ML20045B238

Special Rept:On 930523,EDG E-2 Declared Inoperable When Engine Lubricating Oil Temp Alarm Annunicated on Low Temp Condition.Caused by Circulating Pump Trip on Thermal Overload.Thermal Overload Assembly Reinstalled

ML20045B238
Person / Time
Site:	Peach Bottom
Issue date:	06/09/1993
From:	Powers K PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
CCN-14082, NUDOCS 9306170008
Download: ML20045B238 (2)

Text

CCN-14082 t

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PHILADELPHIA ELECTRIC COMPANY tr PEACH BOTTOM ATOMIC POWER STATION R. D.1, Box 208 l

g* q yg DELTA, PA 17314

'" p (717) 456-7014 Nna TD **

June 9, 1993 KENi Docket Nos. 50-277 50-278 License Nos. DPR-44 DPR-56 Document Control Desk U. S. Nuclear Regulatory Commission Washington, DC 20555 i

K

SUBJECT:

Peach Bottom Atomic Power Station - Unit 2 & 3 Special Report for a Non Valid Failure of the E-2 Emergency Diesel Generator on 5/23/93

REFERENCE:

Peach Bottom Atomic Power Station Technical Specification (Tech Spec) 4.9.A.1.2.L This Special Report is submitted pursuant to the requirements of Tech Spec 4.9.A.1.2.L l

This Surveillance Requirement requires reporting of all Emergency Diesel Generator (EDG) failures, valid or non valid, within 30 days. This report is required to include the information recommended in Regulatory Position C.3.d of Regulatory Guide (RG) 1.108

" Periodic Testing of Diesel Generator Units as Onsite Electric Power System at Nuclear Power Plants", Revision 1, August 1977.

On 5/23/93 at 1031 hours0.0119 days <br />0.286 hours <br />0.0017 weeks <br />3.922955e-4 months <br />, with Unit 2 at 100% and Unit 3 at approximately 80% power, the E-2 EDG was declared inoperable when the engine lubricating oil temperature alarm r

• LUBE OIL LOW TEMPERATURE" annunciated on a low temperature condition. The associated Alarm Response Card directed the Shift Supervisor to consider the EDG inoperable. This is based on a manufacturer's recommendation that the EDG could not be guaranteed to start within the 10 second criteria specified in the SAR with the low lube i

oil temperatures. In this condition, the E-2 EDG would have started but could have exceeded the 10 second criteria.

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Troubleshooting was immediately conducted to determine the cause of the low oil temperature condition. It was determined that the cause of the occurrence was that the E-2 EDG Standby Lube Oil Circulating Pump had tripped on thermal overloads and could not be reset. The existing thermal overload heaters were previously determined to be incorrectly sized under a Non Conformance Report (NCR).

The NCR has been dispositioned to replace the heaters with higher rated units.

The thermal overload assembly was immediately removed, cleaned, and reinstalled so that the trip could be reset and the pump returned to service. At 1228 hours0.0142 days <br />0.341 hours <br />0.00203 weeks <br />4.67254e-4 months <br />, the E-2 EDG lube oil temperature was restored and the EDG was considered operable. On 5/25/93, the thermal overload heaters on the E-2 EDG Standby Lube Oil Circulating Pump were replaced with higher rated units as previously dispositioned in the NCR. The E-4 EDG Standby Lube Oil Circulating Pump thermal overload heaters were previously

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replaced with the correct sized units on 5/12/93. Planned corrective actions were in place prior to this occurrence and the other EDG thermal overload heaters will be replaced based on parts availability.

The E-2 EDG failure was classified as a non valid failure using the guidance of RG 1.108, Revision 1,1977. Because this occurrence was classified as a non valid failure, the

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current surveillance testing interval will remain at once per 31 days which is in conformance with RG 1.108, Revision 1, Section C.2.d.

The E-2 EDG was available for the duration of the event but was considered administratively inoperable for 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> and 57 minutes. Although the EDG was considered inoperable due to the failure of the Lube Oil Circulating Pump, the E-2 EDG would have started if an initiation signal was present. However, it r..ay have taken more than 10 seconds to start the EDG and achieve rated speed and voltage as described in the SAR.

In addition, the remaining EDGs were operable and would have provided adequate AC power to safety related loads in the event of an actual loss of offsite power.

If you have any questions or require additional information, please do not hesitate to contact us.

Sincerely, cc:

R. A. Burricelli, Public Service Electric & Gas i

W. P. Dornsife, Commonwealth of Pennsylvania T. T. Martin, US NRC, Region i R.1. McLean, State of Maryland B.

Norris, US NRC Senior Resident inspector H. C. Schwemm, Atlantic Electric C. D. Schaefer, Delmarva Power

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