Part 21 Report - 2000-040
Public Service Electric and Gas Company P.O. Box 236 Hancocks Bridge, New Jersey 08038-0236
Nuclear Business Unit
JAN 8 2000
United States Nuclear Regulatory Commission
Document Control Desk
Washington, DC 20555
10CFR2I INTERIM REPORT, GE MODEL CR2940U301 SWITCH
SALEM GENERATING STATION UNITS I AND 2
FACILITY OPERATING LICENSE NO. DPR-70 AND DPR-75
DOCKET NOS. 50-272 AND 311
Pursuant to the notification requirements of I0CFR2I, Public Service Electric and Gas Company (PSE&G) hereby provides this interim report concerning a potentially reportable deficiency due to failure of two new General Electric (GE) Model CR2940U301 switches. This subject switch consists of a single normally closed contact that is plunger actuated and housed in a molded plastic housing. This switch is also designed to be stacked with other switches of the same model to form a switch assembly. During the past year, two new switches have failed during testing of breakers prior to being installed in the plant. At Salem, the switch is used in the control circuit for GE Magne-Blast breakers as the spring charging motor limit switch. Failure of this switch will prevent the associated breaker from closing on a demand signal.
Based on the application described above, these switches are utilized on breakers in non-safety (group buses and 13KV ring bus) and safety related (vital buses) applications at Salem. Failure of one or more of these switches could prevent breakers from closing on a demand signal. This failure could impact the availability of 4KV vital buses and/or safety related loads associated with a vital bus.
In addition to the failure of the two new switches, there have been three documented failures of GE switches installed on Magne-blast breakers at Salem that were previously evaluated. The failures of the two new GE switches may not relate directly to these failures since the switches on the installed breakers were tested during breaker maintenance and were operated during breaker cycling to support normal plant evolutions (i.e., the switches performed acceptably for a period of time). In the same manner, the failure of the new switches may not directly relate to existing GE switches that are in service at Salem.
The failures of the two new switches appear to be due to a high contact resistance or a binding of the movable portion of the contact assembly that prevents proper contact closure. The actual root cause of this condition is still under investigation, and the vendor (GE) is performing a failure analysis. If the analysis determines that the failures were related, PSE&G would conclude that a substantial safety hazard exists since use of the affected switches/breakers in the Salem vital buses is extensive and failure of multiple switches could result in a condition that would meet the substantial safety hazard criteria. If the failures are determined to be unrelated, the failures will be considered to be independent, isolated failures and not subject to 10CFR21 reporting. The GE failure analysis is expected to be completed by February 29, 2000. PSE&G will also consider the three switch failures on the installed breakers in making the final reportability determination.
Should you have any questions regarding this submittal, please contact C. Manges at (856) 339-3234.
Manager - Licensing
C Mr. H. Miller, Administrator - Region I
U.S. Nuclear Regulatory Commission
475 Allendale Road
King of Prussia, PA 19406
Mr. W. Gleaves
Licensing Project Manager - Salem
U.S. Nuclear Regulatory Commission
One White Flint North
Mail Stop 08BIA
11555 Rockville Pike
Rockville, MD 20852
USNRC Senior Resident Inspector - Salem (X24)
Mr. K. Tosch, Manager IV
Bureau of Nuclear Engineering
P.O. Box 415
Trenton, NJ 08625
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