ML20086J372
| ML20086J372 | |
| Person / Time | |
|---|---|
| Site: | Peach Bottom  |
| Issue date: | 10/14/1974 |
| From: | Cooney M PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC |
| To: | Anthony Giambusso US ATOMIC ENERGY COMMISSION (AEC) |
| Shared Package | |
| ML20086J376 | List: |
| References | |
| AO-74-12, NUDOCS 8401230616 | |
| Download: ML20086J372 (2) | |
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PHILADELPHIA ELECTRIC COMPANY
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October 14, 1974 Mr. A. Giambusso Deputy Director of Reactor Projects United States Atomic Energy Cormiission Directorate of Licensing Washington, DC 20545
Dear Mr. Giambusso:
Subject:
Abnormal Occurrence The following occurrence was reported to Mr. Walt Bounack, A.E.C. Region 1 Regulatory Operations Office on October 4,1974.
i Written notification was made to Mr. James P. O'Reilly, Region I Regu-3 latory Operations Office on October 7,1974.
In accordance with Section 6.7.2.A of the Technical Specifications, Appendix A of OPR-56 for Unit 3 Peach Bottom Atomic Power Station, the following report is being submitted to the Directorate of Licensing as an Abnormal Occurrence:
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Reference:
License Number DPR-56 Technical Specification Reference Table 3 2.B j
Report No.:
50-278-74-12 i
Report Date:
October 14, 1974 e
[d Occurrence Date:
October 4,1974 Facility:
Peach Bottom Atomic Power Station R.D. 1, Delta, Pennsylvania 17314 Identification of Occurrence:
1 Setpoint drif t on the RCIC turbine high reactor water level k
in a direction less conservative than specified in the Technical sensor
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h Speci ficati ons.
4 Conditions Prior to Occurrence:
n Unit 3 Start-Up, reactor critical, reactor pressure less than k
200 ps i.
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Mr. A. Giambusso p
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Description of Occurrence:
During.a routine instrument calibration surveillance test, the setpoint of one of the RCIC turbine high reactor water level sensors, LIS-3-2-3-101A, was found to have drifted outside the limit called for in the Technical Specifications. The prescribed setpoint for this de-vice is145". The device was found to trip at 45.1".
Designation of Apparent Cause of Occurrence:
The wheel on the cam follower was found to be binding, requir-ing greater motion on the cam to trip the switch.
Analysis of Occurrence:
Since the setpoint was minor, and would not have prevented the sensor from providing a high level signal to the RCIC turbine trip logic, this occurrence has minimal safety implications.
Corrective Action:
The cam follower assembly was replaced; setpoint adjusted and checked for repeatability; and the instrument functionally checked per the applicable surveillance test prior to returning it to service.
L Failure Data:
These dif ferential pressure switches have required frequent recalibrations to correct setpoint shifts.
Since the start-up of Unit 2, setpoint shif ts cn the instruments in this service have required re-calibration on 24 occasions.
Shif ts to values in excess of Technical er Specification limits occurred six tines including this occurrence. - Most of these deviations were only slightly beyond the' required setpoints and did not cons.titute a safety hazard.
Very truly yours,
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. J. Cooney s
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't Gen't Superintendent d
Generation Division cc:
Mr. J. P. O'Reilly Director, Region 1 United States Atomic Energy ' Commission King of Prussia, PA
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