ML20155C340

Significant Deficiency Rept 137-2 Re Potentially Defective Type Hma Auxiliary Relays.Ge Notification Per 10CFR21 Encl. Potentially Defective Equipment Inspected & Corrected Per Field Disposition Instructions from GE

ML20155C340
Person / Time
Site:	Limerick
Issue date:	06/06/1988
From:	Kowalski S PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC
To:	Murley T Office of Nuclear Reactor Regulation
References
REF-PT21-88-079-000 PT21-88-079-000, PT21-88-79, NUDOCS 8806140165
Download: ML20155C340 (5)

Text

. _ _ ._ _ _

PHILADELPHIA ELECTRIC COMPANY 2301 M ARKET STREET P.O. BOX 8699 PHILADELPHI A PA.19101 misie. ..

• o JUN G1988-NUCLE AR ENGINEERING DEPARTMENT Docket No. 50-353

-e Mr. Thomas E. Murley, Di rector Office of Nuclear Reactor Regulation Director of Nuclear Reactor Regulation United States Nuclear Regulatory Cmmission Mall Station P1-137 Washington, DC 20555

Subject:

Significant Deficiency Report No. 137-2 Potentially Defective Type tf% Aux 111ary Relays Limerick Generating Station, Unit 2 Attachtrent : General Electric Notification in Accordance with 10CFR21, dated 12/16/82 Flie: QUAL 2-10-2 (SDR 137-2) ,

Gentlemen:

The attached letter has brought to our attention a potential deficiency In certain type tf% auxillary relays used at Limerick Generating Station Unit 2. This deficiency has been previously report-ed to the USNRC under the provisions of 10CFR21.

We consider the deficiency described in the attachment as a significant deficiency per 10CFR50.55(e) and are hereby notifying you as reautred.

We believe that the General Electric report submitted under the provisions of 10CFR21 provides the Information required for ,

IPCFR50.55Ce) reporting. Therefore, we anticipate that this letter wiii be our only report to vou on this subject. >

4 I  ?

I

' 8806140165 880606 PDR ADOCK 05000353 ( )

g DCn I i

5

JUN G1988 The potentially defective equipment has been Inspected and cor_

rected in accordance with the fleid disposition Instructions received from General Electric.

Sincerely, m

S. . Kowalski, Vice President Nuclear Engineering Attachments pt/sw/06018802 Copy to: Addressee R. J. Clark, Project Manager LGS W. T. Russell, Administrator, USNRC Reglen I R. A. Gram, Sr. Resident Inspector, LGS-2 I

i l

l l

I

' uo,uuneu GENER AL @ ELECTRIC MANAGEMENT DUSINESS A to m DEPARTMSNT CCNERAL ELEC TAIC COMPANY. 20) CAEAT VALLCY P,APKWAY. MALVER

.I i!

December 16, 1982

- Mr. Charles A. Cameron Manager-Safety Evaluation Programs Huclear Energy Business Operations 175 Curtner Avenuo - H/C 682 San Jose, California 95215 Subj ect; 10CFR21 Notification

Dear Sir:

1 Attached is a copy of a letter addressed to our customers who have purchased HPA relays and desi'gnated 10CFR21 on the purchase order.

In accordance with our normal practice, we have also sent a copy of this letter to the NRC.

Yours truly, ,

I fu ,') .

L.'L. Mankoff

' Manager-Engineering LLM/95 Attachment c

~.

3884009460 POWER SYSTEMS GEN ER AL h ELECTRIC

,M A N A G E M E N T SUSINESS GTNERAL GLCCTAiC COMP ANY. 705 GRCAT VALLEY 'PAAKWAY, M ALVERN, PA 19355 0715 DEPARTMENT Phone (715) 251 7000 i

Gentlemen:

This letter serves to notify"you ,of.a potential deficiency in typa yMA auxiliary relays ma'nufactured;during.1974, h t has been. determined tha t some HMA' relays manufactured in i

1974 have insufficient., clearance between the arma ture tail piece and the molded'p'osts on either side of the tail piece.

(

If this condition exists, twisting of the armature may cause binding of the armature tail piece when the armature is ener-gized and prevent opening of the armature when it is de-energized.

A reYiew of our records Indicates that the pot.enti_a_I de-ficiency oc. curred only in HMA r.eLays_that were manu.factured 197.4.

dur 1974.gh'As a result,Ou r corrective in v e s t'rg a't. fo n was action d i s ctaken l oTe~d~a~t o o l p r o b l em <

to increase the minimum spacing between the armature tail piece and the molded posts to assure free movement of the armature.

Relays manufactured during 1974 can be identified by the date code on the Q.C. Acceptance sticker. The code consists of two numbers followed by any of the following suffixes:

AX, BX, CH, DX, EX, FX, GX, HX, JK, XX, LX, MX. There are no known instances of the potential deficiency existin9 prior to 1974. However, if it is desired to check relays manuface tured before 1974, the date code identification is as follows:

the second 1etter of the date code'wi14-6e a letter preceding I the letter "X" in the 3.lphabet. -For example, AG (1971),

AH (1972), AJ (1973). ~

. continued-m

F 3884009460.

It is recommended that HMA relays with any of the listed date codes be inspected for a minimum of an 0.005 inch clearance between the armature tail piece and the posts.

This can be done by inserting an 0.005 inch feeler gaugu into the ga) on each side of the tail piece. See the sketch on tae attached page. Do not force the gauge, it should slide easily into the gap.

CAUTION:- DE-ENERG12E BOTH THE HMA C0!L AND CONTACT CIRCUlTS TEFORE THE GAP CHECX !S MADE.

If less than 0.005 inch cle6rance exists, it is recommended

- that the gaps be increased to a minimum of 0.005 inch or, that the relay be replaced. The c;ps can be increased by removing material from the moldeo posts. This option retains the original relay in the system'end, eliminates the need for system re-testing.~. To gain ac. cess to'the molded posts, remove the No. 4-48 hex nut that' clamps'the; foot of the armature stop to the molded base and lift th.c.stop and armature tail piece out f rom between the posts.- 6.E.~tdoes';not r.ecommend re-working

'the armature tail piece because this would'r.emove the orotec-tive metal finish and could lead to corrosion. In addition, ter,ultant metal chjpp. or filings .could inhibit relay opera tion.

A new replacement HMA relay can 'be purchased at 50 percent of G.E. Handbook price. Request a new relay by complete model number. G.E. must have a Nuclear damage' waiver for any device -

ordered for installation at any Nuclear site. A century series replacement relay must be used for Class I-E service. This of fer will remain available until July 2,1984.

l l

1 I

1 l

l l

]