PNO-I-88-115, on 881101,reactor Scrammed from Full Power Due to Main Turbine Trip.Caused by Loss of Electrical Field on Main Generator.Reactor Stabilized in Shutdown Condition & Entered Into 5-day Outage,Including Deinerting of Drywell

PNO-I-88-115:on 881101,reactor Scrammed from Full Power Due to Main Turbine Trip.Caused by Loss of Electrical Field on Main Generator.Reactor Stabilized in Shutdown Condition & Entered Into 5-day Outage,Including Deinerting of Drywell

ML20195D975
Person / Time
Site:	Hope Creek
Issue date:	11/02/1988
From:	Meyer G, Swetland P NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
To:
References
PNO-I-88-115, NUDOCS 8811070207
Download: ML20195D975 (2)

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, DCS No: 50354881102 Date: November 2, 1988 PRELIMINARY NOTIFICATION OF EVENT OR U; USUAL OCCURRENCE--PNO-I-88-115 This preliminary notification constitutes EARLY notice of events of POSSIBLE safety or public interest significance. The information is as initially received without verification or evaluation, and is basically all that is known by the Region I staf f on this date.

Facility: Licensee Emergency Classification:

Public Service Electric & Gas Co. X Notification of Unusual Event Hope Creek Alert Hancocks Bridge, New Jersey Site Area Emergency Docket No. 50-354 General Emergency Not Applicable Subje-t: SHUTDOWN EXPECTED TO EXCEED TWO DAYS On November 1 at 10:45 a.m., the Hope Creek reactor scrammed from full power due a main turbine trip, which was caused by a loss of electrical field on the main generator. Due to tha pressure spike created by the turbine stop valves closing and the automatic tripping of the three feedwater pumps, the reactor vessel water level decreased and the High Pressure Coelant Injection (HPCI) System automatically initiated as expected to inject water into the reactor and restore water level. One safety relief valve (SRV) automatically actuated electrically to control the pressure spike.

Following restoratica of vessel level and recovery of a feedwater pump, the control room operators terminated the HPCI injection. The reactor was stabiliz2d in a shutdown condition with reactor pressure and water level within normal ranges.

PSE&G evaluation found that the loss of the generator field resulted from arcing within the exciter collector, a brush / ring assembly attached to the end of the generator shaft and used to apply a DC electrical field onto the exciter. Due to lack of availability of replacement parts, PSE&G decided to enter a 5 day outage, includir,g deinerting of the drywell.

Ba3ed on the injection of the HPCI System, an Unusual Event was declared and terminated at 10:55 a.m. on November 1. Notifications of the Unusual Event were made to local, state, and federal authorities.

The resident inspectors will follow the licensee's corrective actions. This PN is issued for information only.

The State of New Jersey has been informed.

CONTACT: G. Meyer P. Swetland 609-935-5151 346-5114 b..)OJ 8911070207 001102 3-PDR I&E FNO-I-88-115 PNU 0\ [OC Q,) jl i

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, OCS No: 50354881102 Y Date: November 2, 1988 PRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE--PNO-I-88-115 This preliminary notification constitutes EARLY notice 9f events of POSSIBLE safety or public interest significance. The information is as initially received without verification or evaluation, and is basically all that is known by the Region I staff on this date.

Facility: Licensee Emergency Classification:

Public Service Electric & Gas Co. X Notification of Unusual Event Hope Creek Alert Hancocks Bridge, New Jersey Site Area Emergency Docket No. 50-354 General Emergency Na Applicable

Subject:

SHUTDOWN EXPECTED TO EXCZED TWO DAYS On November 1 at 10:45 a.m., the Hope Creek reactor scrammed from full power due a main turbine trip, which was caused by a loss ofgqlectrical field on the main generator. Duetothepressurespikecreatedb(lUrbinestopvalvesclosingandthe X' automatic tripping of the three feedwater pumps, the reactor vessel water level decreased and the jiigh Pressure Coolarit Injection (HPCI) System automatically initiated /Oirije~ct water into the reactor and restore water level. One safety relief X valve (SRV) automatically actuated electrically to control the pressure spike.

Following restoration of vessel level and recovery of a feedwater pump, the control room operators terminated the HECI injection. The reactor was stabilized in a shutdown condition with reactor pressure and water level within normal ranges.

PSE&G evaluation found that the loss of the generator field resulted from arcing within the exciter collector, a brush / ring assembly attached to the end of the generator shaf t and used to apply a DC electrical field onto the exciter. Due to lack of availability of replacement parts, PSE&G de:ided to enter a 5 day outage, including deinerting of the drywell.

Based on the injectien of the HPCI System, an Unusual Event was declared and terminated at 10:55 a.m. on November 1. Notifications of ths Jnusual Event were made to local, state, and federal authorities.

The resident inspectors will follow the licensee's corrective actions. This PN is issued for information only.

The State of New Jersey has been informed.

CONTACT: G. Meyer P. Swetland p, ,,

609-935-5151 346-5114 g' /

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