PNO-III-86-112, on 861009,problem Occurred W/Rod Sequence Control Sys,Hindering Normal Manual Insertion of Control Rods.Caused by Low Voltage in Normal Power Supply.Evaluation of Problem Underway
| ML20211B263 | |
| Person / Time | |
|---|---|
| Site: | Fermi  |
| Issue date: | 10/10/1986 |
| From: | Guldemond W, Wright G NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | |
| References | |
| PNO-III-86-112, NUDOCS 8610170167 | |
| Download: ML20211B263 (1) | |
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- PRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE--PNO-III-86-112 Date October 10, 1986 06 This preliminary notification constitutes EARLY notice of events of POSSIBLE safety cr public interest significance. The information is as initially received without verification or evaluation, and is basically all that is known by the Region III staff on this date.
Facility:
Detroit Edison Company Licensee Emergency Classification:
Fermi 2 huclear Power Plant Notification of an Unusual Event Newport, MI 48166 Alert Site Area-Emergency Docket No. 50-341 General Emergency X Not Applicable
Subject:
SHUTDOWN TO REPAIR POWER SUPPLY UNIT At 9:41 a.m. (EDT) on October 9,1986, a modular power unit automatically shifted to its alternate power supply because of low voltage in the nomal power supply. The power transfer resulted in the loss of multiple non safety-related instrument systems in the control room, a partial loss of station air system, and a turbine trip. The modular power unit is one of four instrument power supplies for balance-of-plant instrumentation.
The licensee decided to shut the unit down for the power supply repairs. During the shutdown a problem occurred with the rod sequence control system, hindering ths normal manual insertion of control rods. Reactor ' operators then manually scramed the unit at 9:09 p.m. (EDT),
October 9, 1986.
The shutdown is expected to last at least until October 12, 1986. During the outage, the licensee will evaluate the problems with the rod sequence control system and the modular pow:r unit.
The resident inspections and the Region III (Chicago) restart team will monitor the licensee's-activities.
The State of Michigan will be informed.
The licensee notified the Headquarters Duty Officer of the power supply problem at 1:08 p.m.
(EDT), October 9,1986. This information is current as of 9 a.m. (EDT), October 10, 1986.
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/ sg CONTACT: Gf C. Wright Td on FTS 388-5695 FTS 388-5574 DISTRIBUTION:
H. St.
ED0 NRR E/W Willste Mail: ADM:DMB Chairman.Zech PA IE NMSS D0T:Trans only Com. Roberts ELD OIA RES Com. Asselstine AE0D Comm. Bernthal Com. Carr SP 2 M Regional Offices ACRS SECY INP0 2:3)
NSAC A:$5,_
CA RIII Resident Office PDR Licensee:
S,51 (Corp. Office - Reactor Lic. Only)
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~~~~510170167 861010 Region III O;I B
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-I B6-122.PDR I?
Rev. November 1985
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