ML19320D454

Ro:On 800711,Unit 1 LPCI Inverter Tripped & Unit 2 4-kV Bus 2F Supply Breaker & HPCI Tripped.Supply Breaker Trip Caused by Jumper Missing from Neutral Leg.Motor Valve on HPCI Replaced Making It Operable.Events Submitted Per Ieb 80-17

ML19320D454
Person / Time
Site:	Hatch
Issue date:	07/14/1980
From:	Manry M GEORGIA POWER CO.
To:
References
IEB-80-17, PM-80-709, NUDOCS 8007210384
Download: ML19320D454 (2)

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ma Edwin I.Hetch Nuclear Plant Geog.$i Power iln!se viln 1n e,*n f e: :.y' icit t July 14, 1980 PM-80-709 PLANT E. I. HATCll '

IES 80-1/ Prompt Reporting Confirmation United States Nuclear Regulatory Commission Office of Inspection and Enforcement Region II Suite 3100 101 Marietta Street Atlanta, Georgia 30303 ATTENTION: Mr. James P. O'Reilly Below is a summary of events for bnits 1 and 2 of Plant Hatch that ware reported per IEB 80-17, part 6a. These events were discussed with your Mr. Nolan on July 12, 1980, at 12:00 PM EDT.

Unit 1 On July 11, 1980, the LPCI inverter R44-S003 was declared inoperabic twice due to its having tripped at the following times: 1) From 1220 CDT to 1315,CDT and 2) From 2045 CDT to 2140 CDT. In each case, the inverter was inoperative only during the time period when it was tripped. Loss of this inverter removes control power for valves Ell-F007B, and Ell-F015B, rendering the "B" loop of RHR inoperative.

Unit 2 At 0705 CDT on July 11, 1980, the normal supply breaker to 4KV bus 2F tripped, placing the bus on alternate feed. At 1200 CDT, the citernate supply breaker tripped leaving bus 2F de-energized. The RilR following safety related equipment was rendered inoperative:

CRD pump 2B, pumps 2C and 2D, RHRSW pump 2C, PSW pumps 2C and 2D, investigation for Standby PSW pump 2P41-C002. After a preliminary At -

the problem was conducted, the bus was re-energized at 1250 CDT.

1500, while investigating the cause for the breaker trips, a jumper was found to be missing in the neutral leg of the protective relay current loop. The absence of the jumper had caused a false current value to be present in the neutral leg. i l

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At 0455 on 7-11-80, IIP C I was being used to control reactor pressure following a scram. The motor to valve 2E41-F006 burned up while in use, rendering IIP CI inoperative. The motor from valve 2E41-F007 was removed and installed on 2E41-F006. Valve 2E41-F007 was locked in the open position. At 0030 on July -1 2 , 1980, HNP-2-3302 (MOV operability procedure) was sucessfully completed for valve 2E41-F006. At 0330, HPCI was declared operable.

UhtM'/ 5 M. Itanry ,

Plant 11a n er IILS / hh xc: R. J. Kelly W. A. Widner ,

C. L. Coggin -

R. D. Baker l

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