B13621, Part 21 Rept Re Substantial Safety Hazard Involving Westinghouse Veritrek Transmitters.Large Shift in Output Observed While Attempting to Calibr Two Transmitters. Internal Review Performed & Defective Transmitters Replaced

Part 21 Rept Re Substantial Safety Hazard Involving Westinghouse Veritrek Transmitters.Large Shift in Output Observed While Attempting to Calibr Two Transmitters. Internal Review Performed & Defective Transmitters Replaced

ML20059D161
Person / Time
Site:	Millstone
Issue date:	08/27/1990
From:	Mroczka E NORTHEAST NUCLEAR ENERGY CO., NORTHEAST UTILITIES
To:	Martin T NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
References
REF-PT21-90 B13621, NUDOCS 9009060114
Download: ML20059D161 (3)

Text

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EM General Offices

• Selden Street, Berkn Connecticut U,YNNei$i [c c5*~a . P.O. BOX 270

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- HARTFORD, CONNECTICUT 06141-0270  !

k L J [$f$U.,7, Z' (203) 665-5000 August 27, 1990 Docket No. 50-423 B13621 4 Re: 10CFR21 Mr. Thomas T. Martin Regional Administrator, Region I

• U.S. Nuclear Regulatory Commission 475 Allendale Road King of Prussia, PA 19406

Dear Mr. Martin:

Millstone Nuclear Power Station, Unit No. 3 Report of Substantial Safety. Hazard ,

Westinahouse Veritrek Transmitters In conformance with 10CFR21, Northeast Nuclear Energy Company (NNECO) hereby '

provides notification of a substantial Safety Hazard (SSH) at the Millstone Unit No. 3 plant.

""  ?.. Vegel of the- NRC Region I Office was verbally notified August 24, 1990 of two Veritrek transmitters which, based upon responses during calibration and special test, were determined to have excessive output shifts relative -to ,

changes in ambient temperature. These problems were identified during j routine surveillance.

The following information applicable to this -SSH is provided as outlined by l 10CFR21.21(b)(3) i through viii: 4 (i) Name and Address of Individual Informino 'the Commission' E. J. Mroczka, Senior Vice President, ' Northeast- Nuclear Energy ,

Company, P. O. Box 270, Hartford, Connecticut 06141-0270.

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-(ii) Identification of Basic Comoonent Westinghouse Veritrek Transmitter Model Number: 76DP2 1

(iii) Identification of Firm Suoolvina the Basic Comoonent -)

L The supplier of the subject transmitters -was Westinghouse- Electrir l Corporation,. Water Reactor . Divisions, . Box 355, Pittsburgh, PA 15230-0355. However, Westinghouse has sold <this line of transmitters to Tobar, Inc.,1441 West Alameda Drive, Tempe, AZ 85282.

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Mr. Thomas T. Martin B13621\Page 2 i August 27, 1990  ;

(iv) Nature of Failure and Safety Hazard Created While attempting to calibrate two ' transmitters, an apparent large shift in output was observed when the transmitters' covers were removed or replaced. In. evaluating tt.e response of these two trans- l mitters, it was determined that replacement was required due to the -

observed changes in output with cover removal and replacement, j Following removal, one of the two defective transmitters was subjected to a screening test which determined that there was . a significant~ q change in transmitter output corresponding to changes in temperature l effects.  !

As a result of temperature effect ' problems identified at Publ ic -

Service of New Hampshire's(ppabrook facility in 1986, and reported to the NRC via 10CFR50.55(e), ". Westinghouse conducted extensive testing. I on the transmitter and modified the. " allowable Temperature Compensation value" to- ensure operability of the transmitters.

However, even with these new values, it can reasonably be expected .

that these two transmitters would not have. performed as specified. l These transmitters provide input to the reactor -trip .and engineered safety features actuation logic. The trip setpoints for the _above are t based on the maximum assumed error (including errors due to temperature affects) plus a margin. The excessive ambient temperature calibration chifts could create a condition that would violate allowable technical specification limits.

(v) Date on which Information of Failures was Obtained NNECO completed a- substantial safety hazard (SSH) review on August 22, 1990, and determined that the defect constituted an SSH- and- was reportable under 10CFR21.

(vi) Number and location of all Veritrek Transmitters There are nineteen Veritrek transmitters installed at Millstone Unit No. 3 to monitor parameters such as steam generator level and reactor coolant system pressure.

An internal review has been performed and it has been determined that i these transmitters are not utilized in any of Northeast Utilities' l other nuclear units. '

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(1) J. DeVincentis (PSNH) letter to R. W. Starostecki, " Interim 10CFR50.55(e) Report: Pressure Transmitters," dated April 10, 1986.

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Mr. Thomas T. Martin ,

B13621\Page3 r August 27, 1990 1 (vii) Corrective Action. Responsible Oraanization The two defective transmitters were replaced with similar units from spares. The two spares were checked prior to installation for temper-ature sensitivity and found to meet manufacturers specifications. '

s (viii) Advice Related to Failure Given to licensees ,

Not applicable--refers to suppliers.

I trust this fulfills our reporting obligations in accordance with 10CFR21 and is fully responsive to your needs for such information.

Very truly yours, NORTHEAST NUCLEAR ENE Y COMPANY s} ~

E 'U.jfir6c~zka 47 Seni6r Vice President cc: T. E. Murley, Director, Office of Nuclear Reactor Regulation D. H. Jaffe, NRC Project Manager, Millstone Unit No. 3 W. J. Raymond, Senior Resident Inspector, Millstone Unit Nos. 1, 2, and 3 A. Vegel, Reactor Engineer, NRC Region 1 U.S. Nuclear Regulatory Commission Document Control Desk Washington, DC 20555 Westinghouse Electric Corporation Nuclear Services Division- i Box 355 Pittsburgh, PA 15230-0355 Tobar Inc.

1441 West Alameda Drive Tempe, AZ 85282 i

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