ML19209B387
| ML19209B387 | |
| Person / Time | |
|---|---|
| Site: | Seabrook  |
| Issue date: | 09/24/1979 |
| From: | Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | Tallman W PUBLIC SERVICE CO. OF NEW HAMPSHIRE |
| References | |
| NUDOCS 7910090611 | |
| Download: ML19209B387 (1) | |
Text
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o UNITED STATES E N*) -n( h NUCLEAR REGULATORY COMMISSION g
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- REG 80NI 3 (T s [I'%'O[o 8
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KING OF PRUSSIA, PENNSYLVANIA 19406 Docket Nos. 50-443 sgp 34 U73 50-444 Public Service Company of New Hampshire ATTN:
Mr. W. C. Tallman President 1000 Elm Street Manchester, New Hampshire 03105 Gentlemen:
The enclosed Circular No. 79-20, is forwarded to you for information.
No written response is required.
Should you have any questions related to your understanding of this matter, please contact this office.
Sincerely,
/
sk --
Boyce H. Grier Director
Enclosures:
1.
IE Circular No. 79-20 2.
List of IE Circulars Issued in the Last Six Months cc w/encls:
John D. Haseltine, Project Manager 1116 250
'I910000 6 //
ENCLOSURE 1 Accession No.: 7908220118 S51NS No.: 6830 UNITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECT!0N AND ENFORCEMENT WASHINGT0ti, D. C.
20555 IE Circulz.r No. 79-20 Date:
September 24, 1979 Page 1 of 1 FAILURE OF GTE SYLVANIA RELAY, TYPE PM BULLETIN 7305, CATALOG SU12-11-AC WITH A 120V AC COIL Description of Circumstances:
During inspection of relays in the Engineered Safeguards Actuation System at Metropolitan Edison Three Mile Island Nuclear Station Unit #1, relay 62X2B/RCIA failed to drop out when the coil was deenergized.
The failed relay would not prevent component starting but would have reduced the 2 of 3 coincidence logic to 2 of 2, affecting Decay Heat Closed Cooling Pump A and Nuclear Services Closed Cooling Pump A or B.
Tha cause for failure was attributed to a notch in the armature operating rod.
The notch occurs where the rod vibrates against the magnet assembly due to coil hum.
A review of the history of this component indicates that similar relays failed during 1977 through 1979 at least one of which was attributed to notching.
An inspection of forty-eight (48) relays by this licensee indicated that twenty-five (25) of the relays had detectable notches ranging from 0.001 to 0.003 inches deep.
Recommended Actions for Licensees' Conrideration:
1.
Ensure that all GTE Sylvania Relays Type PM Bulletin 7305, with a 120V AC Coil used in or affecting the operation of safety related equipment are examined to ensure that the armature operating rod is not notthed and is operating freely.
2.
Relays found with detectable notches on the operating rod should be corrected. If correction cannot be accomplished then administrative controls should be initiated to assure demonstrated operation until the relay condition is corrected.
No written response to this Circular is required.
If you require additional information regarding this subject, contact the Direc*.or of the appropriate NRC Regional Office.
1116 251
ENCLOSURE 2 IE Circular No. 79-20 Date:
September 24, 1979 Page 1 of 2 LISTING OF IE CIRCULARS ISSUED IN LAST SIX MONTHS Circular Subject First Date Issued To No.
of Issue 79-06 Failure to Use Syringe 4/19/79 All Holders of and Bottle Shields in Medical Licenses Nuclear Medicine Except Teletherapy Licenses 79-07 Unexpected Speed 5/2/79 All BWR Power Reactor Increase of Reactor Facilities with an Recirculation MG Set OL or CP Resulted in Reactor Power Increase 79-08 Attempted Extortion-5/18/79 All Fus' Facilities Low Enriched Uranium and Licensed Reactors 79-09 Occurrences of Split 6/22/79 All Materials Priority or Punctured Regulator I, Fuel Cycle and Diaphragms in Certain Operating Reactor Sel f-Contained Licensees Breathing Apparatus 79-10 Pipefittings Manu-6/26/79 All Power Reactor factured from Facilities with an Unacceptable Material OL or CP 79-11 Design / Construction 6/27/79 All Applicants for, Interface Problem an' Holders of cps 79-12 Potential Diesel 6/28/79 A'
.r Reactor Generator Turbo-F
.ies with an charger Problem CP 79-13 Replacement of Diesel 7/16/79 All Power Reactor Fire Pump Starting Facilities with an Contactors OL or CP 79-14 Unauthorized Procure-7/16/79 All Medical Licensees ment and Distribution except Teletherapy Medi-of Xenon-133 cal Licensees, and all Licensed Radiopharma-ceutical Suppliers ii16 252
2 IE Circular No. 79-20 Date:
September 24, 1979 Page 2 of 2 LISTING OF IE CIRCULARS ISSUED IN LAST SIX MONTHS Circular Subject First Date Issued To No.
of Issue 79-15 Bursting of High Pres-8/8/79 All Materials Priority sure Hose and Malfunc-I, Fuel Cycle and Opera-tion of Relief Valve "0" ting Power Reactor Ring in Certain Self-Licensees Contained Greathing Apparatus 79-16 Excessive Radiatiors 8/16/79 All Radiography Exposures to Members Licensees Of The General Public And A Radiographer 79-17 Contact Problem in 8/14/79 All Power Reactor SB-12 Switches on Licensees with an OL General Electric or CP Metalclad Circuit Breakers 79-18 Proper Installation of 9/10/79 All Power Reactor Target Rock Safety-Licensees with an OL Relief Valves of CP 79-19 Loose Locking Devices 9/13/79 All Power Reactor Licensees on Ingersoll-Rand Pumps with an OL or CP 1116 253