ML20084A252

AO 3-2-17:on 731217,one Bistable Setting Exceeded Tech Spec Limit of 92% Span.Caused by Instrument Drift.Channel Recalibr & Investigation Initiated for Detailed Analysis of Instrument Capabilities

ML20084A252
Person / Time
Site:	Indian Point
Issue date:	12/18/1973
From:	Cobean W CONSOLIDATED EDISON CO. OF NEW YORK, INC.
To:	James O'Reilly US ATOMIC ENERGY COMMISSION (AEC)
Shared Package
ML20084A234	List: ML20084A232 ML20084A252
References
AO-3-2-17, NUDOCS 8304050141
Download: ML20084A252 (2)

Text

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(? CU be U Consolidate:I Edison Company of Now York. Inc.

4 i Ang P! ace, N York, N Y 10003 d

December 18, 1973 Re: Indian Point Unit No. 2 Facility Operating License  ;

DPR-26 A.O. 3-2-17 . .

Mr., James P. O'Reilly, Director ..

Regulatory Operations, Region I U. S. Atomic Energy Commission 631 Park Avenue King of Prussia, Pennsylvania 19406 '

Dear fir. O'Reilly,

The following report of Abnormsl-Occurrence No. 3-2-17 is provided purauant to the requirements of Section G.12. 2 (a ) of the Technical Specifications to Facility Operating License No.

DP R- 2 6 .

On December 17, 1973 an analysis of the results of periodic tests and calibration checks relating to pressuriser level in-dicated that the setting for one of three bistables associated with high pressurizer level reactor trip was slightly above that required by Technical Specificat ion 2. 3.1.C (l) . At the time of theoc periodi-c tests and calibration checks, the reactor was in .

the coldto repairs shutdown the feedwaterconditionpiping for maintenance for No 22 steamwork associated with generator.

This particular bistable device is part of a two out of three logic system which provides for a reactor trip signal on high pres-suriter level.

The setpoint was found to be at 92.25% of span in-stead of the 192t of span required by the Technical Specifications.

The other two bistables of the system were found to be operating correctly.

and re'estedThe channel associated with this r*avice was recalibrated satisfactorily.

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. We Grift strument believe'the obcerved discrepancy to be the result of in- .-

an! have reques*ed our Engineering Department to provide a detailed analyses of the capability of the instrument buses to sustain the applied loading and the harmonic wave effect on power syplies, b3ntables, converters etc. As part of the analy-

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ses, the offect of voAtage swings on the equipment listed abovo l

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Mr. James P. O'Reilly O O December 18, 1973 Re Indian Point Unit No. 2

, Facility Operating License DPR-26 A.O. 3-2-17 will be evaluated. Based on these analy'ces, appropriate cor-rective action will be taken. Mr. Bert Davis of your office was notified of this occurrence by Mr. John Mahopeaco by tele-phone on December 17, 1973.

Very truly yours,

\

j y' O(L% % M o ~, ks GLW Warren R. Cobean, Jr., Manager Nuclear Power Generation cc: Mr. John F. O' Leary

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