ML20086J131
| ML20086J131 | |
| Person / Time | |
|---|---|
| Site: | Peach Bottom  |
| Issue date: | 12/26/1974 |
| From: | Cooney M PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC |
| To: | Anthony Giambusso US ATOMIC ENERGY COMMISSION (AEC) |
| Shared Package | |
| ML20086J134 | List: |
| References | |
| AO-74-37, NUDOCS 8401230213 | |
| Download: ML20086J131 (2) | |
Text
{{#Wiki_filter:- - l c a ) PHILADELPHIA ELECTRIC -COM PANY $US 23O1 MARKET STREET .-';, V;. .*.t \\9 PHILADELPHIA. PA.19101 y&n .. l k -{ t y, l '** 84b'O U ( 3 December 26, 1974 , - -< i 1 , ;v i Mr. A. Giambusso Deputy Director of Reactor Operations United States Atomic Energy Commission Directorate of Licensing Washington, D.C. 20545
Dear Mr. Giambusso:
Subject:
Abnormal Occurrence The following' occurrence was reported to Mr. Wal t Baunack, A.E.C. Region 1 Regulatory Operations Of fice on December 16,1974 Written notification was made to Mr. James P. O'Reilly, Region 1 Regulatory Operations Office on December 16, 1974 In accordance with Section 6.7.2.A of the Technical Speci fications, Appendix A of DPR-56 for Unit 3 Peach Bottom Atomic Power Station, the following report is being submitted to the Directorate of Licensing at an Abnormal Occurrence.
Reference:
License Number DPR-56 Technical Speci fication
Reference:
Table 4.2.B Report No.: 50-278-74-37 Report Date: December 26, 1974 Occurrence.Date: December. 16,'1974 Faci li ty: Peach Bottom Atomic-Power Sta tion R.D. //1, Del ta, -Pennsylvania 17314 Identi fication of Occurrer.ce: Failure of a torus high water level swi tch, LS-3-23-91A to ope ra te. This swi tch operates to _syway_p 11PCI suction from the con-densate storage tank to the suppression pool. 1 Im Conditions Prior to Occurrence: Unit 3 at approximately 55% power. p -h. ~ Description-of Occurrence: [ a-During a routine instrument survei llance. test, LS-3-23-91 A - . failed to operate. f 8401230213 741226 DR ADoCK 05000278 S 1 .P _ _ DR =. C O U OIANII'bOIuN " /
'e Il I') Mr. A. Giambusso U L December 26, 1974 Page 2 Designation of Apparent Cause of Occurrence: The switch assembly flapper arm was found to be slightly restricted by the swi tch case. Analysis of Occurrence: LS-3-23-91A and LS-3-23-910 operate independently to swap the HPCI suctior. from the condensate storage tank to the suppressior pool. LS-3-23-91B had just been tested and found to function properly. Because the failure of LS-3-23-91A to operate would not have interfered with the proper operation of the system, the safety implications are minimal. Corrective Action: Since a similar failure had occurred previously and a re-adjustment of the switch mechanism had been performed, it was decided this time to dismantle the float / shunt assembly. The shunt was found to have greater than an inch of excess vertical play. The amount of play was reducea to about one-sixteenth of an inch and the shunt moved higher on the float extension arm to allow adjustment of the switch assembly away f rom the base of the swi tch case. The switch was cycled a number of times using water to lif t the float, and then rechecked using the appropriate instrument surveillance test. Failure Data: A previous failure of this switch was reported as Abnonnal Occurrence Number 50-278-74-25. Very truly yours, l'1 '] j. v Y ll j Bu f M. J. Cooney Asst. Geni. Supt. Generation Division ~ cc: Mr. J. P. O'Reilly Di rector, Region i Uni ted States Atomic Energy Commission 631 Park Avenue King of Prussia, PA 19406 . - -}}