ML19331C298
| ML19331C298 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 07/31/1980 |
| From: | Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | Arnold R METROPOLITAN EDISON CO. |
| References | |
| NUDOCS 8008140516 | |
| Download: ML19331C298 (1) | |
Text
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o UNITED STATES
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NUCLEAR REGULATORY COMMISSION e
,N REGION I 2
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631 PARK AVENUE
,d KING OF PRUSs!A. PENNSYLVANIA 19406 Docket *Nos. 50-289 50-320 Metropolitan Edison Company ATTN:
Mr. R. C. Arnold Senior Vice President 100 Interpace Parkway Parsippany, New Jersey 07054 Gentlemen:
Enclosed is IE Bulletin No. 80-20 which requires action by you with respect to your nuclear power facility (ies).
In order to assist the NRC in evaluating the value/ impact of each Bulletin on licensees, it would be helpful if you would provide an estimate of the manpow'ar expended in conduct of the review and preparation of the report (s) required by the Bulletin. Please estimate separately the manpower associated with corrective actions necessary following identification of problems through the Bulletin.
Should you have any quertions regarding the Bulletin or actions required by you, please contact this office.
Sincerely, B y e li. Grier Director
Enclosures:
1.
IE Bulletin No. 80-20 with Enclosure 2.
List of Recently Issued IE Bulletins CONTACT:
E. G. Greenman (215-337-5267) cc w/encis:
J. G. Herbein, Vice President-Nuclear Operations E. G. Wallace, Licensing Manager R. J. Toole, Manager, Unit 1 W. E. Potts, Manager, Radiological Controls, Unit 1 J. W. Brasher, Manager, Radiological Controls, Unit 2 J. J. Colitz, Manager, Plant Engineering, Unit 1 J. J. Barton, Manager Site Operations, Unit 2 B. Elam, Manager, Plant Engineering, Unit 2 R. F. Wilson, Director - Technical Functions L. W. Harding, Supervisor of Licensing G. K. Hovey, Director, Unit 2 I. R. Finfrock, Jr.
R. W. Conrad J. B. Lieberman, Esquire G. F. Trowbridge, Esquire Ms. Mary V. Soutbard, Chairperson, Citizens for a Safe Environment 8 0 0 814 0 GIG
ENCLOSURE 1 SSINS No.: 6820 UNITED STATES Accession No.:
NUCLEAR REGULATORY COMMISSION 8006190023 0FFICE OF INSPECTION AND ENFORCEMENT WASHINGTON, D.C.
20555 July 31, 1980 IE Bulletin No. 80-20 i
Page 1 of 2 FAILURES OF WESTINGHOUSE TYPE W-2 SPRING RETURN TO NEUTRAL CONTROL SWITCHES By letter dated June 18, 1980, Commonwealth Edison Company submitted Licensee Event Report No. LER 50-295/80-24 to the NRC describing a malfunction of a Westinghouse Type W-2 control switch at the Zion Generating Station, Unit 1.
The malfunctioning switch is a three position spring return to nrutral switch.
Although the switch was in its proper neutral position when it malfunctioned, its r.cutral contacts failed to close properly thereby preventing the automatic start of 1A Service Water Pump.
Subsequent tests conducted on the malfunctioning switch revealed that contact closure was intermittent with the switch in the neutral (or " Auto Start")
position.
Other tests conducted on identical switches from spares and from Unit 2 equipment disclo;9d two additional switches with a tendency for inter-mittent contact closun A review of this matter by Westinghouse led to the issuance of NSD Technical Bulletin No. NSD-TB-80-9 to the utility owners of all Westinghouse operating plants.
The recommendatio.ns contained in the Westinghouse technical bulletin include: (i) testing the neutral position contacts of the subject W-2 switches for continuity, and (ii) rewiring of the indicating light circuit to permit the early detection of a neutral contact failure as shown in Figure 1.
Depending on how the indicating light circuit is wired, loss of continuity thru the neutral position contact of a W-2 sw% wh c2uld remain undetected until the equipment associated with the switch.ere called upon to operate.
Since such a failure would be equivalen' iD ay".assing the system associated 5ith the switch, consideration should (c jisp
,,a rewiring the switches used in safety-related applications as shown in FigurJ 1.
Such rewiring would provide an acceptable means for detecting contact failure, provided the indicating light is in the control room and readily visi.ble by the operator.
If the indicating light is not so located, consideration should be given to annunciating the neutral position contact failures at the control room to alert the operator of the inoperable status of a safety-related rystem.
In addition, consideration should be given to adding redundant contacts to the W-2 switches or to replating the W-2 switches with others having a more posi-tive contact wiping action.
IE Bulletin No. 80-20 July 31, 1980 Page 2 of 2 ACTIONS TO BE TAKEN BY LICENSEES AND HOLDERS OF CONSTRUCTION PERMITS:
1.
Determine whether Westinghouse Type W-2 control switches with spring return to neutral position are used in safety-related applications E.t your facility.
If so, identify the safety-related systems using these switches and the total number of switches so used.
If no such switches are used in your facility, you should indicate that this is the case and ignore the remaining questions.
2.
Licensees of operating plants using Type W-2 spring return to neutral control switches in safety-related applications shall perform continuity tests on all such switches. These tests shall be performed with the switch operator in the neutral position and completed within ten (10) days of the date of this bulletin.
In addition, this continuity test shall be repeated at least every thirty-one (31) days after the initial test and after each manipulation of the switch from its neutral position.
These continuity tests may be discontinued subsequent to implementing the longer term corrective measures described below.
3.
Licensees of operating plants and holders of construction permits shall describe the longer term corrective measures planned and the date by which such measures will be implemented by actual installation or by design change, as appropriate.
As a minimum, the longer term corrective n:casures should include rewiring the indicating light as shown in Figure 1 provided the light is readily visible to the control room operator.
If not, failures of the neutral position contacts should be annunicated in the control room.
A report addressing the above matters, including the number of failures detected during the first series of tests and the safety-related systems involved, shall be suomitted to the director of the appropriate NRC regional office within forty-five (45) days of the date of this bulletin. A copy of the report shall be forwarded to the Director, Division of Keactor Operations hspection, Office of Inspection and Enforcement, Nuclear Regulatory Commission, Washington, D. C. 20555.
Approved by GAO, B180225 (R0072); clearance expires 7/31/80.
Approval was given under a blanket clearance specifically for identified generic problems.
Enclosure:
Figure 1
Enclosure to XE Bulletin No. 80-20 EXIS1!NG INDICATING LIGHT CIRCUIT (TYPICAL)
NEUTRAL SWITCH
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CONTACT INDICATING LIGHT L
T sI
'M 5
SAFETY
(-)
SIGN %
(-)
FROPOSED MEWIRING OF INDICATING LIGHT CIRCUIT (TYPICAL) l NEUTRAL SWITCH
~,.4 CONTACT 7" c
INDICATING s%
LIGHT 1
Q/
J V
Y l
SAFETY
=L SIG!!AL Nlt/
sf 9)
(-)
FIGURE 1 REWIR'.NG Of INDICAT '.3 LIGHT CIRCUIT Gr U-I SWITCHES AS RECO*.*. ENDED BY WESTINGNL'SE TECHNIC AL BULLETIN N50-T3-80-9
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IE Bulleti-No. 80-20 July 31, 1130 RECENTLY ISSUED IE BULLETINS Bulletin Subject Date Issued Issued To No.
80-19 Failures of Mercury-7/31/80 All nuclear power Wetted Matrix Relays in facilities having Reactor Protective Systems either an OL or a CP of Operating Nuclear Power Plants Designed by Combus-tion Engineering 80-18 Maintenance of Adequate 7/24/80 All PWR power reactor Minimum Flow Thru Centrifugal facilities holding OLs Charging Pumps Following and to those PWRs Secondary Side High Energy nearing licensing Line Rupture Supplement 2 Failures Revealed by 7/22/80 All BWR power reactor to 80-17 Testing Subsequent to facilities holding OLs Failure of Control Rods to Insert During a Scram at a BWR Supplement 1 Failure of Control Rods 7/18/86 All BWR power reactor to 80-17 to Insert During a Scram facilities holding OLs at a BWR 80-17 Failure of Control Rods 7/3/80 All BWR power reactor to Insert During a Scram facilities holding OLs at a BWR 80-16 Potential Misapplication of 6/27/80 All Power Reactor Rosemount Inc., Models 1151 Facilities with an and 1152 Pressure Transmitters OL or a CP with Either "A" or "D" Output Codes 80-15 Possible Loss Of Hotline 6/18/80 All nuclear facilities With Loss Of Off-Site Power holding OLs 80-14 Degradation of Scram 6/12/80 All BWR's with an Discharge Volume Capability OL 80-13 Cracking In Core Spray 5/12/80 All BWR's with an Spargers OL 80-12 Decay Heat Removal System 5/9/80 Each PWR with an OL Operability i
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