ML20095G881
| ML20095G881 | |
| Person / Time | |
|---|---|
| Site: | Hatch  |
| Issue date: | 07/13/1984 |
| From: | Gucwa L GEORGIA POWER CO. |
| To: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| IEB-84-02, IEB-84-2, NED-84-352, NUDOCS 8408280239 | |
| Download: ML20095G881 (4) | |
Text
Georgia Power Company h
_y
, :o 333 Piedmont Avenue s-Atlanta, Georgia 30308.
TeLW 404 52&6526 Mailing Address:
. Post Offce Box 4545 Atlanta. Georgia 30302
", n. 4 3 Georgia Power J-Mad. age Nuclear Engoeering and Chef Nuclear Eng!ncer gyp.g4 33g July 13, 1984 U. S. Nuclear Regulatory Commission
REFERENCE:
Office of Inspection and Enforcerent ~
RII: JF0 Region II - Suite 2900 50-321/50-366 101 Marietta Street,-hW I6E Eulletin Atlanta, Georgia 30323 84-02
-ATTENTION: Mr. James P. O'Reilly GENTIREN:
We following informaticn is provided as requested in I 6 E Bulletin 84-02, which was issued March 12, 1984.
Summary of Eulletin subject (s):
The purpose of ISE Eulletin 84-02 is to request that Licensees and Construction Fermit holders provide the NRC with their plans, including schedules, for replacing HFA relays in the Reactor-Protection System and other safety related systems.
In addition, licensees are asked to provide information concerning plans to upgrade
. surveillance and to justify continued operation in the interim.
Actions in Eulletin for all holders of Operating 1.icenses:
"Since GE asserts that the new Century Series HFA relay has been successfully tested to the environmental and seismic requirements specified in the IEEE-323-1974 and IEEE-344-1975 Standards, this relay, or cne of equal qualification, may be an acceptable replacement for - Lexan/ Nylon HFA relays now in service.at many nuclear power plants. However, the licensee is responsible for determining that all safety - grade equipment in the plant, including relays, is qualified for its intended service.
%at is, the licensee must establish and document that the service life and reliability of the relay is acceptable,..and that-the relays have been qualified for the environmental and seismic conditions that each device may encounter at its installed location in the plant."
-1.
Plants in Operation Item a.
" Develop plans and schedules 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.
%e replacement relays and any replacements 8408280239 840713' PDR ADOCK 050003gt
f
, Georgia Powerd U. S. Nuclear-Regulatory Commission Office of Inspection and Ehforcement Region Suite 2900-July 13, 1984 Fage Two Item a. (Continued):
made in the future should meet the requirements of the applicable IEEE -standards.
%e replacement program for energized and de-energized relays should be performed on ~a "best efforts" basis -during plant outages of sufficient duration.
%e entire replacement program should be completed within two years from the date of this bulletin. (March 12, 1986)
%e replacement schedule should consider the following recommended priority:
hylon or Lexan nomally 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."
Response to Item a:
Replacement 'of the existing Flant Hatch HFA relays is scheduled for the Unit 1,1984 refueling outage (RPS relays only) and the Units 1 and :2, 1985 refueling outages.
He priority will be to replace normally energized HFA relay coils
- first, with replacement of de-energized coils following.
Replacement will be with GE Century Series HFA relays, or equivalent, which have been fully qualified for usage at Plant Hatch.
Item b.
"During the period before relay replacement, develop ard implement surveillance plans that include:
'(1) Monthly functional tests of all reactor trip system normally energized relays that verify relay contacts change state when the relay coil is de-energized; (2) Visual inspections of all safety-related normally energized relays as - soon as practical upon receipt of this bulletin.
%ereafter, similar inspections should be accomplished in conjuntion with the monthly functional test. Dese visual inspections shculd verify that relay coils are not deteriorating (e.g.,
inspect coil bobbins for visible cracks or melting), and should confirm cleanliness of the relay pole pieces."
- 700775
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o G'corgia Power 1
- U. S.' Nuclear Regulatory Commission Office of -Inspection and Fmforcement '
Region-II - Suite 2900 July 13,1984 Fage Three Response to Item b:
(1) : All reactor trip system normally energized relays are currently tested at least once per month using the following procedurer:
High Reactor Fressure -Instrumentation a.
HNP-1/2-3001 FT6C.
-b.
HNP-1/2-3002 High Drywell Pressure Instrument (RFS)
FT6C.
c.
HNP-1/2-3003 - Reactor Water level (RPS) FT6C.
d.
HNP-1/2-3004 - High Scram Discharge Volume level Float Switch Instrument FT6C.
e.
HNP-1/2-3005 - Main Steamline High Rediation Instrument FT6C.-
f.
HNP-1/2-3006 - MSIV Closure Instrument Ebnctional Test.
Turbine Stop Valve Fast Closure g.
IEP-1/2-3007 Instrument FTEC.
h.,
IINP-1/2-3008 - Turbine Stop Valve Instrument Function Test.
i.
HNP-1/2-3052 - IRM Instrument Functional Test.
j.
IEP-1/2-3054 - AFRM Instrument FTEC.-
k.
HNP-1/2-3013 - Reactor Manual Scram Fbnctional Test.
(2)
A visual inspection of. the end flange of coil bobbins / spools of all safety-related normally energized relays on both units was performed by the cognizant System Fngineer on June 13, 1984, he to verify that the relay coils were not deteriorating.
T inspection revealed no major visible cracks or signs of melting.
Also, cleanliness around the relay pole pieces was confirmed.
A procedure for performing visual inspections on both units will be issued by August 25, 1984. Ibring the interim, the cognizant System Engineer will perform visual inspections en the normally energized relays on both units once a month.
Also, he will provide a status report on the inspecticn to the Regulatory Compliance group.
The procedural instructions will be based on the recommendations of GE SIL No. 44, Supplement 4.
Item c.
"Frovide 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 Ib and any other preventive and/or corrective measures taken or planned."
700775
Georgia Power 1 U. S. Nuclear Regulatory Commission Office ~of Inspection and Biforcement Region II - Suite 2900 July 13,1984 Page Four Response to Item c:
. As is noted in both the subject I 4 E Bulletin and also in the appropriate GE SILs, the primary cause of HFA relay failure is aging of the coil insulation.
Since aging of the coil typically results in
-visible degradation of. the insulation well before relay failure actually occurs, GFC has determined that the monthly program of visual inspections and functional tests described in the Responses to Items "a"
and "b" above are adequate to ensure that the functions of-
-safety-related equipment will not be compromised by degraded HFA relays.
Site personnel involved in the inspection and maintenance of these devices have been thoroughly briefed on identification of preliminary coil degradation symptoms, and also on the importance of the interim inspection program. hirthermore, the interim period prior to replacement of these releys is estimated to be less than 3 months for the Hatch-1 RFS relays and less than 18 months for other Hatch-1 relays and less than 1 year for Hatch-2 based on current refueling outage scheduling.
Sincerely yours, ZW L. T. Gucwa CBS r
xc:
J. T. Beckham, Jr.
H. C. Nix, Jr.
Senior Resident Inspector 7C3775