United States Nuclear Regulatory Commission - Protecting People and the Environment

LICENSEE: MSD, INC                           
SITE: STRUTHERS-DUNN                        EN NUMBER:30322
DOCKET:                                  EVENT DATE: 04-19-96
RX TYPE:                                 EVENT TIME: 00:00
VENDORS:                                NOTIFY DATE: 04-19-96
EMERGENCY CLASS: N/A  REGION: 2 STATE: SC      TIME: 12:03
OPS OFFICER: BOB STRANSKY             
10 CFR SECTION: CDEF  21.21(b)(2)         DEFECTS/NONCOMPLIANCE

10 CFR PART 21 REPORT - INCORRECT COILS INSTALLED IN TIME DELAY  
RELAYS                                                           
                                                                 
THE FOLLOWING IS TEXT EXCERPTED FROM A FACSIMILE SUBMITTED BY THE
VENDOR:                                                          
                                                                 
"IT HAS COME TO OUR ATTENTION THAT A QUANTITY OF STRUTHERS-DUNN  
TYPE 236ABX135NE TIME DELAY RELAYS BUILT IN 1983 HAVE INCORRECT  
COILS IN THEM. SPECIFICALLY, THE AFFECTED RELAYS CONTAIN 39 GAUGE
COILS; THEY SHOULD HAVE 43 GAUGE.  AS A RESULT, THE COILS CONSUME
SEVERAL TIMES THE REQUIRED POWER WHICH IS DISSIPATED AS HEAT, AND
UPON PROLONGED ENERGIZATION MAY OVERHEAT TO THE POINT OF         
SELF-DESTRUCTION.  WE HAVE ONE SUCH OCCURRENCE TO DATE.          
                                                                 
WE BELIEVE THE DEFECT WAS CAUSED BY PERSON OR PERSONS WHO RELIED 
ON MEMORY RATHER THAN DOCUMENTATION WHEN BUILDING THESE DEVICES. 
THEY WERE INTENDED FOR USE ON 125-VOLT DC CIRCUITS; THE COILS    
INSTALLED ARE THOSE NORMALLY USED ON 120-VOLT AC.  SINCE THE     
RELAYS WOULD FUNCTION PROPERLY FOR BRIEF PERIODS, THE DEFECT WAS 
OBVIOUSLY OVERLOOKED.                                            
                                                                 
TO DATE, WE HAVE FOUND NINE RELAYS AS DESCRIBED, ALL AT GEORGIA  
POWER'S PLANT HATCH.  ALL ARE DATE CODED 8335 WHICH INDICATES    
THEY WERE BUILT IN THE 35TH WEEK OF 1983.  WE ARE OF THE OPINION 
THIS WAS THE ONLY TIME THIS OCCURRED, BUT THERE IS NO WAY TO     
PROVE IT ... FORTUNATELY, THESE RELAYS' COILS ARE CLEARLY MARKED,
AND VERIFICATION OF CORRECT COIL GAUGE CAN BE ACCOMPLISHED WITH A
VISUAL INSPECTION ... AGAIN, WE BELIEVE PLANT HATCH HAS THE ONLY 
ONES, BUT WE CANNOT BE CERTAIN."                                 
                                                                 
THE ASSETS OF STRUTHERS-DUNN WERE PURCHASED IN 1990 BY MSD, INC. 

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