notification of Invalid Specified System Actuation
Event Description	The following information was provided by the licensee via phone and email: This 60-day telephone notification is being submitted in accordance with 10 CFR 50.73(a)(1) and 50.73(a)(2)(iv)(A). The event was an invalid actuation of the Unit 1 containment ventilation isolation (CVI) system. On August 3, 2024, at 0840 EDT, with Unit 1 at 100 percent power, train 'A' of the CVI system actuated due to an invalid signal from 1-RM-90-130, containment purge air exhaust monitor. 1-RM-90-130 was out of service for maintenance testing at the time of the invalid signal. The cause of the signal was determined to be the result of an installed multimeter timing out, creating a short in the actuation circuitry. The train 'A' CVI signal was a full actuation of that train and the system functioned as designed. Prior to and following the CVI alarm, all other radiation monitors were stable at their normal values; therefore, the CVI [actuation] was invalid. Control room operators performed appropriate checks and confirmed that all required automatic actuations occurred as designed. Subsequent completion of the maintenance instruction was successful. This event was entered into the corrective action program as CR 1948103. The NRC Resident Inspector was notified.

ENS 57313 +/-
Where
Sequoyah Tennessee (NRC Region 2)
Reporting

10 CFR 50.73(a)(1), Submit an LER, Invalid Actuation
Time - Person (Reporting Time:+907.8 h37.825 days <br />5.404 weeks <br />1.244 months <br />)
Opened:	Travis Holcomb 08:28 Sep 10, 2024
NRC Officer:	Robert A. Thompson
Last Updated:	Sep 10, 2024
57313 - NRC Website Loading map...
v • d • e

v t e Emergency Notification System
Sequoyah with 10 CFR 50.73(a)(1), Submit an LER
WEEKMONTHYEAR2024-08-03T12:40:00 [Table view]
[ENS list for Sequoyah]

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