ML19344F140
| ML19344F140 | |
| Person / Time | |
|---|---|
| Site: | Rancho Seco |
| Issue date: | 08/27/1980 |
| From: | Engelken R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V) |
| To: | Mattimoe J SACRAMENTO MUNICIPAL UTILITY DISTRICT |
| References | |
| NUDOCS 8009120465 | |
| Download: ML19344F140 (1) | |
Text
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' UNITED STATES 8*{
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NUCLEAR REGULATORY COMMISSION U '-
/E REGION V 1990 N. CALIFORNIA BOULEVARD
.,8 SulTE 202, WALNUT CREEK PLAZA
- e,e*
WALNUT CREE K, CALIFORNI A 94596 August 27, 1930 Docket flo. 50-312 Sacramento fiunicipal Utility District P. O. Box 15830 Sacramento, California 95813 Attention: Mr. John J. Mattimoe Assistant General Manager Gentlemen:
This Information flotice is provided as a notification of a matter of possible safety significance.
It is expected that recipients will review the information for possible applicability to their facilities, and where applicable, consider the recommended action.
If you have questions regarding this matter, please contact the director of this office.
Sincerely, l
w/bh R. fl. Engelken Director
Enclosures:
1.
IE Information llotice flo. 80-31 2.
Recently issued IE Infonaation Notices cc w/ enclosures:
R. J. Rodrigugz, SMUD L. G. Schwieger, SMUD
,80.09120j6f
1 SS?"S flo.: 6870 Accession flo. -
8005190040 Ifl 80-31 4
UtlITED STATES IlUCLEAR REGULATORY COMfilSSI0fl 0FFICE OF IllSPECTI0ft ATID EllFORCEMEllT UASHIflGT0fl, D.C. 20555 i
l August 27, 1980 I
IE Information f!otice fio. 80-31: f1ALOPERATION OF GOULD-BROWN B0 VERI 480 i
VOLT-TYPE K-6005 AND K-DON 600S CIRCUIT i
BREAKERS Descrintion of Circumstances:
The Cincinnati Gas & Electric Company reported problems with the Gould-Brown Boveri Type K-600S and K-DGft 600S circuit breakers used in 480 volt a.c.
circuits at the William H. Zimmer nuclear stations.
The problem involved inadvertent circuit breaker closure during operation of the breaker charging springs when the breaker was racked out to the test position.
~
l The problem resulted from the use of undersized bushings in the circuit breaker secondary close latches. The undersized bushings caused the secondary close latch to hang-up on tne shunt trip device resulting in an inadvertent circuit breaker closure when the spring charging motor was energized.
The vendor has stated that the problem does not exist during normal operations with the circuit breaker in the connected position.
Rec mmended Action for Licensees and Holders of Construction Permits:
All licensees of operating nuclear power rear. tors and holders of construction permits should be aware of the potential problems described above.
The vendor has stated that a small number of circuit breakers were assembled with under-sized secondary latch bushings between 1969 and 1977.
It is recommended that the following actions be taken:
(1) Determine if the subject circuit breakers are installed in any safety-related application at your facility.
The affected circuit breakers are manufactured by Gould-Brown Boveri and are types K-600S and K-DON 600S, 480-volt a.c. electrically operated, drawout type with static trip device.
(2)
If it is determined that your facility has the circuit breakers described in Item ) above, perform the K-600S, K-DON 600S Field Test Procedure a ttacht to this information notice (Gould-Brown Boveri I.B.-9.1.7-6 Issue I, Addendum 2, dated fiarch 4, 1980).
(3)
If maloperation of the circui field test procedure describe DUPLICATE DOCUMENT action described in the attac 0.050 shim to the secondary c Entire document previously entered into system under:
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