ML19209C208
| ML19209C208 | |
| Person / Time | |
|---|---|
| Site: | Humboldt Bay, Diablo Canyon |
| Issue date: | 09/24/1979 |
| From: | Engelken R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V) |
| To: | Crane R PACIFIC GAS & ELECTRIC CO. |
| References | |
| NUDOCS 7910120203 | |
| Download: ML19209C208 (1) | |
Text
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UNITED STATES
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(g NUCLEAR REGULATORY COMMISSION
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n U E ',1 1990 N. CAltFORNIA COULEVARD O
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Y/4 SUlTE 202, WALNUT CREEK PLAZA
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WALFJUT CREE K. CALIFORNI A 9459G September 24, 1979 Docket Nos. 50-133 50-275 50-: :
Pacific Gas and Electric Company 77 Beale Street San Francisco, California 94106 Attention: Mr. Philip A. Crane, Jr.
Assistant General Counsel Gentlemen:
The enclose'l IE 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, k
+ m e&L R. H. Engelken Director
Enclosures:
1.
IE Circular No. 79-20 2.
List of IE Circulars Issued in the Last Six Months cc w/ enclosures:
W. Barr, PG&E W. Raymond, PG&E R. Ramsay, PG&E, Diablo Canyon E. Weeks, PG&E, Humboldt Bay J. Worthington, PG&E l144 057 Y910120 20,3 9
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2J oo Accession tio.: 7908220118 SSINS No.: 6830 UNITED S1ATES NUCLEAR REGULATORY COMt11SS10N OFFICE OF INSPECTION AND ENFORCEMENT WASHINGTON, D.C.
20555 September 24, 1979 IE Circular No. 79-20 FluLGRE OF GTE siLvANIA RELA), TYPE FM BULLETIh 7305, CATALCG 5U12-11-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 hun. 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 fron 0.001 to 0.003 inches deep.
Reconnended Acticns 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 arnature 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 acccmplished 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 Director of the appropriate NRC Regional Office.
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IE Circular No. 79-20 Enclosure September 24, 1979 Page 1 of 2 LISTING 0F IE CIRCULARS ISSUED IN LAST SIX MONTHS Circular Subject Date of Irsued to No.
Issue 79-03 Inadequate Guard Training-2/23/79 All Holders of Qualification and Fulsified and applicants
' 2' 2 : Rec rds for Specia' Nuclear Material Licenses in Safeguards Group I 79-04 Loose Locking Nut On 3/16/79 All Holders of Linitorque Valve Reactor OLs or cps Operators 79-05 Moisture Leakage In 3/20/79 All Holders of Stranded Wire Conductors Reactor GLs or cps 79-06 Failure to Use Syringe 4/19/79 All Holders of and Bottle Shields in Medical Licensees Nuclear Medicine except teletherapy licensees 79-07 Unexpected Speed Increase 5/2/79 All Holders of of Reactor Recirculation BWR OL's or CP's MG Set Resulted in Reactor Power Increase 79-08 Attenpted Extortion - Low 5/18/79 All Fuel Facilities Enriched Uranium Licensed by MRC 79-09 Occurrences of Split or 6/22/79 All Materials Punctured Regulator Diaphragms Priority I, Fuel In Certain Self Contained Cycle and Operating Breathing Apparatus Reactor Licensees 79-10 Pipefittings Manufactured 6/26/79 All Power Reactor from Unacceptable Material Licensees with a CP and/or OL 79-11 Design / Construction 6/27/79 All Applicants Interface Problem for, and Holders of Power Reactor cps Ii44 059
IE Circular No. 79-20 Enclosure September 24, 1979 Page 2 of 2 LISTING OF IE CIRCULARS ISSUED IN LAST SIX MONTHS Circular Subject Date of Issued to No.
Issued 79-12 Potential Diesel Generator 6/28/79 All Power Reactors Turbocha*ger Droblem Goerating Facilities ano all Utilities having a CP 79-13 Replacement of Diesel 7/10/79 All Power Reactor Fire Pump Starting Operating F:.cilities Contactors and all Utilities having a CP 79-14 Unauthorized Procurement and 7/13/79 All Medical Licensees Distribution of XE-133 except Teletheraphy Medical Licensees and to all Radiopharmaceu-tical Suppliers 79-15 Bursting of High Pressure Hose 8/8/79 All Materials Priority I, and Malfunction of Relief Fuel Cycle and Operating Valve "0" Ring in Certain Self-Power Reactor Licensees Contained Breathing Apparatus 79-16 Excessive Radiation Exposures 8/16/79 All Radiography To Members Of The General Public Licensees And A Radiographer 79-17 Contact Problem in SB-12 8/14/79 All Power Reactor Switches on General Electric Licensees with a CP Comp 6ny Metalclad Circuit and/or OL Breakers 79-18 Proper Installation of 9/10/79 All Holders of a Target Rock Safety-Relief Power Reactor OL Valves or CP 79-19 Loose Locking Devices on 9/13/79 All Power Reactor Ingersoll-Rand Pumps Operating facilities and all utilities having a CP 1144 060