Plants run well, staff is sharp
How about that fuse wiring....?
Power Reactor Event Number: 46182
Facility: SAN ONOFRE
Region: 4 State: CA
Unit: [ ] [2] [ ]
RX Type: [1] W-3-LP,[2] CE,[3] CE
NRC Notified By: LEON RAFNER
HQ OPS Officer: JOE O'HARA Notification Date: 08/17/2010
Notification Time: 13:56 [ET]
Event Date: 08/17/2010
Event Time: 03:00 [PDT]
Last Update Date: 08/17/2010
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(3)(ii)(B) - UNANALYZED CONDITION
Person (Organization):
GEOFFREY MILLER (R4DO)
Unit SCRAM Code RX CRIT Initial PWR Initial RX Mode Current PWR Current RX Mode
2 N Y 100 Power Operation 100 Power Operation
Event Text
UNANALYZED CONDITION DUE TO POTENTIAL WIRING DISCREPANCY
"On August 16, 2010, at about 0100 PDT, SONGS Unit 2 Train 'A' Emergency Diesel Generator (EDG) 2G002 was removed from service for planned maintenance. Train 'A' EDG is the Appendix R protected Train.
"At about 1545 the same day, Southern California Edison (SCE) discovered a potential wiring discrepancy in the electronic governor. At 0300 on August 17, 2010, SCE determined two wires on a fire isolation fuse were confirmed to be terminated differently than specified in plant drawings and that the discrepancy would prevent the fuse and associated fire isolation switch from performing its Appendix R fire isolation function for the Train 'A' EDG. In accordance with NUREG-1022, Rev. 2, SCE is reporting this occurrence in accordance 10CFR50.72(b)(3)(ii)(B).
"While the incorrect wiring impacted the Appendix R qualifications of the Train 'A' EDG, it did not impact its other design functions and the EDG was capable to fulfill its safety function for all other Design Basis Events. Therefore, SCE considers the safety significance of the condition to be minimal.
"In accordance with LCS specification 3.7.113.1 Condition A, SCE will implement hourly Fire Watches for the impacted plant areas until such time that the wiring on the Unit 3 Train 'A' Emergency Diesel Generator 3G002 is conformed to be correct or has taken actions to correct any wiring discrepancy. An evaluation will be conducted to determine the cause of this condition.
"At the time of this occurrence, Unit 2 and Unit 3 were both at 100% power."
"The NRC Resident Inspector will be notified of this occurrence and will be provided with a copy of this report."