ML20097F838
| ML20097F838 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 06/08/1992 |
| From: | Rosenblum R SOUTHERN CALIFORNIA EDISON CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| NUDOCS 9206160075 | |
| Download: ML20097F838 (1) | |
Text
f:ME Southem Califamia Edison Company 23 f>AF4KrH STO& rt IRVINE, C AltPOF4NIA W710 nuru g ueu June 8. 1992
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- ft.CL L AR $4EdliLATLe84V Art mpig U. S. Nuclear Regulatory Commission Document Control Desk Washington, D. C.
20555
Subject:
Docket No. 50-361 Special Report San Onofre Nuclear Generating Station, Unit 2 This report is being submitted according to Technical Specification (TS) 3.3.3.3, Action a, of facility Operating 1.icense NPF-10, San Onofre Unit 2.
The TS requires Southern California Edison (SCE) to submit a Special Report when the seismic monitoring instrumentation becomes inoperable for more than 30 days.
On May 7, 1992, with Unit 2 in Mode 1 at 100% power, steam generator base support strong motion accelerometer (SMA) 2XT-8020B was-determined inoperable following performance of a routine monthly surveillance test.
Specifically, the instrumentation did not respond to the calibration signal nor the natural frequency signal as required by. Procedure S023-11-2.1.
Investigation results to date have not been able to establish when the SMA failed.
Initial troubleshooting of the seismic instrumentation components and circuitry could not fully determine the cause of the deficiency. -Further troubleshooting will require containment entry for accessing 2XT-8020B. Due to ALARA considerations during power operations, personnel are precluded from performing further investigative efforts. Troubleshooting and repair efforts for 2XT-8020B will be performed during the next Unit 2 shutdown of sufficient duration or the next Unit 2 refueling outage as allowed by Surveillance R?quirements, 4.3.3.3.2.
If you require any additional information, please let me know.
Very truly yours, h)H cc:
J. B. Martin, Regional Administrator, NRC Region V M. B. Fields, NRC Project Manager, San Onofre Units 2 and 3 C. W. Caldwell, NRC Senior Resident Inspector, San Onofre Units 1, 2&3 dp '?$
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