ML19207B552
| ML19207B552 | |
| Person / Time | |
|---|---|
| Site: | Dresden  |
| Issue date: | 08/15/1979 |
| From: | Pappas H NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| References | |
| NUDOCS 7908300242 | |
| Download: ML19207B552 (3) | |
Text
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o, UNITED STATES 3
NUCLEAR REGULATORY COMMISSION 3,
e REGION 111
. 8 799 ROOSEVELT ROAD o,
E GLEN ELLYN, ILLINOIS 60137
%,.....,o wut 5 wg MEMORANDUM FOR: Those on Attached List FROM:
Helen Pappas, Chief, Administrative Branch
SUBJECT:
IE Circular No. 79-17 The attached IE Circular No. 79-17, titled, " Contact Problem in SB-12 Switches on General Electric Company Metalclad Circuit Breakers was sent to the following licensees on August 14,1979, for information:
American Electric Power Service Corporation Indiana and Michigan Pcver Company D. C. Cook 1, 2 (50-3 3, 50-316)
Cincinnati Gas & Electric Company Zimmer (50-358)
Cleveland Electric Illuminating Company Perry 1, 2 (50-440, 50-441)
Commonwealth Edison Company Braidwood 1, 2 (50-456, 50-457)
Byron 1, 2 (50-454, 50-455)
Dresden 1, 2, 3 (50-10, 50-237, 50-249)
La Salle 1, 2 (50-373, 50-374)
Quad-Cities 1, 2 (50-254, 50-265)
Zion 1, 2 (50-295, 50-304)
Consumers Power Company Big Rock Point (50-155)
Midland 1, 2 (50-329, 50-330)
Palisades (50-255)
Dairyland Power Cooperative LACBWR (50-409)
Detroit Edison Company Fermi 2 (50-341)
Illinois Power Company Clinton 1, 2 (50-461, 50-462) 7 90,830 oza a 852 343
Those on Attached List nwe i 5 t373 Iowa Electric Light & Power Company Duane Arnold (50-331)
Northern Indiana Public Service Company Bailly (50-367)
Northern States Power Company i
Monticello (50-263)
Prairie Island 1, 2 (50-282, 50-306)
Tyrone Energy Park 1 (50-484)
Public Service of Indiana Marble Hill 1, 2 (50-546, 50-547)
Toledo Edison Company Davis-Besse 1 (50-346)
Union Electric Company Callaway 1, 2 (50-483, 50-486)
Wisconsin Electric Power Company Point Beach 1, 2 (50-266, 50-301)
Wisconsin Public Service Corporation Kewaunee (50-305)
The Ohio Edison Company Pre-CPP n" U.$cd
/
Helen Pappas, Chief Adninistrative Branch
Attachment:
1.
lE Circular No. 79-17 2.
List of IE Circulars Issued in the Last 6 Months 852 344
Addressees - Memorandum dated August 15, 1979 g%15 69 IE Files AD/FFMSI/IE NMSS/FCSL (AD)
NMSS/FCWM (AD)
NMSS/FCMS (AD)
MPA/.DTS CENTRAL FILES REPRO UNIT PDR NSIC l' A b f) '") ^'
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Accession No:
7908090272
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SSINS: 6830 UNITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT WASHINGTON, D.C.
20555 August 14, 1979 IE Circular No. 79-17 CONTACT PROBLEM IN SB-12 SWITCHES ON GENERAL ELEC1RIC METALCLAD CIRCUIT BREAKERS The General Electric Company, Switchgear Department in Philadelphia, reported to the NRC on July 3,1979, an intermittent contact problem in SB-12 switches.
This intermittent contact problem will cause a lack of continuity through the "a" contact of the switch that is used to energize the trip coil of the circuit breaker.
Investigation disclosed that a die used to form a hole in the contact arms of the switch had worn, resulting in elongated holes. This condition could permit the contact bridge member to move laterally relative to the contact arm, occasionally resulting in improper "a" contact wipe.
The worn die has been corrected, and all switches shipped on or after July 1,1979, include this correction. A review of the history of these components indicates that switches shipped in the time period of August 1, 1978 to July 1, 1979, could have this problem. The trip coil and auxiliary switch portion of the trip circuit is monitored for continuity by a red light on the front door of the switchgear.
This light is lit when the breaker is closed and the control circuits are energized.
If the red light is lit, this indicates that the "a" contacts of the switch are closed, and that a trip signal will trip the breaker.
Based on the above, the licensees are advised to do the following:
1.
Insure that all General Electric Company Metalclad Circuit Breakers shipped to your facilities during the period from August 1,1978 to July 1, 1979 and used in or affecting the operation of safety related equipment are furnished with new SB-12 control switches as promptly as possible.
2.
Pending replacement of SB-12 control switches administrative controls should be initated to assure the red light which demonstrates contact continuity, is lit and remains lit each time these circuit breakers are closed.
No written response to this circular is required.
If you require additional information regarding this subject, contact i.ne Director of the appropriate NRC Regional Office.
852 346
IE Circular No. 79-17 Enclosure August 14, 1979 Page 1 of 2 LISTING OF IE CIRCULARS ISSUED IN LAST SIX MONTHS Circular Subject Date of Issued to No.
Issue 79-03 Inadequate Guard Training-2/23/79 All Holders of Qualification and Falsified and applicants Training Records for Special Nuclear Material Licenses in Safeguards Group I 79-04 Loose Locking Nut On 3/16/79 All Holders of Limitorque Valve Reactor OLs or cps Operators 79-05 Moisture Leakage In 3/20/79 All Holders of Stranded Wire Conductors Reactor OLs or cps 79-06 Failure to Use Syringe 4/19/79 All Holders of and Battle 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 Resu. ad in Reactor Power Increase 79-08 Attempted Extortion - Low 5/18/79 All Fuel Facilities Enriched Uranium Licensed by NRC 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 852 347
IE Circular No. 79-17 Enclosure August 14, 1979 Page 2 of 2 LISTING OF IE CIRCULARS ISSUED IN LAST SIX HONTHS Circular Subject Date of Issued to No.
Issued 79-12 Potential Disel Generator 6/28/79 All Power Reactors Turbocharger Problem Operating Facilities and all Utilities having a CP 79-13 Reple.r* ment of Diesel 7/10/79 All Power Reactor Fire Peeo Starting Operating Facilities 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" Rin, in Certain Self-Power Reactor Licensees Contained Breathing Apparatus 79-16 Excessive Radiation Exposures 8/16/79 All Radiography To Hembers Of The General Public Licensees And A Radiographer B32 348
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