05000395/LER-1982-058, Forwards LER 82-058/03L-0.Detailed Event Analysis Encl

Forwards LER 82-058/03L-0.Detailed Event Analysis Encl

ML20028E069
Person / Time
Site:	Summer
Issue date:	01/13/1983
From:	Dixon O SOUTH CAROLINA ELECTRIC & GAS CO.
To:	James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
Shared Package
ML20028E070	List: 05000395/LER-1982-058, Forwards LER 82-058/03L-0.Detailed Event Analysis Encl 05000395/LER-1982-058-03, /03L-0:on 821214,urgent Failure Alarm Due to Loss of Power Occurred During Restoration of Rod Control Sys Upon Completion of Power Operational Testing.Caused by Oxidation Between Fuse & Fuse Block Mating Surfaces
References
NUDOCS 8301200322
Download: ML20028E069 (3)

LER-1982-058, Forwards LER 82-058/03L-0.Detailed Event Analysis Encl

Event date:
Report date:
3951982058R00 - NRC Website

text

v)

SOUTH CAROLINA ELECTRIC & GAS COMPANY 1

post orriCE 7e4 COLuus A. SOUTH CAROUNA 29218 O. W. DixoN. JR.

January 13, 1983 y,

WCE PREWDENT NUCLEAR OPERATIONS r0 Mr. James P.

O'Reilly, Director U.S. Nuclear Regulatory Commission Region II, Suite 3100 101 Marietta Street, N.W.

Atlanta, Georgia 30303

SUBJECT:

Virgil C. Summer Nuclear Station.

Docket No. 50/395 Operating License No. NPF-12 Thirty Day Written Report LER 82-058

Dear Mr. O'Reilly:

Please find attached Licensee Event Report #82-058 for Virgil C. Summer Nuclear Station.

This Thirty Day Report is required by Technical Specification 6.9.1.13.(b) as a result of entry into Action Statement (b) of Technical Specification 3.1.3.1,

" Reactivity Control Systems," on December 14, 1982.

Should there be any questions, please call us at your convenience.

Very truly yours,

[

9

(

O. W.

Dixon, Jr.

CJM:OWD:dwf Attachment cc:

V. C.

Summer A.

R.

Koon T.

C. Nichols, Jr.

G.

D.

Moffatt E.

C.

Roberts Site QA O. W. Dixon, Jr.

C.

L. Ligon (NSRC)

G.

J.

Braddick H.

N.

Cyrus H.

T. Babb J.

L.

Skolds D. A.

Nauman J.

B.

Knotts,'Jr.

M.

B. Whitaker, Jr.

B.

A. Bursey W.

A. Willians, Jr.

I&E (Washington)

Document Management Branch O.

S. Bradham INPO Records Center R.

B.

Clary NPCF M.

N. Browne File h

_ r.m\\1, Col 8301200322 830113 PDR ADOCK 05000395 [h

6

Mr. James P.

O'Reilly LER No.82-058 Page Two January 13, 1983 DETAILED DESCRIPTION OF EVENT On December 14, 1982, at 0840 hours0.00972 days <br />0.233 hours <br />0.00139 weeks <br />3.1962e-4 months <br /> with the Plant in Mode 1, Control Rod Drive Cabinet 2BD became inoperable.

An Urgent Failure Alarm was received during restoration of the Rod Control System on completion of Power Operation Test Procedure (POT-8),

" Static Rod Drop and Rod Below Bank Position Measurements."

The loss of this cabinet -- affecting 12 rods -- resulted in the inoperability of Group 2 Rods of Control Banks B, D, and Shutdown Bank B, which placed the Plant into Action Statement (b) of Technical Specification 3.1.3.1.

PROBABLE CONSEQUENCES There were no adverse consequences resulting from this event.

The Group 2 Rods were inoperable in the Manual arm Auto Control modes, but still retained the capability to trip during a plant emergency.

CAUSE(S) OF THE OCCURRENCE The occurrence was due to oxidation between the fuse and fuse block mating surfaces.

The oxidation on the metallic surfaces inhibited the circuit continuity for Phase A Stationary Gripper Voltage.

IMMEDIATE CORRECTIVE ACTIONS TAKEN Operations personnel had just completed the withdrawal of Rod D-10 in Bank B, Group 1, to 228 steps when they received the Urgent Failure Alarm at 1840 hours0.0213 days <br />0.511 hours <br />0.00304 weeks <br />7.0012e-4 months <br />.

Attempts to move the rods in Group 2, Control Banks B and D after receipt oi the alarm were unsuccessful at time of the event and at 1945 hours0.0225 days <br />0.54 hours <br />0.00322 weeks <br />7.400725e-4 months <br /> when Cabinet 2BD Alarm Reset was depressed.

Investigation into the cause of failure by Instrumentation personnel indicated that fuse FU-2 on Phase A Stationary Gripper Voltage had blown.

However, the fuse was found to be good upon removal from the fuse block.

Excessive oxidation observed on the metallic surface of the fuse had apparently been the reason for the 243 volt drop noted prior to fuse removal.

The Alarm Reset cleared the Urgent Failure Alarm after the fuse was cleaned and replaced in the fuse holder at 2031 hours0.0235 days <br />0.564 hours <br />0.00336 weeks <br />7.727955e-4 months <br />.

All rods were capable of normal movement at this time.

Mr. Jaues P.

O'Reilly LER No.82-058 Page Three January 13, 1983 ACTION TAKEN TO PREVENT RECURRENCE The Control Rod Drive Cabinet fuses are being added to the Station Preventive Maintenance Program to prevent recurrences of this nature.

The preventive maintenance procedure development is expected to be complete by March 1, 1983, and will be scheduled for performance during refueling outages.

P e