ML20086F997

AO 75-58:on 750821,setpoint of Torus to Reactor Bldg Vacuum Breaker Exceeded Prescribed Limit.Caused by Setpoint Drift. Differential Pressure Indicating Switch Calibr & Setpoint Check Found Repeatable

ML20086F997
Person / Time
Site:	Peach Bottom
Issue date:	08/29/1975
From:	Meyer R PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC
To:	Boyd R Office of Nuclear Reactor Regulation
Shared Package
ML20086G000	List: ML20086F997 ML20086G002
References
AO-75-58, NUDOCS 8401090776
Download: ML20086F997 (2)

Text

e e

,. ,, p r

^

s ( ) i x.s As*

e PHILADELPHI A ELECTRIC COMPANY 2301 MARKET STREET PHILADELPHIA. PA.19101 f 2151041-40o0 August 29, 1975 Mr. Roger S. Boyd, Acting Di rector Division of Reactor Licensing ,

Office of Nuclear Reactor Regulations s' United States Nuclear Regulatory Conunission Washington, D.C. 20555

Subject:

Abnormal Occurrence The following occurrence was reported to Mr. Wal t Baunack, Region 1, Of fice of Inspection and Ent;orcement, Uni ted States Nucicar Regulatory Cormiission on August 22, 1975. Wri tten notification was made to Mr. James P. O'Reilly, Of fice of Inspectic, and Enforcement, Region 1, United States Nuc1 car Regulatory Commis:, ion on August 22, 1975. In accordance with Section 6.7.2.A of the Technical Speci fi-cations, Appendix A of DPR-44 for Unit 2 Peach Bottom Atomic Power S ta ti on, the following report is being submi tted to the Directorate of Reactor Licensing as an Abrormal Occurrence.

Reference:

License Ndmber DPR-44 Technic 61 Speci fication

Reference:

4.7.A.3.2

_ Report No.: 50-277-75-58 Report Date: August 29, 1975 Occurrence Date: August 21, 1975 Facility: Peach Bottem Atomic Power Station R.D. #1, Del ta, Pennsylvania 17314 Identification of Occurrence:

Torus to Reactor Building Vacuum Breaker - setpoint shif t.

Condi tions Prior to Occurrence:

Unit 2 was operating at 90% power.

Description of Occurrence:

During the performance of a routine surveillance test, it was noted that the setpoint of one of the torus to reactor building vacuum breakers ex: ceded i ts prescribed limi t of 0.5 psid by 0.02 psid.

Designation of Apparent' Cause of Occi:rrence:

Setpoint drif t. -

8401090776 750829 ' 3310

PDR ADOCK 05000277 S PDR ' '

Y COPY SENT REGION' 2

-.m Mr. Roger S. Boyd C

50-277-75-58 August 29, 1975 Page 2 1

Analysis of Occurrence:

The safety implications of this occurrence are minimal, since the observed setpoint shif t was 0.02 psid and the torus is designed for a negative pressure of 2.0 psid. In addi tion, the other vacuum breaker tested satisfactori ty.

Corrective Action:

The DPIS was calibrated and the setpoint check was repeatable.

Failure Data:

None previous.

Very truly yours,

,',3()thO O R. D. Meyer General Superintendent Generation Division cc: Mr. James P. O'Reilly, Director, Region i Office of Inspection and Enforcement United States Nuclear Regulatory Commission .

631 Park Avenue King of Prussia, PA 19406 I

i l

-- . ,, # .v-,.