PNO-III-97-032, on 970410,licensee Shut Down Unit 2 After Declaring Merlin-Gerin 4 Kv Breakers Inoperable.Breaker Deficiencies Same Ones Prompting Quad Cities Unit 1 Shutdown on 970409.NRC Resident Inspectors Observed Reactor Shutdown
| ML17187A904 | |
| Person / Time | |
|---|---|
| Site: | Dresden, Quad Cities  |
| Issue date: | 04/11/1997 |
| From: | Kropp W, Lerch R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | |
| References | |
| PNO-III-97-032, PNO-III-97-32, NUDOCS 9704110164 | |
| Download: ML17187A904 (1) | |
April 11. 1997 PRELIMINARY NOTIFICATION OF E.ENT OR UNUSUAL OCCURRENCE PNO-III-97-032 This preliminary notification constitutes EARLY notice of events of POSSIBLE safety or public interest sig-ificance. The information is as initially received without verification or evaluation. and is basically all that is known by Region III staff (Li=le. Illinois) on this date.
Facility Commonwealth Edison Co.
Dresden 2 3 Morris.Illinois Dockets: 50-237.50-249 Liceflsee Emergency Classification Notification of Unusual Event Alert Site Area Emergency General Emergency X Not Applicable
Subject:
O~TAGE DUE TO INOPERABLE MERLIN-GERIN 3REAKERS On April 10, 1997. the licensee shut down Unit 2 after declaring all the*
Merlin-Gerin 4 kV breakers to be inoperable. The breaker deficiencies are the same ones that prompted the Quad Cities Unit 1 shutdown on April 9, 1997. See PNO-III-97-39031. The licensee shut do~n Dresden Unit 2 after inspecting busses 23 to 23-1 tie breaker and finding the auxiliary switchpack broken completely -=ree from its mounting plate. This breaker is required to open for an emffgency diesel gener*ator to properly pick-up the busse 23-1 loads.
The auxiliary switchpack was 01ly supported by i~s operating rod and the attached wires. Since October 1996 an action request had identified an improperly indicating local injicator on the breaker. Visual and boroscope inspections of some Jf the other similar breakers in the plant have only identified minor cr2:king. Technical Specifications required the plant shutdown as a result of the breaker deficiencies. Unit 3 is shutdown for a refueling outag=.
NRC resident inspectors obserr=d the reactor shutdown activities. The NRC vendor inspection branch is following-up on the breaker defi ci enci es.
The State of Illinois has beer notified. The information in this preliminary notification has t.~en reviewed with the* licensee management.
. The licensee notified the NRC Operations Center at 12:20 a.m. (EDT) on April 11. 1997. This information is current as o~ 10:30 a.m. on April 11.
1997.
Contact:
ROBERT LERCH (630)829-9759 9704110164 970411 PDR I~E R
PNO-III-97-032 PD WAYNE KROPP (630)829-9633