ENS 52803

v t e ENS Event
15:20 Apr 17, 2017
Title	60-Day Optional Telephonic Notification of Invalid Specified System Actuation
Event Description	On April 17, 2017 at 1120 EDT, following scheduled maintenance, the Reactor Protection System (RPS) 'A' bus was returned to its normal supply, the RPS 'A' motor generator (MG) set. The RPS MG set had been running loaded for 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> when the RPS 'A' bus tripped. Maintenance personnel had connected probes of a grounded oscilloscope to check for proper operation of the MG set, resulting in the RPS 'A' bus trip. The controlling procedure did not contain a caution about using only an ungrounded oscilloscope. The trip of the RPS 'A' MG set resulted in a half scram and an invalid isolation signal causing primary containment isolation valves in multiple systems to isolate. This event is reportable per 10 CFR 50.73 (a)(2)(iv)(A) since the containment isolation was not part of a pre-planned sequence and the event resulted in the invalid actuation of general containment isolation valves in more than one system. Corrective actions include revising the governing procedure with the proper precaution and limitation to require the use of an ungrounded oscilloscope. A training needs analysis will also be performed to cover the lessons learned from this event. The licensee notified the NRC Resident Inspector.

ENS 52803 +/-
Where
Hatch Georgia (NRC Region 2)
Reporting

10 CFR 50.73(a)(1), Submit an LER, Invalid Actuation
Time - Person (Reporting Time:+1385.37 h57.724 days <br />8.246 weeks <br />1.898 months <br />)
Opened:	Rodger Lower 08:42 Jun 14, 2017
NRC Officer:	Howie Crouch
Last Updated:	Jun 14, 2017
52803 - NRC Website
v • d • e

v t e Emergency Notification System
Hatch with 10 CFR 50.73(a)(1), Submit an LER
WEEKMONTHYEAR2023-11-02T01:11:00 [Table view]
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