Home > NRC Library > Document Collections > General Communications > Information Notices > 1989 > IN 89-23
UNITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF NUCLEAR REACTOR REGULATION WASHINGTON, D.C. 20555 March 3, 1989 Information Notice No. 89-23: ENVIRONMENTAL QUALIFICATION OF LITTON-VEAM CIR SERIES ELECTRICAL CONNECTORS Addressees: All holders of operating licenses or construction permits for nuclear power reactors. Purpose: This information notice is being provided to alert addressees to a potentially generic safety problem involving CIR series electrical connectors manufactured by the Veam Division of Litton Industries. These connectors have been supplied to numerous commercial nuclear plants by Combustion Engineering, Inc. (CE), and have been obtained by at least three plants through other channels. It is expected that recipients will review the information for applicability to their facilities and consider actions, as appropriate, to avoid similar problems. However, suggestions contained in this information notice do not constitute NRC requirements; therefore, no specific action or written response is required. Description of Circumstances: Litton-Veam CIR series multi-pin electrical connectors are used in core exit thermocouple (CET) and reactor vessel level monitoring (RVLM) systems supplied to numerous plants by Combustion Engineering, Inc., and are used in other ap- plications in at least three additional plants. A proprietary qualification test report (CE NPSD-230-P) has been used to document environmental qualifi- cation of the connectors for loss of coolant accident (LOCA) conditions in the CE-supplied systems. During LOCA testing, the connector face seal gasket was completely degraded and elastomeric inserts interacted with simulated contain- ment spray solution which leaked into the connector. Insulation resistances near 1,000 ohms were measured. CE has performed analyses to show that resultant errors are acceptable in CE-supplied CET and RVLM system thermocouple circuits. However, the moisture ingress and resultant low insulation resistances are not acceptable for heater circuits in the RVLM. For that application, CE developed two remedies; one is a clamp, and the other is a new connector design. CE has advised that one of these remedies has been used for all of the RVLM heater circuits. Unmodified CIR connectors are believed to be still in use in other applications. 8902280104 . IN 89-23 March 3, 1989 Page 2 of 2 Details of this concern, including a list of plants believed to be affected, are contained in NRC Inspection Report 99900401/88-01, dated January 10, 1989. Discussion: CE LOCA-tested the Litton-Veam connectors only in thermocouple circuits, which tolerate relatively poor electrical characteristics. In other applications such as transmitter and solenoid valve circuits, licensees are cau-tioned that CE's testing (1) does not establish qualification and (2) strongly suggests qualification problems. Connector failures could result in the loss of the func-tions of connected qualified equipment. No specific action or written response is required by this information notice. If you have any questions about this matter, please contact the technical contact listed below or the Regional Administrator of the appropriate regional office. Charles E. Rossi, Director Division of Operational Events Assessment Office of Nuclear Reactor Regulation Technical Contact: Richard C. Wilson, NRR (301) 492-0997 Attachment: List of Recently Issued NRC Information Notices . Attachment IN 89-23 March 3, 1989 Page 1 of 1 LIST OF RECENTLY ISSUED NRC INFORMATION NOTICES _____________________________________________________________________________ Information Date of Notice No._____Subject_______________________Issuance_______Issued to________ 89-22 Questionable Certification 3/3/89 All holders of OLs of Fasteners or CPs for nuclear power reactors. 89-21 Changes in Performance 2/27/89 All holders of OLs Characteristics of Molded- or CPs for nuclear Case Circuit Breakers power reactors. 88-73, Direction-Dependent Leak 2/27/89 All holders of OLs Supplement 1 Characteristics of Contain- or CPs for nuclear ment Purge Valves power reactors. 89-20 Weld Failures in a Pump 2/24/89 All holders of OLs of Byron-Jackson Design or CPs for nuclear power reactors. 89-19 Health Physics Network 2/23/89 All holders of OLs or CPs for nuclear power reactors, and the following fuel facilities: Nuclear Fuel Services of Erwin, General Atomic, UNC Montville, B&W LRC Lynchburg, and B&W Lynchburg. 89-18 Criminal Prosecution of 2/22/89 All holders of OLs Wrongdoing Committed by or CPs for nuclear Suppliers of Nuclear power reactors. Products or Services 89-17 Contamination and Degra- 2/22/89 All holders of OLs dation of Safety-Related or CPs for nuclear Battery Cells power reactors. 89-16 Excessive Voltage Drop 2/16/89 All holders of OLs in dc Systems or CPs for nuclear power reactors. __________________________________________________________________________________ OL = Operating License CP = Construction Permit ..
Page Last Reviewed/Updated Thursday, March 29, 2012