ML20133B484
| ML20133B484 | |
| Person / Time | |
|---|---|
| Site: | Bellefonte  |
| Issue date: | 09/19/1985 |
| From: | Hufham J TENNESSEE VALLEY AUTHORITY |
| To: | Grace J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| NUDOCS 8510030300 | |
| Download: ML20133B484 (2) | |
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'D 2N4P @g4,%d319,1985 BLRD-50-438/85-25 BL5tD-50-439/85-22 U.S. Nuclear Regulatory Commission Region II Attn:
Dr. J. Nelson Grace, Regional Administrator 101 Marietta Street, NW, Suite 2900 Atlanta, Ceorgia 30323
Dear Dr. Grace:
BELLEFONTE NUCLEAR PLANTS UNITS 1 AND 2 - UNDERVOLTAGE OF THE 125V DC VITAL POWER DISTRIBUTION SYSTEM TO AUKILIARY FEEDWATER TURBINE PUMP ROOM COOLING FANS - BLRD-50-439/85-25, BLRD-50-439/85 FIRST INTERIM REPORT The subject deficiency was initially reported to NRC-OIE Inspector Al Ignatonis on August 6, 1985 in accordance with 10 CFR 50.55(e) as Significant Condition Report (SCR) BLN EEB 8510.
Enclosed is our first interim report. We expect to submit our next report on or about March 21, 1986.
If you have m y questions, please get in touch with R. H. Shell at FTS 858-2688.
Very truly yours, TENNESSEE VALLEY AUTHORITY
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W. Hufham, Manager Licensing and Risk Protection Enclosure cc:
Mr. James Taylor, Director (Enclosure)
' Office of Inspection and Enforcement U.S. Nuclear Regulatory Commission Washington, D.C.
20555 Records Center (Enclosure)
Institute of Nuclear Power Operations 1100 circle 75 Parkway, Suite 1500 Atlanta, Georgia 30339 8510030300 850919 DR ADOCK O 8
DR An Equal Opportunity Employer I
r ENCLOSURE BELLEFCNTE NUCLEAR PLANT UNITS 1 AND 2 UNIER70LTAE & TE 125V DC VITAL P0iER DISTRIBUTICH SETEM TO AUXILIARY FEEDiATER TLRBINE PlNP ROOM 000 LINO FA!6 BLRD-50-4 3 8/85 -2 5 AND B LRD-50439/85-22 SG BLN EEB 8510 10 T R 50. 55(e )
FIIET INTERIM EPORT l
Demrip tion of Defic iercl The design configration of the 125V de vital power distritution system (EU) provide a 104.5V do tennimi voltap. This low s our ce vol tam co upl ai wi th the existing cable voltap drop results in imufficient voltap to the auxiliary Teedwater txbine pump ( AFTP) room cooling f an motors. The insufficient voltag reduces the (noling carncity of the ram and could result in a hidi tenperature environment for the AFTP controls.
The apparent cause of this deficiency appears to be a f ailme to consider the eff ects of cable vol tag dro p in the dmim of the f eeder cable ci rcui ts to the AFTP nxxn. cooling f ans.
Interim P rag ress TVA is evalmting the subject condition to detennine a storter path for cable installation between the 125V do vital power distritution systen and the AFTP room cooling f am motors. A shorter cable route would result in a smaller cable voltag drop and restore the re(pired cooling capacity of the AFTP room cooling f am.
All deir work on this deficiency will be complete in Janmry 1986 for unit I and P etr ary 1986 f or unit 2.
Construction corrective action on this deficiency is scheduled to be complete by Ferrmry 14, 1986, f or mit 1 and August 30, 1992, f or unit 2.
In order to prevent a recurrenm of groblens of this nattre, IV A has pe rf onn ei vol tap dro p cal cul at i ons for al1 s af et y-rel at el ca bl es at Belleronte N uci ear P lant.
Additianal infonnation will be provided to the NRC on or about March 21, 1986.
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