ML20100L598
| ML20100L598 | |
| Person / Time | |
|---|---|
| Site: | Harris  |
| Issue date: | 03/14/1985 |
| From: | Parsons R CAROLINA POWER & LIGHT CO. |
| To: | Grace J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| CON-NRC-333, REF-PT21-85, REF-PT21-85-188-000 190, PT21-85-188, PT21-85-188-000, NUDOCS 8504170067 | |
| Download: ML20100L598 (4) | |
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Carolina Po erd 8, m 7= "
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iqht, Company P. O. Box :.dl, New Hill, N. C.
27562 March 14, 1985 Dr. J. Nelson Grace NRC-333 United States Nuclear Regulatory Commission Region II 101 Marietta Street, Northwest (Suite 2900)
Atlanta, Georgia 30323 9
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CAROLINA POWER & LIGilT COMPANY d
SilEARON llARRIS NUCLEAR POWER PLANT
[
1986 - 900,000 KW - UNIT 1 7.5 KVA INVERTERS -
CAPACITOR TERMINATIONS, ITEM 190
Dear Dr. Grace:
Attached is our third interim report on the subject item which was deemed reportable per the provisions of 10CFR50.55(e) and 10CFR, Part 21, on October 24, 1984. CP&L is pursuing this matter, and it is currently projected that corrective action and submission of the final report will be accomplished by April 19, 1985.
Thank you for your consideration in this matter.
Yours very truly, g
R. M. Parsons Project General Manager Completion Assurance Shenran liarris Nuclear Power Plant RMP/bc
.\\ttachment cc: Messrs. G. Maxvell/R. Prevatte (NRC-SilNPP)
Mr. R. C. DeYoung (NRC) l 8504170067 850314 gDR ADOCK 05000400 PDR I
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CAROLINA POWER & LIGHT COMPANY SHEARON HARRIS NUCLEAR POWER PLANT UNIT NO.1 THIRD INTERIM REPORT 7.5KVA INVERTER CAPACITOR TERMINATIONS CQL-8255 NCR 84-2486 ITEM NO.190 MARCH 15,1985 REPORTABLE UNDER 10CFR50.55(e) AND 10CFR21 ddll/2 1
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SUBJECT:
Shearon Harris Nuclear Power Plant / Unit No. I 10CFR50.55(e) and 10CFR Part 21 reportable deficiency. 7.5KVA instrument inverter tuning capacitor terminations are such that a seismic event could result in a significant drop in inverter output voltage. This would result in the loss of ESF instrumentation, RPS, and NIS.
ITEM:
Ferroresonant transformer to tuning capacitor connections in 7.5KVA static inverters.
SUPPLIED BY:
Westinghouse Nuclear Service Division NATURE OF DEFICIENCY:
During the manufacture of 7.5KVA static inverters with non-PCB capacitors, ferroresonant transformer leads using fast-on terminals were, on some occasions, connected to tuning capacitor solder lugs.
This resulted in deformed solder lugs and compromised the seismic qualification of the inverter.
SCOPE OF PROBLEM:
Investigation of this problem revealed deficiencies in three of four instrumentation inverters and two BOP inverters.
For the nonsafety inverters, this deficiency represents an operational limitation.
DATE PROBLEM OCCURRED:
Westinghouse notification of October 5, 1984 was followed by inspection and verification of problem on October 22,1984.
DATE PROBLEM REPORTED:
On October 24,1984, CP&L (N. 3. Chiangi) notified the NRC (Mr.
A.
Hardin) that the above item was reportable under 10CFR50.55(e) and 10CFR Part 21.
SAFETY IMPLICATIONS:
Loss of three of four inverters results in a loss of safety-related RPS, nuclear instrument system (NIS), and other safety-related vital instrumentation and control required for safe shutdown.
REASON DEFICIENCY 15 REPORTABLE:
Failure of the supplier's QA program to control internal electrical termination practices resulted in equipment being shipped to the site which deviated from the supplier's specifications and inspection criteria.
Such deviation, by analysis, results in compromised safety systems and functions.
l ddll/3 t
e CORRECTIVE ACTION:
Westinghouse Technical Bulletin TB-84-08 has been issued as previously reported. The solder lug to fast-on terminal connections have been corrected. An ancillary problem developed during the
" pull test".
An attempted implementation of this recommended action resulted in NCR-84-2486 after several fast-on to fast-on capacitor connections failed to meet the 20-pound criterion.
Af ter discussions with Westinghouse on pull test methodology, the conclusion reached was to reperform this test with the 20-pound passing standard. The connections again failed to meet the 20-pound criterion.
A suggested redesign was forwarded to Westinghouse in an effort to preclude the pull test. This redesign was reviewed and not accepted in favor of the results of a reanalysis of connection requirements.
This reanalysis shows that a 5 pound criterion provides a conservative margin for seismic requirement.
. FINAL REPORT:
The final report on this item is pending successful disposition of the pull test.
Because of the difficulties encountered, the projected final report date has been moved to April 19,1985.
1 I
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