ML20086G434
| ML20086G434 | |
| Person / Time | |
|---|---|
| Site: | Peach Bottom  |
| Issue date: | 07/18/1975 |
| From: | Cooney M PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC |
| To: | Anthony Giambusso Office of Nuclear Reactor Regulation |
| References | |
| AO-50-277-75-53, AO-50-278-75-40, NUDOCS 8401110415 | |
| Download: ML20086G434 (2) | |
Text
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PHILADELPHIA ELECTRIC COMPANY 2301 MARKET STREET PHILADELPHI A. PA.19101 s.
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July 18, 1975 JUL231975 i-- 9
- 8. D N I 79 Mr. A. Giambusso
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Director Division of Reactor Licensing (G
Office of Nuclear Reactor Regulations United States Nuclear Regulatory Commission Washington, DC 20555
Dear Mr. Giambusso:
Subject:
Abnormal Occurrence The following occurrence was reported to Mr. Walt Baunack, Region 1, Office of Inspection and Enforcement, United States Nuclear Regulatory Commission on July 9, 1975 Written notification was made to Mr. James P. O'Reilly, Region 1, Office of Inspection and Enforcement, United States Nuclear Regulatory Commission on July 10, 1975 In accord-ance with Section 6 7 2.A of the Technical Specifications, Appendix A of DPR-M and DPR-56 for Unit 2 and Unit 3 Peach Bottom Atomic Power Station, the following report is being submitted to the Directorate of Reactor Licensing as an Abnormal Occurrence.
Reference:
License Number DPR-M and DPR-56 Technical Specification
Reference:
3.ll.A.1 Report No.:
50-277-75-53 and 50-278-75-40 Report Date:
July 18, 1975 Occurrence Date: July 9,1975 Facility:
Peach Bottom Atomic Power Station R.D. 1, Delta, Pennsylvania 17314 Identification of Occurrence:
l Failure of the
'B' Control Room Emergency Ventilation Fan damper solenoid coil and fan control power transformer.
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_C_onditions Prior to Occurrence:
j Both Units 2 and 3 at approximately 50% power.
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Description of Occurrence:
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.9 During a periodic equipment check after solenoid valve
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maintenance, the indicating lamps for fan running status were observed b
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to be out.
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.bm.Mr.A.Giambuss 50- 53 & 50-278-75-40 July 18, 1975 Page 2 Designation of Apparent Cause of Occurrence:
Investigation determined that the control power transformer had shorted to ground due to failure of a solenoid coil in the "B" Control Room Emergency Ventilation Fan damper circuit. The f an damper valve was found to have excessive air leakage past the seat and plunger, thus causing the plunger to be forced out of the electromagnetic field of the energized solenoid coil. and causing the coil to burn out.
Analysis of Occurrence:
Safety significance of this incident is minimal because the
'A' fan is operable and both filter trains are available for service.
A backdraft damper in each loop precludes recirculation in the failed loop.
Corrective Action:
The 480 - 120V control circuit transformer, the solenoid valve and coil was replaced and satisfactory fan operation was verified.
Failure Data:
None.
Very truly yours, ff/
H. J Cooney A
t Gen'1 Superintendent Generation Division cc:
Mr. J. P. O'Reilly Director, Region 1 Office of Inspection and Enforcement 4
United States Nuclear Regulatory Commission 631 Park Avenue King of Prussia, PA 19406
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