ML20107L760

Ro:On 960404,spurious Safety Channel 2 Loss of High Voltage Trip Occurred.Caused by Previously Undetected Matl Failure. Repairs Should Be Completed by 960410 & Restart Approved Subject to Successful post-repair Checks

ML20107L760
Person / Time
Site:	05000083
Issue date:	04/05/1996
From:	Vernetson W FLORIDA, UNIV. OF, GAINESVILLE, FL
To:	Ebneter S NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
Shared Package
ML20107L750	List: ML20107L748 ML20107L760
References
NUDOCS 9604300014
Download: ML20107L760 (1)

Text

. -. i t

ATTACIBIENT I

. DNIVERSITY OF

- @. ' FLORIDA .

l College of Engineering P. O. Box 118300 Department of Nuclear Engineering Sciences 202 Nuclear Sciences Center l Gainesville, Florida 326118300 l Tel: (352) 392-1401 Fax: (352) 392-3380 E-Mail: nuceng@ pine.circa.ufl.edu April 5,1996 U.S. Nuclear Regulatory Commission _ _

Region U 101 Marietta Street, N.W., Suite 2900 Potential Tech Spec Violation -

Atlanta, GA 30323 Failure in Safety Channel 2 High Voltage Circuit Attention: Stewart Ebneter, Regional Administrator l

Re: University of Florida Training Reactor Facility License: R-56, Docket No. 50-83 As per the telephone con ~versation'of April 5,1996 with Mr. Al Gooden relative to a failure of resistors' l 1

in safety channel 2 high voltage circuit discovered on April 5,1996, we have concluded this occurrence is a potential abnormal occurrence and a potentially reportable occurrence per UFTR Technical Specifications, Section 6.6.2 delineating requirements for special reports. The RSRS Executive Committee has met and in agreement with UFTR management has recommended NRC notification as per Section 6.6.2 of the UFTR Tech Specs as a potentially promptly reportable occurrence. Initial evaluation indicates l l that the required scram on 10% reduction of safety channel 2 high voltage was potentially set somewhat l above 10% due to a material failure in two resistors. The problem apparently occurred sometime after l the last quarterly scram checks were conducted on January 26,1996 and before the latest ones were conducted on March 27, 1996. The actual problem was corrected on March 27, 1996 by a slight adjustment; however, the cause was not discovered until troubleshooting was completed on April 5,1996 following a spurious safety channel 2 loss of high voltage trip on April 4,1996 caused by the previously ,

undetected material failure. Repairs should be completed by April 10,1996 and the RSRS executive l j committee has approved restart subject to successful post-repair checks.

l- Sincerely, e

l 9604300014 960425

! PDR ADOCK 05000083 Wilh.am G. Vernetson l l S PDR Director of Nuclear Facilities WGV/cb copies: D. Simpkins RSRS Sworn and subscribed this % day of April,1996.

KAmLEEN A. WILSON l

, l MLtn b . Mc.n $$7 7 8'"*' """ W

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Notary Public l

l Equal Opportunity /AfGrrnative Action Institution