05000373/LER-1983-015, Forwards LER 83-015/03L-0.Detailed Event Analysis Encl

Forwards LER 83-015/03L-0.Detailed Event Analysis Encl

ML20072F778
Person / Time
Site:	LaSalle
Issue date:	03/17/1983
From:	Diederich G COMMONWEALTH EDISON CO.
To:	James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
Shared Package
ML20072F782	List: 05000373/LER-1983-015, Forwards LER 83-015/03L-0.Detailed Event Analysis Encl 05000373/LER-1983-015-03, /03L-0:on 830217,while Testing Diesel Generator 1B Per LOS-DG-M3,diesel Tripped While Being Off Loaded.Diesel Restarted & Speed Varied Between 400 & 900 Rpm.Caused by Bad Connection at Run Solenoid.Connection Reconnected
References
830312, NUDOCS 8303240421
Download: ML20072F778 (2)

LER-1983-015, Forwards LER 83-015/03L-0.Detailed Event Analysis Encl

Event date:
Report date:
3731983015R00 - NRC Website

text

s

'N Commonwealth Edison c

J LaS;lle County Nuclezr Station V

Rural Routs #1, Box 220 z,

Marseilles, Illinois 61341 Telephone 815/357-6761 March 17, 1983 James G. Keppler Regional Administrator Region ill U.S. Nuclear Regulatory Commission 799 Roosevelt Road Glen Ellyn, IL 60137

Dear Sir:

Reportable Occurrence Report #83-015/03L-0 Docket #050-373 is being sub-mitted to your office in accordance with LaSalle County Nuclear Power Station Technical Specification 6.6.B.2 (b), conditions leading to opera-tion in a degraded mode permitted by a limiting condition for operation or plant shutdown required by a limiting condition for operation.

G J. Diederich Superintendent LaSalle County Station GJD/GW/rg Enclosure cc:

Director of Inspection & Enforcement Director of Management information & Program Control U.S. NRC Document Management Branch Inpo-Records Center File /NRC l

l l

MAR 21 y y 4

8303240421 830317 4,

PDR ADOCK 05000373 i

S PDR

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1.

LEf. NUMBER: 83-015/03L-0 II:

LASALLE COUNTY STATION: Unit I til.

DOCKET NUMBER:

050-373 IV.

EVENT DESCRIPTION

On2-17-83,whiketestingthe"1B'HPCSdieselgeneratorperLOS-DG-M3,the diesel tripped while it was being off-loaded.

The diesel was restarted and the diesel speed varied between 400 and 900 RPM. Work requrest L22579 was then initiated to investigate and resolve the problem.

V.

PROBABLE CONSEQUENCES OF THE EVENT:

The plant was shutdown at the time of the occurrence, and HPCS was not re-quired to be operable.

Therefore, safe plant operation was not affected.

However, this event was determined to be a failure, as defined in Regula-tory Guide 1.108, Revision 1, August 1977 This is because the diesel would not have come up and maintained the required speed to satisfactorily carry emergency loads.

VI.

CAUSE

The cause for the fluctuating speed was a bad connection at Ehe "Run" solenoid.

The solenoid is normally energized during diesel operation.

^ '"~

When the solenoid is de-energized, the governor shuts off ' fuel supply to the diesel, thus shutting it down.

The bad connection at the solenoid al-lowed it to de-ene'rgize every few seconds.

Thus, the diesel speed varied from 900 RPM (normal) to approxjmately 400 RPM (the ' speed to which it would decrease to before the solenoid would re-energize).

Vll. CORRECTIVE ACTION:

The solenoid was reconnected under Work Request L22579 The diesel monthly surveillance, LOS-DG-M3, was performed on the diesel on 2-18-83 to prove operability.

The other diesels will have their solenoid connections checked' to prevent a recurrence of the event.

A.I.R. 1-83-76 has been initiated to provide for a periodic check of all the diesels as part of LES-DG-101.

Prepared by:

J. J. Hietala 9"

P i

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