Information Notice No. 88-88, Supplement 1: Degradation of Westinghouse ARD Relays

                                  UNITED STATES
                          NUCLEAR REGULATORY COMMISSION
                             WASHINGTON, D.C.  20555

                                  May 31, 1989

                                                 ARD RELAYS


All holders of operating licenses or construction permits for nuclear power 


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.  


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. 

..                                                       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 

                                   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 

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 

Page Last Reviewed/Updated Friday, May 22, 2015