ML12268A153

IR 1319908; B2F26 U2 Reactor Trip Due to Electrical Fault and Unusual Event

ML12268A153
Person / Time
Site:	Byron
Issue date:	01/30/2012
From:	Exelon Generation Co
To:	NRC/RGN-III
References
FOIA/PA-2012-0287
Download: ML12268A153 (2)

Text

,. .,. ,=0Go Back Print I New Search I Home AR 01319908 Report Aff Fac: Byron Aff Unit: 02 Aff System: SY AR Type: CR Owed To: ACAPALL Status: APPROVED Due Date: 02/29/2012 Event Date: Disc Date: 01/30/2012 01/30/2012 CR LevellClass:

How Discovered:

WR/PIMS AR: 2/A H01 Orig Date: 01/30/2012 Equip Tag: Action Request Details

Subject:

U2 REACTOR TRIP DUE TO ELECTRICAL FAULT AND UNUSUAL EVENT

Description:

(b)(6) (b)(6)Originator:

I Supv Contacted:

Condition

==

Description:==

At 1002 U2 reactor tripped due to an aparent electrical fault. A loss of offsIte power followed.

2A and 2B Diesel generators energized the ESF buses. U2 SAT was Isolated based on reports of smoke. Investigation shows a failure of C Phase at the SAT disconnect.

Immediate actions taken: Enteed 2BEP 0. The Main steam isolation valves were closed. Initiated actions per the BEPs.Recommended Actions: Perform a root cause. Subsequent IR's will be written for repairs.Operable Basis: Reportable Basis: Functionality Basis: (b)(6)SOC Reviewed by: 01/30/2012 16:28:00 CST SOC Comments: Send to Ops to generate root cause actions. Level 2 event due to plant trip per LS-AA-120.

ZINWR 1/30/12 Assignments Assign #: 01 Assigned Status: AWAIT/C To: M itn the Freedm ofd n md= d~~ the Freedom of lnb , C_2_

Aff Fac: Byron Prim Grp: ACAPALL Due Date: 02/04/2012 Assign Type: TRKG Sec Grp: Orig Due Date: Priority: Schedule Ref: Unit Condition:

Subject/Description:

U2 REACTOR TRIP DUE TO ELECTRICAL FAULT AND UNUSUAL EVENT