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

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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:

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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