ML19283A390

Forwards LER 80-041/03L-0

ML19283A390
Person / Time
Site:	Fort Saint Vrain
Issue date:	08/22/1980
From:	Warembourg D PUBLIC SERVICE CO. OF COLORADO
To:	Seyfrit K NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
Shared Package
ML19283A392	List: ML19283A390 ML19283A393
References
P-80278, NUDOCS 8008260466
Download: ML19283A390 (6)

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~D pubne service company oe concerdo

( 16805 ROAD 19%

C- J PLATTEVILLE, COLORADO 80651 August 22, 1980 Fort St. Vrain Unit No. 1 P-80278 Mr. Karl V. Seyfrit, Director Nuclear Regulatory Comission Region IV Office of Inspection and Enforcement 611 R;ran Plaza Drive Suite 1000 Arlington, Texas 76012

Reference:

Facility Operating License No. DPR-34 Docket No. 50-267

Dear Mr. Seyfrit:

Enclosed please find a copy of Reportable Occurrence Report No. 50-267/

80-41, Preliminary, submitted per the requirements of Technical Specif1-cation AC 7.5.2(b)1 and AC 7.5.2(b)2.

Also, please find enclosed one copy of the Licensee Event Report for Reportable Occurrence Report No. 50-267/80-41.

Very truly yours,

/

Don Wa embourg /

Manager, Nuclear Production DW/cis Enclosure cc: Director, MIPC 003

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8008260466

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REPORT DATE: August 22, 1980 REPORTABLE OCCURRENCE 80-41 ISSUE O OCCURRENCE DAIE: July 24, 1980 Page 1 of 5 FORT ST. VRAIN NUCLEAR GENERATING STATION PUBLIC SERVICE CCMPANY OF COLORADO 16805 WELD COUNTY ROAD 191/2 PLATTEVILLE, COLORADO 80651 REPORT NO. 50-267/80-41/03-L-0 Preliminary IDENTIFICATION OR OCCURRENCE:

During the July performance of the monthly check of the helium circulator seal malfunction pressure differential switches, it was discovered that one of twelve switch units tripped outside the limits specified in LCO 4.4.1, Table 4.4-3.

During the August performance of the monthly check of the helium circulator seal manfunction pressure differential switches, it was discovered that four of the twelve switch units tripped outside the limits specified in LCO 4.4.1, Table 4.4-3.

These are reportable per Fort St. Vrain Technical Specification AC 7.5.2(b)1 and AC 7.5.2(b)2.

EVENT DESCRIPTION:

During normal plant operation, instrument personnel performed the circulator seal malfunction (buffer-mid-buffer) switch operability check. The switches are normally calibrated on an annual basf s; however, due to the problems cited in the previous reports as listed on the LER, a check of buffer-mid-buffer trip settings on a monthly basis has been undertaken as an interim measure to test operability.

There are twelve buffer-mid-buffer switch units, three per circulator. Each switch unit contains two electrical switches. The range of the sensing ele-ment is from (-) 100 inches of water to zero to (+) 100 inches of water.

One of the electrical switches in each unit must operate at greater than or equal to (.-) 10 inches water (negative buffer-mid-buffer), and the other electrical switch must operate at less than or equal to (+) 80 inches water (positive buffer-mid-buffer) per Table 4.4-3.

The trip settings for the twelve switches are listed in Table 1 for July and in Table 2 for August.

~he switch settings, which were found to be less conservative that thcse established by the Technical Specification did not prevent the fulfillu nt of the functional requirements of the system.

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REPORTABLE OCCURRENCE 80-41 ISSUE O Page 2 of 5 CAUSE DESCRIPTION:

Dirt buildup and accumulation in the electrical switches prevented them from making proper contact.

CORRECTIVE ACTION:

The trip settings of the electrical switches were re-adjusted to the proper trip points.

Due to the continuing problems being experienced with the electrical switches, the interim check of the trip settings is being conducted on a monthly basis.

The investigation of the problem associated with the helium circulator seal malfunction trip cwitches has been completed, and Public Service Company Nuclear Project Department is proceeding on a path to replace the existing equipment.

No further corrective action is anticipated or required.

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REPORTABLE OCCURRENCE 80-41 ISSUE O Page 3 of 5 TABLE 1 As Found Inches H90 As Left Inches H2O Increasing Decreasing Increasing Decreasing Trip Point Trip Point Trio Point Trip Point 1A Circulator PDIS-21149 76 -8 76 -8 PDIS-21151 78 -8 78 -8 PDIS-21153 75 -5 75 -5 1B Circulator PDIS-21155 77 -6 73 -6 PDIS-21157 73 -30 @ 72 -5 PDIS-21159 72 -8 77 -8 1C Circulator PDIS-21150 75 -5 75 >5 PDIS-21152 75 -7 75 -/

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PDIS-21154 75 -3 75 -3 LD Circulator PDIS-21156 73 -7 73 -7

_PDIS-21158 74 -6 74 -6 PDIS-21160 75 -8 75 -8

@ Denotes switches which were out of tolerance.

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F REPORTABLE OCCURRENCE 80-41 ISSUE O Page 4 of 5 TABLE 2 As Found Inches H2O As Left Inches H2O Increasing Decreasing Increasing Decreasing Trip Point Trip Point Trip Point Trio Point lA Circuletor PDIS-21149 75 -5 75 -5 PDIS-21151 77 -8 77 -8 PDIS-21153 73 -17 @ 73 -6 13 Circulator PDIS-21155 82 O -6 78 -6 PDIS-21157 77 -7 77 -7 PDIS-21159 77 -9 77 -9 1C Circulator PDIS-21150 78 -4 78 -4 PDIS-21152 77 -9 77 -9 PDIS-21154 77 -8 77 -8 1D Circulator PDIS-21156 73 -50 @ 73 -5 PDIS-21158 75 -7 75 -7 PDIS-21160 75 -47 @ 75 -9 h Denotes switches which were out of tolerance.

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9 REPORTABLE OCCURRENCE 80-41 ISSUE O Page 5 of 5 Prepared By: ide Asa B. Jteed

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Technical Services Techtrician

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Reviewed By: / f' s

. W.'Gahm

/ Technical Services Supervisor Reviewed By: _ [yk - M f Frank M. ,Mathie / /

Operations Manager Approved By: 6, os Don Warembourg /

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Manager, Nuclear Production