05000311/LER-1983-001, Forwards LER 83-001/03L-0.Detailed Event Analysis Encl

Forwards LER 83-001/03L-0.Detailed Event Analysis Encl

ML20064M222
Person / Time
Site:	Salem
Issue date:	01/27/1983
From:	Midura H Public Service Enterprise Group
To:	Haynes R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML20064M224	List: 05000311/LER-1983-001, Forwards LER 83-001/03L-0.Detailed Event Analysis Encl
References
NUDOCS 8302150501
Download: ML20064M222 (3)

LER-2083-001, Forwards LER 83-001/03L-0.Detailed Event Analysis Encl

Event date:
Report date:
3112083001R00 - NRC Website

text

O PSEG Public Serv;ce Electric and Gas Company P.O. Box E Hancocks Bridge, New Jersey 08038 Salem Generating Station January 27, 1983 Mr. R. C. Haynes Regional Administrator USNRC Region 1 631 Park Avenue King of Prussia, Pennsylvania 19406

Dear Mr. Haynes:

LICENSE NO. DPR-75 DOCKET NO. 50-311 REPORTABLE OCCURRENCE 83-001/03L Pursuant to the requirements of Salem Generating Station Unit No. 2, Technical Specifications, Section 6.9,1.9.b, we are submitting Licensee Event Report for Reportable Occurrence 83-001/03L. This report is required within thirty (30) days of the occurrence.

Sincerely yours,

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H. J. Midura General Manager -

Salem Operations RF:ks pj CC: Distribution i

8302150501 830127 PDR ADOCK 05000311 S PDR The Energy People **

E2189 L'OM) 1181 L

Report. Number: 83-001/03L Report Date: 01-27-83 Occurrence Date: 01-06-83 Facility: Salem Generating Station Unit 2 Public Service Electric & Gas Company Hancock's Bridge, New Jersey 08038 IDENTIFICATION OF_ OCCURRENCE:

Reactor Trip System - Reactor Trip Breaker A - Inoperable.

This report was initiated by Incident Report 83-009.

CONDITIONS PRIOR TO OCGRRENG:

Mode 1 - RX Power 46 % - Unit Load 410 MWe.

DESCRIPTION OF OCCURRENCE:

At 1953 hours0.0226 days <br />0.543 hours <br />0.00323 weeks <br />7.431165e-4 months <br />, January 6, 1983, during routine operation, a reactor trip occurred due to a low level in No. 21 Steam Generator. Following the trip, the Control Room Operator noticed that Reactor Trip Breaker A had failed to open on the trip signal. Breaker B had opened and de-energized the rod drive mechanisms resulting in the shutdown.

Since Breaker A was inoperable, Limiting Condition for Operation 3.3.1 Acticn 1 applied.

With the reactor in a safe condition, the breaker was left in the closed position pending investigation of the problem. At 2018 hours0.0234 days <br />0.561 hours <br />0.00334 weeks <br />7.67849e-4 months <br />, the operator observed that Breaker A had tripped with no operator action.

AEEARENT CAUSE OF OCCURRENCE:

Investigation of the problem revealed that the trip breaker under voltage relay had malfunctioned. The problem apparently involved dirt or corrosion interfering with proper relay operation. Since the breaker is not frequently operated, insufficient self-cleaning of the relay mechanism occurred. Materials evidently accumulated and caused mechanical binding of the mechanism. A similar problem had been noted on August 20, 1982, and was documented in LER 82-072/03X-1.

ANALYSIS OF OCCURRENCE:

The operability of the Reactor Trip and Engineered Safety Feature Actuation Systems is required to provide the overall reliability, redundance, and diversity assumed available in the facility design for the protection and mitigation of accident and transient conditions.

The integrated operation of these systems is consistent with the assumptions of the accident analyses.

\

LER 83-001/03L ANALYSIS OF OCC11ERERCE: (cont'd)

Limiting Condition for Operation 3.3.1 Action 1 requires:

With the number of channels operable one less than required by the minimum channels operable requirement, be in hot standby within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />; however, one channel may be bypassed for up to 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> for surveillance testing per Specification 4.3.1.1 provided the other channel is operable.

Since the redundant trip breaker opened and the trip actually occurred, the incident did not involve any risk to the health and safety of the public. Due to the loss of redundancy, the event constituted operation in a degraded mode permitted by a limiting condition for operation. It is therefore reportable in accordance with Technical Specification 6.9.1.9b.

CORRECTIVE ACTION:

As a result of the trip, the unit entered Mode 3, and the limiting condition for operation no longer applied. The malfunctioning breaker was replaced with a spare from Salem Unit 1, and the new breaker was satisfactorily tested. The Reactor Trip System was returned to an operable status and a reactor startup completed at 0531 hours0.00615 days <br />0.148 hours <br />8.779762e-4 weeks <br />2.020455e-4 months <br />, January 7, 1983.

The breaker vendor was contacted concerning the problem; upon his recommendation the failed relay was cleaned, lubricated and readjusted. The breaker tested satisfactorily and was installed in Salem Unit 1 Reactor Trip System. To prevent future occurrences of this type, the breakers will be inspected during each refueling outage. The other Unit 1 breakers have been completed; Unit 2 breakers are scheduled for inspection during the present refueling.

EAILURE DATA:

Westinghouse Electric Corp.

l Circuit Breaker l Model DB-50 Type A 1

l l

Prepared By R. Frahm denfral Manager -

Salem Operations SORC Meeting No. 83-09 f

l

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