05000267/LER-1981-008, Forwards LER 81-008/03L-0

Forwards LER 81-008/03L-0

ML20003B844
Person / Time
Site:	Fort Saint Vrain
Issue date:	02/19/1981
From:	Warembourg D PUBLIC SERVICE CO. OF COLORADO
To:	Seyfrit K NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
Shared Package
ML20003B845	List: 05000267/LER-1981-008, Forwards LER 81-008/03L-0
References
NUDOCS 8102250669
Download: ML20003B844 (6)

LER-1981-008, Forwards LER 81-008/03L-0

Event date:
Report date:
2671981008R00 - NRC Website

text

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PLATTEVILLE, COLOR ADO 80651 r

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February 19, 1981 Fort St. Vrain

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Unit No. 1 P-81058 Mr. Karl V. Seyfrit, Director Nuclear Regulatory Co= mission Region IV Of fice' of Inspection and Enforcenent 611 Ryan Plaza Drive Suite 1000-Arlington, Texns 76012 Reference: Facility-Operating License No. DP R-3!+

Docket No. 50-267

Dear Mr. Seyfrit:

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

81-008, Final, subnitted per the requirenents of Technical Specification 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. 50-267/31-008.

Very truly yours, CL '

Don Warenbourg Manager, Nuclear Production DW/ cis Enclosure' 03 cc: Director, MI?c S

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8102 25 oGrq

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REPORT DATE:

February 19, 1981 REPORTABLE OCCURRENCE 31-008 Determined ISSUE 0 OCCL'RRENCE DATE:

Janua ry 20, 1981 Page 1 of 5 FORT ST. VRAIN NUCLEAR GENERATING STATION PUBLIC SERVICE C0}TANY OF COLORADO 16805 k' ELD COUNTY ROAD 19 1/2 PLATTEVILLE, COLORADO 80651 REPORT NO. 50-267/ 81-008/03-L-0 Preliminary IDENTIFICATION OF OCC'!RRENCE :

k'hile the reactor was in a shutdown condition, routine surveillance testing of the primary coolant progrs==ed pressure scram revealed that three of the pressure transmitters were out of calibration and could have ellowed oper-ation with trip setpoints less conservative than required by LCO 4.4.1, Table 4.4'-1.

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

E7ENT' DESCRI? TION:

'(See Figure -1)

While perfor=ing the annual calibration of the primary coolant pressure scram channels, plant instrument personnel observed that three of the pressure transmitters @ were out of calibration in the non-conservative direction.nd would have resulted in the pressure switch highs 2 tripping at.a higher pressure than allowe by the LCO. require =ents.

The low reading o@f the pressure transmitcers.

I would have caused the pres-sure switch lows to trip sooner at a higher, = ore conservative pressure than required.

~ The high and low pressure trips @ and @ are orogra==ed by circulator in-let te=perat' re thr ugh an auctioneer circuit 4 and a histable setpoint p ro gra:mne r 5 or 6 The programmed pressure temperature curve is shown in Figure 2.

The low output signal from the pressure transmitter could have resulted in the hi h oressure. trips occurring above the allowable high pres-sure curve (line A @ ).

Th pressure trips would have occurred above

. low pressure trip curve (line

) in a conservative direction.

Although the high pressure trips could are occurred'at a value less con-servative than that established in the Technical Specifications, they.would not prevent the fulfillment of the functional requirements of the system.

4 i

REPORTABLE OCCURPINCE SI-008 ISSUE O I

CAUSE

- DESCRIPTION :

The icv pressure signals were due to instrutent drift of the pressure trans-

' nitter.

CORRECTIVE i

ACTION :

k a

The pressure transmitters were calibrated during the procedure, returned to

' se:vice, and the surveillance test was successfully co=pleted.

Once' a :acnth, on a tenporary basis, the pressure trans=1 ter voltage outputs

' vill be checked against. reactor pressure to determine if further instrument drift is occurring. The :nonthly test will be conducted until the next regu-j larly -scheduled surveillance calibration is required or until it is deter-

' mined that instru=ent drif is - not occurring.

1 The.results vill be included.in :a future supplemental report.

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REPORTA3LE OCCURRENCE 81-069 ISCUE O REACTOR PRESSURE CIRCULATOR I NL ET TE'4PER ATURE 5h (PROPORTIONAL TO PLANT LCAD)

CHRCMEL/[CNSIANTAN

POTENTIOMETRIC THER*0COUDLES LCCATED or

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TRANSOUCER IN WELLS IN P:Rv LCaER HEAD

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TEST C MAIN CONTRCL 1r ir ROOM FT TT TT AM*LIFIER AM PLI F I ER AMPLIFIER h

DI 0 INDICATOR AUCil0NEER 1Ir CSI 9 SISTABLE SETPolNT SISTABLE SETPotNT PROGRA&ER (WITH TM TH PROGRAMMER (~.ITH HIGH AND LOW HlGH Agg (Ow t

LIMITS)

LIMITS) 01 SETPolNT

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SET AT INDICATOR 300 PSIA 1r 1r 1r PS PS H PS

pg SISTABLE BISTABLE BISTABLE SETPOINT INDICATCR M

Y hy TC PCRV TO LOOP TO SCRAM PELIEF VALVE SHUTOCWN CHANNEL "A" INTERLOCK AND STEAM /

(2 CF 3)

WATER CUMP CIRCULI (2 0F ?)

CIRCUITRY Reac:cr' pressure in ru=en: _ channel (typ. fer channels 3&C)

FIGURE 1

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fj5 PSIAB UPPER

!!lIllGil PRESSUREf lSEIPolNT sy

@ TRIP CURVE 100% LlHII 700 a 75%

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10 ia NORi1AL j! LOW REACTOR ll 3

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j! PRESSURE s.k"'::;;

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LOWER PRESSURE d

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CIRCULATOR INLET TEMPERATURE (*f) dn 01 Fig. 7.1-14--Programmed reactor preneure high-low trip points b

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REPORTABLE OCCURRE' ICE S1-008 ISSUE O Page 5 of 5 J

Prepared Sy:

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Reed.

Technical Services Technician 3

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o Reviewed By:

,/ Sw l W.f,;ahr Technical Services Supervisor Reviewed Sy:

Frank M. Mathie Operations Manager Apptoved By-Mu~[u

. Don - Warenbo urg

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Manager, Nuclear Produe:1on d

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