ML20079L264

Followup Rept Re Deficient Hma Type Relays Mfg by Ge. Initially Reported on 821207.Survey of Hma Relays Mfg Prior to & During 1974 Conducted.Relays Will Be Replaced.Survey & Replacement Will Be Completed by 830531

ML20079L264
Person / Time
Site:	Shoreham File:Long Island Lighting Company icon.png
Issue date:	02/07/1983
From:	Milligan M LONG ISLAND LIGHTING CO.
To:	Haynes R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
References
10CFR-050.55E, 10CFR-50.55E, SNRC-833, NUDOCS 8302230200
Download: ML20079L264 (2)

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- l y-== = -- m j i LONG ISLAND LIGHTING COMPANY h fm.fagf ,f , SHOREHAM NUCLEAR POWER STATION im-- ww- d P.O. BOX 618, NORTH COUNTRY ROAD + WADING RIVER, N.Y.11792 Direct Dial Number February 7, 1983 SNRC-833 Mr. Ronald C. Haynes Office of Inspection & Enforcement - Region I U. S. Nuclear Regulatory Commission King of Prussia, PA 19404 Shoreham Nuclear Power Station - Unit 1 Docket No. 50-322

Dear Mr. Haynes:

On December 7, 1982, in accordance with 10CFR50.55 (e) , we reported verbally to Region I a deficiency with HMA type relays manufactured by General Electric Company. A 30-day written report of this defi-ciency was submitted on December 7, 1982 (Reference SNRC-806).

This letter serves as a follow-up report.

Description of Deficiency During the performance of Startup testing of Shoreham's 4.16KV emergency switchgear breakers, a breaker was observed which failed to operate when called to close. As a result of the investigation of the breaker misoperation, it was determined that a General Electric type HMA relay had " hung up" in its energized position after being de-energized. This HMA relay was utilized in the breaker's anti-pump circuit and its failure to open when de-ener-gized prevented the proper operation of the Class lE breaker when called to close.

Further investigation and examination of the defective f31ay indicates that the problem is caused by a rubbing condition between the relay's pivoting contact plate and its two stationary contact posts. The problem appears to be sporadic in nature and infrequent in its rate of occurrence. It is surmised that HMA relays exhibiting this defect may have prevented closure of two other switchgear breakers during testing, but in both those cases, the " hung-up" relay opened while the breakers were being lowered and pulled out of their cubicles for examination. The relays and breakers then functioned properly during subsequent inspections.

Although HMA relays are utilized in several applications at Shoreham, only one case involving a 4.16KV switchgear breaker has been posi-tively identified.

8302230200 830207 PDR ADOCK 05000322 S pon FC-89 35.1

February 7, 1983 SNRC-833 Page 2

-Corrective Action

. General Electric has determined that some HMA relays manufactured in 1974 have insufficient clearance between the armature tail piece and the molded parts on either side of the tail piece. .As a result of this deficiency, General Electric Company issued Service Advice Letter 721-PSM-171.1.

A field survey of all HMA relays manufactured prior to and during 1974 has been initiated to determine if any of these relays

' installed'at Shoreham exhibit the spacing deficiency as-described in the Service Advice Letter.

Additionally, General Electric Company is providing new HMA relays as spares / replacements should any' additional defective relays be found. According to our present schedule, we estimate that the field survey and replacement program will be completed by May 31, 1983.

-Very truly yours,

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M. H. Milligan Project Engineer Shoreham Nuclear Power Station JSK:mp cc: J. Higgins All parties