ML20063D921
| ML20063D921 | |
| Person / Time | |
|---|---|
| Site: | Fermi  |
| Issue date: | 08/18/1982 |
| From: | Wells D DETROIT EDISON CO. |
| To: | James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| References | |
| 10CFR-050.55E, 10CFR-50.55E, EF2-59386, NUDOCS 8208300080 | |
| Download: ML20063D921 (1) | |
Text
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August 18, 1982 EF2-59386 Mr. James G. Keppler, Regional Mministrator Region III
_.U.S. Nuclear Regulatory Comission 799.Rooseveit Road Glen Ellyn, Illinois 60137
Subject:
Interim Report of 10CFR50.55(e) Item on Rosemount Trip Units (#75)
Dear.Mr. Keppler:
On July 20, 1982, Detroit Edison's Mr. G.M. Trahey, Assistant Director-Project Quality Assurance, telephoned Mr. J. Konklin of NRC Region III to report on a potential problem with Reactor Pressure Trip Units at the-Fermi 2 site.
During calibration of Rosemount Model 510 DU Trip Units, it was determined that a high percentage could not be calibrated. Without circuit analysis, Engineering is unable to determine whether or not, if uncorrected, the problem would prevent the unit frm performing its function properly.
Based on preliminary evaluation, the cause is balieved to be oxidation of-the trip set point adjusting potentiometer windings due to inadequate storage environment. Investigation is incmplete at this time. Additional informa-tion will be provided upon completion of investigation.
Another report on this item, either interim or final, is scheduled to be sent to you on or before December 16, 1982. If you have questions concerning this matter, please contact Mr. G.M. Trahey, Assistant Director-Project-Quality Assurance.
-Very truly yours, f t l
DAW /DF/cp d
cc: Mr. Richard DeYoung, Director Office of Inspection and Enforcement Division of Reactor Inspection Programs Washington, D.C. 20555 Mr. Bruce Little, Resident Inspector U.S. Nuclear Regulatory Comission 6450 North Dixie Highway, Newport, Michigan 48166
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