ML17252A879

Letter Regarding a 11/18/1973 Occurrence Relating to the Discovery of the Erroneous Setting for 1 of the Bistables Associated with Low Pressurizer Safety Injection Required by the Technical Specifications - Indian Point Unit No. 2

ML17252A879
Person / Time
Site:	Indian Point
Issue date:	12/03/1973
From:	Cobean W Con Edison, Consolidated Edison Co of New York
To:	O'Leary J US Atomic Energy Commission (AEC)
References
3-2-16
Download: ML17252A879 (1)

Text

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• Consolidated Edison Company of New York, Inc.

4 Irving Place, New York, NY 10003 December 3, 1973 Re: Indian Point Unit No. 2 Facility Operating License DPR-26 A.O. 3-2-16 50-247

~egulatory File **cy.

Mr. John F. O'Leary Directorate of Licensing Off ice of Regulation

u. S. Atomic Energy Commission Washington, ,D. C.* 20545

Dear Mr. O'Leary:

The following report is provided pursuant to the requirements of Section 6.12.2(a) of the Technical Specifications of Facility Operating License DPR-26.

On November 18, 1973, following an analysis of the results of periodic tests and calibration checks relating to pressurizer pressure it was found that the setting for one of the three bi-stables associated with low pressurizer pressure safety injec-tion was below that required by Item 3 in Table 3-1 of the Tech-nical Specifications. At the time of these periodic tests and calibration checks, the reactor was in the cold shutdown con-dition for maintenance work.

The bistable that had an erroneous setting is part of a two-out-of-three logic system which provides for a safety injection sig-nal on coincident low pressurizer pressure and low pressurizer level. The other two bistables were operating correctly. The channel associated with this device was .recalibrated and retested satisfactorily.

Safety implications of this occurrence are considered to be slight since the remaining two channels of the two-of-three actuation log-ic were properly set and would have functioned if required. In-vestigations into the reason for the low setting have not as yet yielded a d~~j..n_i te cause and are being contimJed.

Very truly yours, DOCK mo USAEC tJ5~~*

Warren R. Cobean, Jr.,

Manager, Nuclear Power Generation 8700