ML19242D035

Nonroutine Environ Operating Rept 50-219/79-01 on 790725-26:discrepancy Found Between Condenser Discharge Temp Recorder & Output of Microprocessor Used to Provide Thermal Logging & Alarms.Microprocessor Reprogrammed

ML19242D035
Person / Time
Site:	Oyster Creek
Issue date:	08/07/1979
From:	JERSEY CENTRAL POWER & LIGHT CO.
To:
Shared Package
ML19242D030	List: ML19242D029 ML19242D035
References
NUDOCS 7908140391
Download: ML19242D035 (2)

Text

.

Jersey Central Power & Light Company 7i N , Gj" ~ ],4 ' h

" M -

/ "y J-' Madison Avenue at Punch Bowl Road Morristown, New Jersey 07960 (201)455-8200 OYSTER CREEK NUCLEAR GENERATING STATi d Forked River, New Jersey 08731 Nonroutine Environmental Operating Report No. 50-219/79-1 Report Date August 7, 1979 Occurrence Date July 25, 1979 to July 26, 1979 Time of Occurrence 20:15 to 03:45 Identification of Occurrence Violation of a limiting condition for operation as per Technical Specifications, Appendix "B", paragraph 2.1.3.1. This event is considered to be a nonroutine environmental operating report as defined in the Technical Specifications, Appendix "B", paragraph 5.6.2.

Conditions Prior to Occurrence The plant was operating at steady state power.

Dilution l' ump Flow: C.20 x 105 gpm Circulating Pump Flow: 4.60 x 105 gpm Power: Reactor 1900 MWt Electrical 640 MWe Description of Occurrence At approximately 0900 hours0.0104 days <br />0.25 hours <br />0.00149 weeks <br />3.4245e-4 months <br /> on July 26, 1979, a aiscrepancy was discovered between the condenser discharge temperature recorder and the output of the microprocessor used to provide logging and alarm of the thermal data.

Upon investigation, it was determined that the processor was reading 2.6*F.

lower than the recorder and since Operations personnel were using the processor output to comply with the Environmental Technical Specifications, the limit for the condenser discharge temperature was exceeded. This limit of 106*F.

was exceeded between 2015 hours0.0233 days <br />0.56 hours <br />0.00333 weeks <br />7.667075e-4 months <br /> on July 25, 1979, and 0345 hours0.00399 days <br />0.0958 hours <br />5.704365e-4 weeks <br />1.312725e-4 months <br /> on July 26, 1979. A peak (15 minute average) temperature of 106.7*F. occurred between 2330 hours0.027 days <br />0.647 hours <br />0.00385 weeks <br />8.86565e-4 months <br /> and 2345 hours0.0271 days <br />0.651 hours <br />0.00388 weeks <br />8.922725e-4 months <br /> on July 25, 1979

(;; 3 (;33 '008140 3 7 /

yo Jersey Central Power & Light Company is a Member of the General Pubhc Utities System

Nonroutine Enviror antal Operating Report No. 50-219/79-1 Page 2 August 7, 1979 Apparent Cause of Occurrence A Hewlett Packard mini processor is used to monitor the outputs of the environs temperature sensors. Calibration of the condenser discharge temperature monitoring channel indicated that the millivolt to current component of the channel was providing a " low" output. Consequently, the mini processor which reads the mill! volt / current component also displayed a " low" output. Upon obtaining the results of the calibration (July 26, 1979) and reviewing the output of the mini processor for the period of discussion, it was determined that the actual discharge temperature did exceed 106.0 F.

Analysis of Occurrence During this occurrence, no unusual environmental effects were observed. The Technical Specifications allow for exceeding 106*F. In the event of a need for emergency power. Under an emergency need for power, the Technical Specifications allow a discharge temperature of 110 F. It should be noted that an emergency need for power did exist at the time.

Corrective Action immediate corrective action was to notify Operations personnel that the mini processor output of 103.7*F. corresponds to a discharge temperature of 106.0*F.

Correction factors were subsequently programmed into the processor to achieve the required accuracy.

Failure Data N/A

'd I

._