ML20086E696

From kanterella
Jump to navigation Jump to search
AO 74-05:on 740304,LPCI Valve V10-25A Failed to Open When Control Switch Placed in Open Position.Caused by Tripped Motor Breaker & Unusually Warm Motor.Motor Replaced
ML20086E696
Person / Time
Site: Vermont Yankee File:NorthStar Vermont Yankee icon.png
Issue date: 03/05/1974
From: Riley B
VERMONT YANKEE NUCLEAR POWER CORP.
To:
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML20086E684 List:
References
AO-74-05, AO-74-5, VYV-3183, NUDOCS 8312070489
Download: ML20086E696 (1)


Text

_,

O O

VEinioNT YANKEE NUCLEAR power CORPORATION

_y GCVCHTY GCVcN OROVC STRCCT RuTLAND, VI:ltMONT 03701

~

VYV-3183 P.O.DOX 157 VERNON, VCHMONT oS354 March 5, 1974 N,,',,

,\\

United States Ato:: tic Energy Commission i

w.

Directorate of Regulatory Operations, Region I

  • g g\\

631 Park Avenue

-U T)

I lk8 Jgg g Hj 2

King of Prussia, Pennsylvania 19406 T

I

REFERENCE:

Operating License DPR-28 bo a Occ c.cc No. A0-74-05 ND Gentlemen:

f As' defined by Technical Specifications for the Vermont Yankee Nuclear Power Station, Section 6.7.B.1, we are reporting the following Abnormal Occurrence as A0-74-05 and confirming out telephone conversation with your office.

At approximately 2130 on March 4, 1974, while performing routine surveillanc'e testing en the Low Pressure Coolant Injection System (LPCI),

valve V10-25A failed to open when the control switch was placed in the open position.

It was determined that this condition was in violation of Technical Specifications, Section 1.0.A.4 in that it could have prevented the performance of the intended safety function of an engineered safety feature system.

The valve was manually opened immediately and the system injection line upstream normally open valve V10-27A was

~

closed.

Since this valve will open in response to a LPCI automatic initiatiot. signal, the subsystem was considered operable.

The reactor was operating at approximately 78% power at the time of this incident.

~~

Initial investigation revealed that the valve motor was unusually warm and that the motor breaker had tripped.

Subsequent action will determine the cause of the valve probica and replace the valve motor.

Very truly yours, VERMONT YANKEE NUCLEAR POWER CORPORATION f

8312070489 740311 i

PDR ADOCK 05000271 Ar?/

v:2

,.r B.W. Riley jt/

[

7 Plant Superintendent WFC/kbd

}g 9

4 SQPY SIWf REQION-

,