United States Nuclear Regulatory Commission - Protecting People and the Environment


ACCESSION #:  9609170010



                              Public Service

                              Electric and Gas

                              Company



E.C.Simpson   Public Service Electric   P. O.  Box 236,     609-339-1700

              and Gas Company           Hancocks Bridge,

                                        NJ 08038

Senior Vice President -

 Nuclear Engineering                      LR-N96274



                                          SEP 06 1956



United States Nuclear Regulatory Commission

Document Control Desk

Washington, DC 20555



Gentlemen:



10 CFR 21 NOTIFICATION, NUS SUMMATOR AND ISOLATOR MODULES

SALEM GENERATING STATION UNITS 1 AND 2

FACILITY OPERATING LICENSE NO. DPR-70 AND DPR-75

DOCKET NOS.  50-272 AND 50-311



Pursuant to the notification requirements of 10 CFR 21.21(d)(3)(ii),

Public Service Electric and Gas Company (PSE&G) is providing the attached

written notification on the identification of a defect in NUS summator

and isolator logic modules.  PSE&G identified this deviation on June 25,

1996 and made initial notification to the NRC Operations Center as

required by 10 CFR 21.21(d)(3)(i) on August 8, 1996.



Should you have any questions, please contact us.



                                        Sincerely,



Attachment (1)



Document Control Desk             -2-                         SEP 06 1996

LR-N96274



C    Mr.  H.  J.  Miller, Administrator - Region I

     U.  S.  Nuclear Regulatory Commission

     475 Allendale Road

     King of Prussia, PA 19406



     Mr.  L.  Olshan, Licensing Project Manager Salem

     U.  S.  Nuclear Regulatory Commission

     One White Flint North

     11555 Rockville Pike

     Mail Stop 14E21

     Rockville, MD 20852



     Mr.  C.  Marschall (X24)

     USNRC Senior Resident Inspector



     Mr.  K.  Tosch, Manager IV

     Bureau of Nuclear Engineering

     33 Arctic Parkway

     CN 415

     Trenton, NJ 08625



     NUS

     P.O.  Box 50736

     Idaho Falls, ID 83405



10 CFR 21 Notification

NUS Summator and Isolator Modules



I.        NAME AND ADDRESS OF THE INDIVIDUAL(S) INFORMING

          THE COMMISSION.



          NAME:

          E.  C.  Simpson

          Senior Vice President - Nuclear Engineering



          ADDRESS:

          Public Service Electric and Gas Company P.O.  Box 236

          Hancock's Bridge, NJ 08038



II.       IDENTIFICATION OF THE FACILITY, ACTIVITY OR COMPONENT WHICH

          FAILS TO COMPLY OR CONTAINS A DEFECT.



          The facility is the Salem Generating Station, Units 1 and

          2.  The basic components are Reactor Control and Protection

          System signal isolator and signal summator modules:



               Isolator module          Model No.  OCA801

               Summator module          Model No.  MTH801



III.      IDENTIFICATION OF THE FIRM SUPPLYING THE BASIC COMPONENT

          WHICH FAILS TO COMPLY OR CONTAINS A DEFECT.



          The modules were manufactured by:



          NUS

          P.O.  Box 50736

          Idaho Falls, ID 83405



IV.       NATURE OF THE DEFECT OR FAILURE TO COMPLY AND THE SAFETY

          HAZARD WHICH IS CREATED OR COULD BE CREATED.



          NUS Model OCA801 signal isolator modules and Model MTH801

          Signal Summator Modules are being installed as replacements for

          modules in the Hagan 7100 Reactor Control and Protection System

          to provide improved reliability.  During bench testing, an

          electrical connection with no solder was observed on a

          replacement summator module.  The replacement summator and

          isolator modules for Salem Unit 2



Attachment 1                      -2-



          were then inspected.  Of 220 modules inspected, fifteen were

          found to have solder workmanship deficiencies (i.e., joints

          with no solder or with insufficient or cold solder).  Some of

          the defective connections were covered by heat shrink

          insulation.



          The isolator modules function to provide electrical separation

          between the Reactor Protection System (Class 1E) and the

          Process Control System (non-Class 1E) portions of the Reactor

          Control and Protection (RCP) instrument loops.  The summator

          modules are used to algebraically combine analog signals,

          either adding or subtracting inputs in combination with module

          gain and bias.



          The reactor protection system is designed to assure that the

          system can perform its required functions in the event of a

          design basis earthquake.  The missing and defective solder

          joints could affect the modules' ability to function during a

          design basis earthquake.  It is not practical to determine the

          exact failure modes introduced by these defects for each plant

          application.  However, due to the interchangeability of the

          modules, the defects could result in a loss of redundancy

          sufficient to constitute a major degradation of essential

          safety related equipment.



V.        THE DATE ON WHICH THE INFORMATION OF SUCH DEFECT OR

          FAILURE TO COMPLY WAS OBTAINED.



          The information was obtained on June 25, 1996.



VI.       IN THE CASE OF A BASIC COMPONENT WHICH CONTAINS A DEFECT OR

          FAILS TO COMPLY, IDENTIFY THE NUMBER AND LOCATION OF ALL SUCH

          COMPONENTS IN USE AT OR SUPPLIED FOR PSE&G FACILITIES SUBJECT

          TO THE REGULATIONS OF 10 CFR 21.



          219 replacement modules are being installed or kept as spares

          for Salem Unit 2.  The replacement modules for Salem Unit 1

          have been returned to the vendor.



Attachment 1                      -3-



VII.      THE CORRECTIVE ACTION WHICH HAS BEEN, IS BEING, OR WILL BE

          TAKEN; THE NAME OF THE RESPONSIBLE INDIVIDUAL OR ORGANIZATION;

          AND THE LENGTH OF TIME THAT HAS BEEN OR WILL BE TAKEN TO

          COMPLETE THE ACTION.



          The replacement modules including spares for Salem Unit 2 have

          been inspected by the vendor and repaired.  The replacement

          modules for Salem Unit 1 have been returned to the vendor for

          inspection and repair.



          PSE&G requested the vendor to perform a root cause analysis of

          the deficiencies.  NUS provided a report of their evaluation to

          PSE&G on September 3, 1996.  NUS concluded that the soldering

          workmanship deficiencies were due primarily to failure to

          perform self-verification by assembly personnel and inadequate

          supervisory monitoring of module assembly.  NUS stated that

          they had taken action to prevent recurrence and had

          communicated the results of their inspection to affected

          personnel.



VIII.     ANY ADVICE RELATED TO THE DEFECT OR FAILURE TO COMPLY THAT

HAS

          BEEN, IS BEING, OR WILL BE GIVEN TO PURCHASERS OR LICENSEES.



          None.



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