ML20037B774
| ML20037B774 | |
| Person / Time | |
|---|---|
| Site: | Beaver Valley |
| Issue date: | 11/24/1980 |
| From: | Werling J DUQUESNE LIGHT CO. |
| To: | Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| References | |
| BVPS:JAW:1037, RO-80-085-01P, RO-80-85-1P, NUDOCS 8012010300 | |
| Download: ML20037B774 (2) | |
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seest m e ssee w em DUQUESNE LIGNT CCHPANY 3eaver Valley Power Stat! !
Post Office Box 4 m.
- Shippiasport, PA 13077 -
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- r_.#2. 1.:.:;.n:xAccumrnsm:M4::" ""rkcN:nc.h 'av%*.'.nu.a*.www:sacias4 Novoueer 24, 1980 EVPS: JAW:1037 Beaver Valley Power Station Unit No.1 Docket No. 50-334, Licer.se No. DPR-66 LER 80-085/01F Mr. 3. R. Criar Dmited States Nuclear Regulatory M aston Besion 1 631 Park Avenue Eing of Prussia, Pennslyvants 19406
Dear Mr. Crier:
In accordance with Appandir A, 3eaver Valley Technical Specifications, LIR 80-085/01P is being submitted. 'This occurence was reported to Mr.
I D. A. Beckansa, the Beaver Valley Resident Inspector, at 1120 hours0.013 days <br />0.311 hours <br />0.00185 weeks <br />4.2616e-4 months <br /> on W 21, 1980.
At err.e4.mately 0600 hours0.00694 days <br />0.167 hours <br />9.920635e-4 weeks <br />2.283e-4 months <br /> on November 20, 1980 an operator observed that (2/4) two of four nuclear instrumentation power range channels were reading signifienntly higher than the others.
N41 and N42 were indicating appwminately 3%, while 343 and N44 indicated 0% power.
After esiling for instr ament e py-s i., it was discoverad that there was ino high voltage input to the detectors of either ch==aels N43 or N44.
The taek of high voltage indicated that the design high voltage protec.':1on circuit has de m gized the detectors. High voltage was removed from the circuit, whfeh in turn resets the " crowbar" circuit.
The circuit was then r: :
. ised and the k==a=1s checked, both were normal. All circuits were returned to I
normal at 0615 hours0.00712 days <br />0.171 hours <br />0.00102 weeks <br />2.340075e-4 months <br />.
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Bec. 3. N. Crier 3evember 24, 1980 SWPS: JAW 1037 Page 2 Cause has not, been established for this incident and is still being '
investigated.
Failure of these t,e of four channels would have reduced the.
member of cha-la available to perform say ' protective function by one-half..
l Prior to.a Reactor trip and safety fajection' incident ce November 17, 1980 l
the Wuclear Shif t Supervisor personally channel checked all the power ra' age instruments were indicating properly.
This was the first startup since that Lacident.
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Very truly yours, J. A. Werling Superintendent' ces Director Of Management I, Program Analysis United States Nuclear Regulatory Commission Usshington, D. C.
20555 W. J. Ross, trirFS Licensing Project tianager theited States Fuclear Regulatory ~ Commmission washingten, D. C.
20555 D. A. 1k h a, Duclear Regulatory Commission. BVPS Site " Inspector P. Riggins, secretary, Prime Nevers Committee - EZI smelaar Safety Analysis Center, Palo Alto, California 3er Jolma Alford, PA Public Utilities Commaission, Harrisburg, PA l
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