ML19253C333

LER 79-026/03L-0:on 791022,during Turbine First Stage Low Pressure Calibr Procedure Qis 55-1,pressure Switch PS-2-504C Tripped Above Tech Spec Limit.Caused by Instrument Set Point Drift.Pressure Switch Recalibr

ML19253C333
Person / Time
Site:	Quad Cities
Issue date:	11/16/1979
From:	Robert Murray COMMONWEALTH EDISON CO.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
Shared Package
ML19210E143	List: ML19210E142 ML19253C333
References
LER-79-026-03L-03, LER-79-26-3L-3, NJK-79-421, NUDOCS 7911300552
Download: ML19253C333 (1)

Text

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f 0 TT1 I While performino the Turbine First Staae Low Pressure Calibration. orncedure l o 3 l QlS 55-1, pressure switch PS-2-504C was found to trip at 1 psi above the Technical l' o 4 l Specification Table 3.1-3 limit of 400 psi. Redundant pressure switches PS-2-504A, l o 3 B, and D were found to trip within the acceptable limit. Subsequently turbine stop l y o ; ,,. y valve closure, turbine generator load reject, and EHC fluid low pressure scram l o 7 l functions were not affedted by this event. I 10181 1 I 7 8 9 80 DE CODE S BC E COMPONENT CODE SUBC D'E SU E LO_L9J 7 8 l II Al@ l El@

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13 18 19 20 SEQUENTIAL OCCURRENCE REPORT REVISION LER EVENT YEAR REPORT NO. CODE TYPE N O.

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40 di CAUSE DESCRIPTION AND CORRECTIVE ACTIONS h i O The cause of this occurrence is attributed to Instrument set point drift. The correc-l g,j,g tive action taken was to recalibrate pressure switch PS-2-504C to actuate at a turbinel first stage pressure of 389 psi. In addition, instrument cal.ibration records are I g kept and used to closely monitor the components of the reactor protection system. l LLLdJ L l 7 0 9 80 ST S  % POWER OTHER STATUS DIS O RY DISCOVERY DESCRIPTION dl El @ l 4 8 51@l NA l lBl@l Routine Test l ACTIVITY CC I Ei. T AMOUNT OF ACTivlTY LOCATION OF RELEASE i 6 RELEl Zl ASE@D OF RLLEASElZl@ NA l l NA l 7 8 9 to 11 44 45 80

1. ERSONNEL ExPCSLRES

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NAME OF PREPARER PHONE: 309-654-2241 ext. 172 $

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