ML20086K401
| ML20086K401 | |
| Person / Time | |
|---|---|
| Site: | Peach Bottom  |
| Issue date: | 07/24/1974 |
| From: | Ullrich W PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC |
| To: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| Shared Package | |
| ML20086K394 | List: |
| References | |
| AO-74-39, NUDOCS 8401270068 | |
| Download: ML20086K401 (1) | |
Text
g. w a n,-
y, Director
/
Mr. Ja::es P. O'R]' c Energy Co=ission 1
l United States Ato.
l Directorate of Regulatory Operations 631 Park Avenue King of Prussia, Pennsylvania 19406 I
Subject:
Abnoreal Occurrence 24-Hour Notification I
1 Confirming W. T. U11 rich's phone conversation with Mr. Tom Shedlovsky, I
A.E.C. Region 1 Regulatory Operations Office on July 24, 1974.
Reference:
Licenne Number DPR-44, A=endment Number 1 Technical Specification Tabic 3.2.B Report No.:
50-277-74-39 Report Date:
July 24, 1974 Occurrence Date: July 23, 1974 Facility:
Peach Botten Atomic Power Station R. D. 1. Delta, Pennsylvania 17314 Identification of Occurrence:
Static invertcr power supply in the Reactor Core Icolation Cooling System (RCIC) tripped during a start of a recirculation pt=p.
Conditions Prior to Occurrence:
The reactor had scramed from 30% power just prior to this occurrence.
Description of Occurrence:
During a restart of a reactor recirculation pu=p, following a reactor scram, the RCIC inverter failure alarm annunciated in the main control room. The inverter was in:cediately reset.
Designation of Apparent Cause of Occurrence:
The cause of the trippings of the ntatic inverter has not been found.
It is believed that the inverter trips due to a D.C. bus transient following the start of a large A.C. motor.
Analyais of Occurrence:
The operation of the RCIC nystem was not necessary at the time of the tripping. The reactor led jur.t cera=cd on a turbine trip fres high renctor enter level.
Tecauae of this and the imediate restart of the se QQ inverter this occurrence has ninical safety implications.
cn o 00 Corrective Action:
"O The trippings of the inverters are currently under investigation by h
the Philadelphia Electric Co.pany Engineering and Rescarch Departnent.
Pailure Data:
[
s Three other trippings of the inverter have been reported air A0-50-277-74-14, og A0-50-27 7-74-20 and is0-50-277-74-37.
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