Information Notice No. 90-57: Substandard, Refurbished Potter & Brumfield Relays Represented As New

                                UNITED STATES
                           WASHINGTON, D.C.  20555

                              September 5, 1990

Information Notice No. 90-57:  SUBSTANDARD, REFURBISHED POTTER & 
                                   BRUMFIELD RELAYS MISREPRESENTED AS NEW


All holders of operating licenses or construction permits for nuclear power 


This information notice is intended to alert addressees to the discovery of 
rotary, non-latching type relays, originally manufactured by Potter & 
Brumfield (P&B) of Princeton, Indiana, that have been apparently modified 
and/or refurbished and that have been found to be materially and 
functionally substandard, such that they may not operate as required.  The 
affected relays include, but may not be limited to, P&B types MDR-138-8, 
MDR-173-1, MDR-134-1, and MDR-142-1.  It is expected that recipients will 
review this information for applicability to their facilities.  However, 
suggestions contained in this information notice do not constitute NRC 
requirements; therefore, no specific action or written response is required.

Description of Circumstances:

Carolina Power and Light Company's (CP&L's) Shearon Harris Nuclear Power 
Plant recently received a shipment of 22 P&B MDR-type relays.  Although 
these were purchased from Spectronics, Inc., of Mobile, Alabama, an 
authorized distributor of P&B relays, the shipment was received directly 
from their supplier, Stokley Enterprises of Norfolk, Virginia.  CP&L 
purchased the relays as commercial-grade items to be dedicated for use in 
the emergency diesel generator safety bus sequencer system at Shearon 
Harris.  CP&L expected Spectronics to supply new relays from P&B, although 
the purchase order did not so state.  CP&L was alerted to potential quality 
problems when the relays were received much sooner than the normal 10 to 12 
weeks from P&B.  Discrepancies were identified by CP&L during receiving 
inspection, during subsequent examination at Shearon Harris by NRC staff and 
a P&B technical representative, and later during inspection and testing at 
the P&B factory, observed by NRC staff.  The relays were improperly 
adjusted, lacked lubrication, and all failed one or more of the P&B tests.  
They contained assortments of nonstandard and/or substandard parts and 
obsolete parts used by P&B or its predecessor, Magnetic Devices, Inc.  The 
parts were assembled in incorrect, non-original configurations.  These 
conditions, indicative of refurbishment, are listed in Attachment 1 to this 
information notice.


Through a continuing series of inspections at licensee and vendor 
facilities, the NRC staff has learned that Spectronics, Inc., has supplied 


                                                           IN 90-57
                                                           September 5, 1990
                                                           Page 2 of 2

modified and/or refurbished P&B MDR-type relays that are materially and 
functionally substandard directly and/or indirectly to (1) at least three 
nuclear plants, including Shearon Harris, Watts Bar, and Sequoyah; (2) 
various vendors to nuclear plants; (3) at least one dedicator of 
commercial-grade components for nuclear plants, Nutherm International (Mount 
Vernon, Illinois); and (4) possibly one or more electrical equipment 
fabricators for installation in relay and switchgear panels for nuclear 
plants.  These apparently modified and/or refurbished P&B-type relays were 
obtained directly or indirectly from either Stokley Enterprises or The 
Martin Company of Chesapeake, Virginia.  Stokley Enterprises and The Martin 
Company may have supplied such P&B-type relays, and various other types of 
modified and/or refurbished electrical components from other manufacturers, 
to distributors of electrical equipment who deal directly or indirectly with 
nuclear utilities.

This information notice requires no specific action or written response.  If 
you have any questions about the information in this notice, please contact 
one of the technical contacts listed below or the appropriate NRC regional 

                              Charles E. Rossi, Director
                              Division of Operational Events Assessment
                              Office of Nuclear Reactor Regulation

Technical Contacts:  K. R. Naidu, NRR  (301) 492-0980
                     S. D. Alexander, NRR  (301) 492-0995

1.   Conditions Indicative of Substandard/Refurbished Relays
2.   List of Recently Issued Information Notices


                                                       Attachment 1 
                                                       IN 90-57 
                                                       September 5, 1990 
                                                       Page 1 of 1 


The following conditions, observed with P&B MDR-type relays supplied by 
Stokley Enterprises and/or The Martin Company through Spectronics, Inc., 
and/or Nutherm International, may be observed on similar relays supplied 
through various other distributors and dealers and are indicative of 
substandard refurbishment:

1.   Non-standard reddish-brown paint used to stake the nuts securing the 
     motor and rotor assemblies (paint may be wet and adhering to the 
2.   Sloppy coil lead solder joints at terminal strips with possible wicking
3.   Painted relay base grommets (normally clear plastic) for coil leads
4.   Terminal strips fastened with eyelets (discontinued in 1967) instead of 
     rivets currently used by P&B
5.   Grey painted rivets fastening the terminal strip to the relay housing 
     where original P&B relays have unpainted rivets
6.   Field termination screws (supplied with the relays) shipped in brown 
     paper bags instead of heat-sealed, plastic bags
7.   Cartons differing from original P&B cartons in color and labelling and 
     relays packed with bubble wrap instead of wrapped in a plastic bag and 
     packed in styrofoam as done by P&B
8.   Apparently silk-screened nameplates, clearly different from original
9.   Repainted inner bell-surface and relay base marks indicating prior use
10.  Date codes and inspection and testing stamps missing or inconsistent 
     with relay type (as determined by comparison with P&B production 
     records), indicating interchanged relay caps
11.  Cap nuts (discontinued in 1977) on rotor and motor assembly bolts, 
     instead of currently used hex nuts, that are not torqued to P&B 
12.  Incorrect shaft-relay cover clearance, incorrect rotor shaft end play, 
     and lack of bearing lubricant
13.  Coil lead insulation color inconsistent with that of current P&B  
14.  Orange paint (not used by P&B after 1972) on tops of rotor shafts 
15.  Slots on tops of rotor shafts not painted black as currently required
16.  Nonuniform numbers stamped on the contact decks, indicating decks made 
     up from various relays
17.  High potential test failure on coils and between contacts and contact 
18.  Functional test failure - actuation above P&B-specified "maximum 
     operate" [pick-up] voltage and/or drop-out below minimum drop-out 
19.  Widely varying coil winding resistance among relays, indicating 
     manufacture during various periods of time
20.  Incorrect coil - one 125-VDC relay found with 200-VDC coil.  Coil had 
     twice the specified winding resistance and relay actuated at high, 
     out-of-specification operate voltage.

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