Information Notice No. 88-88, Supplement 1: Degradation of Westinghouse ARD Relays
UNITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF NUCLEAR REACTOR REGULATION WASHINGTON, D.C. 20555 May 31, 1989 Information Notice No. 88-88, SUPPLEMENT 1: DEGRADATION OF WESTINGHOUSE ARD RELAYS Addressees: All holders of operating licenses or construction permits for nuclear power reactors. Purpose: This information notice is being provided to update information regarding problems identified in Westinghouse ARD relays. It is expected that recipi- ents will review the information for applicability to their facilities and consider actions, as appropriate, to avoid similar problems. However, sugges- tions contained in this information notice do not constitute NRC requirements; therefore, no specific action or written response is required. Description of Circumstances: Information Notice No. 88-88 discussed a deficiency identified by Pacific Gas and Electric Co. (PG&E) regarding the sand-based coil potting compound used in Westinghouse ARD relays. According to PG&E, this compound had apparently deteriorated and granules had migrated to the coil spool area where they lodged between the relay's coil spool and armature. The increased armature drag resulted in increased relay contact resistance that affected the signal trans-mitted by these relays in voltage sensitive circuits. Discussion: Westinghouse previously believed that the sand-based compound had been used only in certain ARD relays manufactured before 1972. However, further investi gation by Westinghouse determined that the sand-based coil potting compound was used in the manufacture of safety-related and commercial grade ARD relays until 1981. Westinghouse has indicated that even though PG&E recently identified several relays with degraded sand-based compound, as discussed in Information Notice 88-88, no other similar failures have been reported in recent years. 8905240023 .. IN 88-88, Supplement 1 May 31, 1989 Page 2 of 2 No specific action or written response is required by this information notice. If you have any questions regarding 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: Jaime Guillen, NRR (301) 492-1170 Attachment: List of Recently Issued NRC Information Notices .. Attachment IN 88-88, Supplement 1 May 31, 1989 Page 1 of 1 LIST OF RECENTLY ISSUED NRC INFORMATION NOTICES _____________________________________________________________________________ Information Date of Notice No._____Subject_______________________Issuance_______Issued to________ 89-50 Inadequate Emergency 5/30/89 All holders of OLs Diesel Generator Fuel or CPs for nuclear Supply power reactors. 89-49 Failure to Close Service 5/22/89 All holders of OLs Water Cross-Connect or CPs for nuclear Isolation Valves power reactors. 89-48 Design Deficiency in the 5/22/89 All holders of OLs Turbine-Driven Auxiliary or CPs for nuclear Feedwater Pump Cooling power reactors. Water System 89-47 Potential Problems With 5/18/89 All holders of OLs Worn or Distorted Hose or CPs for nuclear Clamps on Self-Contained power reactors and Breathing Apparatus fuel facilities. 89-46 Confidentiality of 5/11/89 All holders of Exercise Scenarios licenses for fuel cycle facilities and byproduct material licensees having an approved emergency response plan. 89-45 Metalclad, Low-Voltage 5/8/89 All holders of OLs Power Circuit Breakers or CPs for nuclear Refurbished with Sub- power reactors. standard Parts 89-44 Hydrogen Storage on the 4/27/89 All holders of OLs Roof of the Control Room or CPs for nuclear power reactors. 88-82, Torus Shells with Corrosion 5/2/89 All holders of OLs Supp. 1 and Degraded Coatings in or CPs for BWRs. BWR Containments 89-43 Permanent Deformation of 5/1/89 All holders of OLs Torque Switch Helical or CPs for nuclear Springs in Limitorque power reactors. SMA-Type Motor Operators _____________________________________________________________________________ OL = Operating License CP = Construction Permit
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Page Last Reviewed/Updated Tuesday, March 09, 2021