ML19352A077

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Responds to IE Bulletin 77-01, Pneumatic Time Delay Setpoint Drift. Approx 75 Pneumatic Time Delay Relays Employed in Safety Sys.Based on Surveillance Programs, Existing Pneumatic Time Delay Relays Are Acceptable
ML19352A077
Person / Time
Site: Oyster Creek
Issue date: 05/27/1977
From: Ross D
JERSEY CENTRAL POWER & LIGHT CO.
To: James O'Reilly
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
References
IEB-77-01, IEB-77-1, NUDOCS 8103020799
Download: ML19352A077 (1)


Text

r CENTM L FtL.tLS IA(9 Jersey Central Power & Light Company %d MADISON AVENUE AT PUNCH BOWL ROAD e MORRISTOWN.N.J.07960

  • 201-539-6111

.....r.,

[y,*] Pubhc Utahties Corpora $ ort Generat SF Sit e May 27, 1977 Mr. James P. O'Reilly, Director Office of Inspection and Enforcement United States Nuclear Regulatory Commission Region i 631 Park Avenue King of Prussia, Pennsylvania 19406

Dear Mr. O'Reilly:

Subject:

Oyster Creek Nuclear Gei.erating Station Docket No. 50-219 IE Bulletin No. 77-01 The purpose of this letter is to respond to the directives set forth in IE Bulletin No. 77-01 which is concerned with pneumatic time delay relay set point drift. An Investigation into the pneumatic time delay relays at the Oyster Creek Nuclear Station showed that there are approximately 75 such relays employed in the safety systems.

The relay manufacturing companies involved are General Electric (CR-120 time delay series), Agastat (7000 series) and Square-D (Cq-1932-G.2). There are no ITE relays used at Oyster Creek.

It is our belief that the Oyster Creek Survelliance Program which is carried out under specific guidelines from the Technical Specifications provides

(

a satisfactory per! odic test of not only relay operation, but also timing tolerances.

In the past 3 years there have been four reportable occurrences involving time delay relays.

Three of these occurrences involved coil or contact failures.

Only one reportable occurrence involved time delay drift.

Relay TK3 was found to time out in 30 seconds with a set point of 40 seconds +15%

(+6 seconds).

This relay is a Diesel Generator load sequence timeractivating Containment Spray Pump SIC.

The relay was recalibrated and placed back in service, but as directed by PORC, it will be replaced during the 1977 refueling outage.

Also at the request of PORC, a review was made to determine if the type of relay in use was the proper one for the appilcation.

The conclusion reacted was that the relay was properly applied in the system and few relays could exceed the demonstrated reliability of the relays presently used.

Based on our experience of minimal pneumatic time delay relay set point drift problems as determined through our surveillance program, we feel that the existing pneumatic time delay relays are functioning as required.

Yours very truly, CM/

)*

Donald A. Ross, Manager

%f Generating Stations-Nuclear