PNO-I-89-036, on 890519,reactor High Level Water Feed Pump Tripped.Caused by Shifting of Feedwater Level Control Sys by Reactor Operator from Single Element to Three Element Control.Water Level Recovered & Isolations Reset

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PNO-I-89-036:on 890519,reactor High Level Water Feed Pump Tripped.Caused by Shifting of Feedwater Level Control Sys by Reactor Operator from Single Element to Three Element Control.Water Level Recovered & Isolations Reset
ML20247F963
Person / Time
Site: Peach Bottom  Constellation icon.png
Issue date: 05/19/1989
From: Johnson T, Wenzinger E
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
To:
References
PNO-I-89-036, PNO-I-89-36, NUDOCS 8905300239
Download: ML20247F963 (1)


- _ _ _ _ _ _ _ - _ _ _

DCS No: 50277/278

. Date: May 19, 1989

. PRELIMINARY' NOTIFICATION OF EVENT OR UNUSUAL' OCCURRENCE--PNO-I-89-3f; This preliminary notification constitutes EARLY notice of events of POSSIBLE safety i 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: '

Philadelphia Electric Co. Notification of Unusual Event Peach Bottom Atomic Power Station Alert Philadelphia, Pennsylvania Site Area Emergency DNs 50-277/278 General Emergency X Not Applicable

Subject:

PEACH BOTTOM UNIT 2 SCRAM Peach Bottom Unit 2 auto scrammed from about 20% power at 7:22 a.m. on May 19, 1989.

The scram occurred when the reactor operator was shifting feedwater level control system from single element to three element control. This action caused the operating reactor feed pump to increase speed. The increased feed water flow resulted in a

, reactor high level water trip of the feed pump at plus 45 inches. Reactor level then

' decreased to the automatic scram and containment isolation setpoint of 0 inches.

Before .a feed pump could be returned to service, the water level continued to decrease to about minus 45 inches. The alternate rod insertion system actuated and both reactor recirculation pumps tripped. The high p essure coolant injection and reactor core isolation cooling systems did not automatically initiate. These safety systems all actuate at a reactor level of minus 48 inches; however, the logic uses different analog trip devices. The licensee recovered water level with the feed pump, reset the scram and containment isolations, and made an ENS call at 8:16 a.m. The licensee is

' investigating the root cause of the scram and reviewing the safety system initiation logic and set points. The Unit is currently in hot shutdown. The NRC restart staff

-continues to provide 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> coverage of licensee activities. The day shift NRC l inspector was in the control room at the time of the scram.

The Commonwealth of Pennsylvania and State of Maryland have been informed.

CONTACT: T. Johnson E. Wenzinger 717-456-7614 346-5225 DISTRIBUTION:

OSFN MNBB H-St. NL Mail: ADM:DMB Chairman Zech AE0D ACRS lies DOT:Trans only Comm. Roberts ARM POR Comm. Carr OGC NRC Ops Ctr Comm. Rogers Comm. Curtiss INP0----

SECY NMSS NSAC----

CA NRR 0GC OIA Regional Offices GPA 01 RI Resident Office PA SLITP EDO DE Licensee:

(Reactor Licensees)

{

Region I Form 83 (Rev. April 1988) '

i e905300239 890519 036 PDC h-I g c -_ __ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _