ML20066H567
| ML20066H567 | |
| Person / Time | |
|---|---|
| Site: | San Onofre, Bailly  |
| Issue date: | 11/02/1982 |
| From: | Papay L SOUTHERN CALIFORNIA EDISON CO. |
| To: | Engelken R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V) |
| References | |
| 10CFR-050.55E, 10CFR-50.55E, 82-390, NUDOCS 8211230304 | |
| Download: ML20066H567 (2) | |
Text
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Docket Nos. 50-361/362
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50.55 (c) Report J'
RECE Il,y Southem Calltbmla Edison $onspanyj;;,,
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- u. O. mOx eoo 2244 WALNUT GROVE AVENUE 4
bkCJpg ROSEMEAD, CAUFORNIA 9177o tbvember 2,1982 s 'a * ** a'*
m.-.....,
Mr. R. H. Fnge lke n, Regional Administrator U. S. Nuclear Regulatory Commission Region V 1450 Maria Lane, Suite 210 Walnut Creek, California 94596-5368 De ar Mr. En gelk en:
S UBJECT:
Do cke t No. 50-361 and 50-362 San Onofre thclear Generating Station, Units 2 and 3 By letter to your office dated April 5,1982, we tran smitted a report regarding the possibility o f failure of Lumigraph instrinnent indicators which we had previously reported to you as a potentially significant deficiency in accordance with 10C FR5 0. 5 5(e).
Further developnents have caused changes to the corrective action we are taking regarding the reported condition.
Consequently, a ttached are twenty-five (2 5) copies o f a supplemental report entitled " SUPPLEMENTAL REPORT ON SIG4A MODEL 9270 INDICATOR RESISTER PROBLEM, San Onofre Nuclear Generating Station, thits 2 and 3."
If you have any questions regarding this report, we would be happy to discus s them at your convenience.
4 Very truly yours,
TV At tac hmen t s cc:
Victor Stello (NRC, Director I&E)
A. E. Chaffee (NRC, San Onofre Units 2 and 3)
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L 8211230304 821102 i'g-PDR ADOCK 05000361 S
PDR t
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SUPPLEMENTARY REPORT ON SIGMA MODEL 9270 INDICATOR RESISTOR PROBLEM San Onofre Nuclear Generating Station, Units 2 and 3 INTRODUCTION By letter dated April 5, 1982, Southern California Edison trans-mitted a report regarding the deterioration of the carbon-type electrical resistors in model 9270 Lumigraph instrument indica-tor which could, over a period of time, cause the indicators to malfunction.
That report recorded the results of investigation of causes, analysis of safety implications, and corrective ac-tion to be taken.
This supplementary report revises the comple-tion date of the corrective action which has been developed as a result of further field investigation.
CORRECTIVE ACTION The final completion date for replacing the resistors, recali-brating the instruments and the system loop retesting for both units will be April 1, 1983.
The potential deficiency identified with the Sigma indicators was related to specific resistors which, due to their carbon composition, could overheat and change value.
However, the ven-dor stated that no short-term malfunctions should be expected since the potential problem has been observed after one to several years of full power services.
Since SONGS 2 and 3 are not under full power operation, the integrated value of overheat and service time for the resistors would not exceed the value of one-year full power operation if these resistors were replaced i
prior to April 1, 1983.
So far no indicator malfunctions have I
occurred due to the above problem at SONGS 2 and 3; therefore, we are confident that this deficiency will not occur prior to April 1, 1983.
I 1497Q