ML19209B364
| ML19209B364 | |
| Person / Time | |
|---|---|
| Site: | Haddam Neck File:Connecticut Yankee Atomic Power Co icon.png |
| Issue date: | 09/24/1979 |
| From: | Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | Counsil W CONNECTICUT YANKEE ATOMIC POWER CO. |
| References | |
| NUDOCS 7910090573 | |
| Download: ML19209B364 (1) | |
Text
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[o UNITED STATES g
g NUCLEAR REGULATORY COMMISSION e
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'8 631 PARK AVENUE D
,o KING OF PRUSSIA, PENNSYLVANIA 19406 Docket No. 50-213 Q 2 4 ISIL Connecticut Yankee Atomic Power Company ATTN:
Mr. W. G. Counsil Vice President - Nuclear Engineering and Operations P. O. Box 270 Hartford, Connecticut 06101 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, M
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:
R. Graves, Plant Superintendent D. G. Diedrick, Manager of Quality Assurance J. R. Himmelwright, Licensing Safeguards Engineer
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7910090 5'73
ENCLOSURE 1 Accession No.: 7908220118 SSINS No.: 6830 UNITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT WASHINGTON, D. C.
20555 IE Circular 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.
The 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' Consideration:
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 notched 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 Latil the relay condition is corrected.
No written response to this Circular is required.
If you require additional information regarding this subject, contact the Director of the appropriate NRC Regional Office.
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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 Telatherapy Licenses 79-0.7 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 Fuel 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 Self-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 and Holders of cps 79-12 Potential Diesel 6/28/79 All Power Reactor Generator Turbo-Facilities with an charger Problem OL or 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 Ali >'edical Licensees ment and Distribution except Teletherapy Medi-of Xenon-133 cal Licensees, and all Licensed Radiopharma-ceutical Suppliers
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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 Breathing Apparatus 79-16 Excessive Radiation 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
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