ML20093H690
| ML20093H690 | |
| Person / Time | |
|---|---|
| Site: | Oyster Creek |
| Issue date: | 07/18/1984 |
| From: | Fiedler P GENERAL PUBLIC UTILITIES CORP. |
| To: | Deyoung R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE) |
| References | |
| IEB-84-02, IEB-84-2, NUDOCS 8407250240 | |
| Download: ML20093H690 (3) | |
Text
{
l l
GPU Nuclear Corporation
- Nuclear
- e"t:388 Forked River, New Jersey 08731-0388 609 971-4000 Writer's Direct Dial Number:
Mr. Richard DeYoung, Director Office of Inspection and Enforcement U.S. Nuclear Regulatory Commission Washington, DC 20555
Subject:
Oyster Creek Nuclear Generating Station Docket No. 50-219 IE Bulletin 84-02
Dear Mr. DeYoung:
The purpose of this letter is to respond to the directives set forth in IE Bulletin 84-02 which is concerned with f ailure, replacement and surveillance of G.E. HFA relays being used in class IE safety systems. Our response to the specified action items in the subject bulletin are in an attachment to this letter.
If ycu have any questions, please call me or the Oyster Creek Licensing Manager at (609)971-4643.
Very truly yours, A
die Vice President and Director Oyster Creek PBF/DGH/ dam Attschment cc: Dr. Thomas E. Murley, Administrator Region I U.S. Nuclear Regulatory Commission 631 Park Avenue King of Prussia, PA 19406 NRC Resident Inspector Oyster Creek Nuclear Generating Station Forked River, NJ 08731 8407250240 84071g gDRADOCK 05000219 PDR 1 \\
GPU Nuclear Corporation is a subsidiary of the General Public Utilities Corporation
~.
3 y
ATTACHMENT
~
Item No. la-Develop plans.and schedule for replacing (1) nylon or Lexan coil spool-type HFA relays used in normally energized safety related applications and :(2) nylon coil spool-type HFA relays used in normally de-energized safety related applications. The replacement relays and any replacement made in the future should meet the requirements of the applicable IEEE standards. The replacement. program for energized and de-energized relays should be performed
.on a best effort" basis during plant outages of sufficient duration. The entire ' replacement' program should be completed within two years from the date Tof this bulletin.
. The replacement schedule should consider the following recommended
{ priority:
Nylon or Lexan normally energized in the reactor trip system.
Nylon or Lexan normally-energized in other safety related applications.
, Nylon normally de-energized in the reactor trip system.
Nylon normally de-energized in other safety related applications i
^ Response'to Item la' 1 Prior to plant startup from our present refueling outage:
- 1) All Lexan and nylon RFA relays in normally energized Reactor Protection Trip Systems will be' replaced;
- 2) ~ All Lexan and nylon HFA relays in normally de-energized Reactor Protection. Trip Systems will be replaced;
- 3) All nylon HFA relays in normally energized Reactor Trip Systems will be replaced;
- 4) All Lexan HFA relays in other normally energized safety related
. applications will be replaced;
- 5). All Lexan RFA relays in other-normally de-energized safety related applications will-be replaced; All nylon HFA relays. on both normally energized and normally de-energized safety related systems will be replaced during our next scheduled refueling cutage.
Item No. lb-During the period before relay replacement, develop and implement surveillance plans that include:
1 of 2 i
_. _. ~...... -., _,
_....,,...,,.. ~., _.., _.., _ _ _ _. _ _,,... _. _ _. _., -.
.p'
- 1) M:nthly functional tests of all Rtactor Trip System normally energized relays that verify relay contacts change state when the relay coil is de-ene rgized.
- 2) Visual inspections should be accomplished in conjunction with the monthly functional test and should verify that relay coils are not deteriorating (e.g., inspect coil bobbins for visible cracks or melting and confirm cleanliness of relay' pole pieces).
Response to Item No. lb
- 1) As.of this date all Reactor Trip System normally energized relays have been replaced, therefore, no additional testing as stated in this bulletin
. will be performed for the R: actor Protection Trip System.
' 2) Oyster Creek is presently conducting visual inspections of the normally energized HFA relays in other safety related systems on a monthly basis.
These inspections will continue until the relays are replaced.
Item No. Ic Provide a basis for continuing operation for the period of time until the normally energized relays are replaced. This basis should include a
- discussion of those measures addressed in items la and lb and eny other preventive and/or corrective measures taken or planned.
' Response to Item No. Ic Normal plant operation'during'this period should not be affected for the
--following reasons:
- The only relays requested to be replaced remaining at the plant in normally energized safety related applications are of the nylon type.
No related failures other than the random end of life failures have been recorded for nylon coil RFA relays. These were occurring on normally energized relays only.
~With a visual inspection program in effect, the plant will be able to detect any cracks or signs of internal heating of'the coil bobbins. This, ocombined with confirming cleanliness of the relay pole pieces will allow us to replace a relay before a failure' occurs. Our experience shows all failures were preceded by : humming and buzzing.
'None of the affected relays are in the Reactor Trip Systems. 'It is not likely to have failures in two systems at one time, and redundant systems are i available =forf each safety related function.
If a failure occurred,it would not affect the plant shutdown capability.
~
2 of 2 i
_.