05000311/LER-1981-128, Forwards LER 81-128/03L-0.Detailed Event Analysis Encl

Forwards LER 81-128/03L-0.Detailed Event Analysis Encl

ML20040B392
Person / Time
Site:	Salem
Issue date:	01/13/1982
From:	Midura H Public Service Enterprise Group
To:	Haynes R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML20040B393	List: 05000311/LER-1981-128, Forwards LER 81-128/03L-0.Detailed Event Analysis Encl 05000311/LER-1981-128-03, /03L-0:on 811217,pressurizer Low Level Heaters Off Alarm Annunciated,Letdown Isolation Valves Closed & Pressurizer Pressure Fell Below Limit.Caused by Fuse Failure in Bistable Module.Fuse Replaced
References
NUDOCS 8201260005
Download: ML20040B392 (2)

LER-1981-128, Forwards LER 81-128/03L-0.Detailed Event Analysis Encl

Event date:
Report date:
3111981128R00 - NRC Website

text

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O PSIsG har. ',i w. Uca ric ano G.c. Cwr :e. <

P.O. Bo ifM Hanor) s Br :.", Neu Jerwy 08038 Salern Generating Station January 13, 1982 Mr.

R.

C.

Ilaynes Di. rector of USNRC Office of Inspection and Enforcement Region 1 631 Park Avenue King of Prucsia, Pennsylvania 19406

Dear Mr. Ilaynes:

LICENSE NO. DPR-75 DOCKET NO. 50-311 REPORTABLE OCCURRENCE 81-128/03L 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 81-128/03L.

This report is required within thirty (30) days of the occurrence.

Sincerely yours,

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II. 'J. Midura l

General Manager -

Salem Operations CC.

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Report Number:

81-128/03L Report Date:

1-13-82 l

Occurrence Date:

12-17-81 Facility:

Salem Generating Station, Unit 2 Public Service Electric & Gas Company Hancocks Bridge, New Jersey 08038 IDENTIFICATION OF OCCURRENCE:

Pressurizer Pressure - Below DNB Parameters.

This report was initiated by Incident Report 81-501.

t CONDITIONS PRIOR TO OCCURRENCE:

Mode 1 - Ex Power 954 - Unit Load 1040 MWe DESCRIPTION OF OCCURRENCE:

1 3

At 0511 hours0.00591 days <br />0.142 hours <br />8.449074e-4 weeks <br />1.944355e-4 months <br />, December 17, 1981, during normal power operations, the PRESSURIZER LOW LEVEL HEATERS OFF alarm annunciated and letdown i

isolation valves 2CV2, 2CV3, 2CV4, and 2CV5 went to the closed i

position, isolating letdown flow.

In addition, the pressurizer heaters tripped off.

Pressurizer level indication remained normal.

The condition could not be cleared by selecting the other control channel.

Pressurizer level increased and pressurizer pressure

'4 decreased.

At 0516 hours0.00597 days <br />0.143 hours <br />8.531746e-4 weeks <br />1.96338e-4 months <br /> the PRESSURIZER HIGH LEVEL HEATERS ON alarm annunciated, but the heaters did not actuate.

At 0528 hours0.00611 days <br />0.147 hours <br />8.730159e-4 weeks <br />2.00904e-4 months <br /> the REACTOR COOLANT LOW PRESSURE HEATERS ON alarm annunciated, but again the heaters did not actuate.

Excess letdown was established.

At 0533 hours0.00617 days <br />0.148 hours <br />8.812831e-4 weeks <br />2.028065e-4 months <br /> pressurizer pressure decreased below 2220 PSlA and Action Statement 3.2.5 was entered.

This occurrence constituted operation in a degraded inode in accor-dance with Technical Specification 6.9.1.9.b.

DESIGNATION OF APPARENT CAUSE OF OCCURRENCE:

4 i

The fuse in the 2LC-459C bistable module failed, resulting in letdown isolation and loss of the pressurizer heaters, due to an erroneous 1

low level signal.

The bistable failure precluded letdown isolation and pressurizer heater control except manually at the breaker panel.

Charging flow for pump seal injection caused pressurizer level to i

increase due to letdown isolation.

t

LER 81-128/03L ANALYSIS OF OCCURRENCE:

Technical Specification 3.2.5 requires:

With either the reactor coolant system T or pressurizer avStore the parameter pressure parameter exceeding its limit, re to within its limit within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> or reduce thermal power to less than 5% of rated thermal power within the next 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />.

CORRECTIVE ACTION

At 0539 hours0.00624 days <br />0.15 hours <br />8.912037e-4 weeks <br />2.050895e-4 months <br /> the fuse in the bistable module 2LC-459C was replaced, the PRESSURIZER LOW LEVEL HEATERS OFF alarm was cleared, and the pressurizer heaters actuated.

Normal letdown flow was restored, and at 0545 hours0.00631 days <br />0.151 hours <br />9.011243e-4 weeks <br />2.073725e-4 months <br /> pressurizer pressure increased above 2220 PSlA, and Action Statement 3.2.5 was terminated.

Subsequently, a letter was issued to all licensed operators detail-ing the event and explaining the consequences and appropriate actions.

FAILURE DATA:

Fuse 5 AMP 125 Volt M

Prepared By F.

Dickey

<, /. Nt. - Nr.

/

General Manager -

t Salem Operations SORC Meeting No.

82-07 l