ML20134P739

RO 85-1:on 850108,fuel Temp Recorder Indicated 600 F Instead of 720 F.Caused by Failure of Reactor Safety Sys Channel. Faulty Slide Wire & Contact Arm Replaced

ML20134P739
Person / Time
Site:	05000128
Issue date:	01/10/1985
From:	Rogers D TEXAS A&M UNIV., COLLEGE STATION, TX
To:	Johnson E NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
References
RO-85-1, NUDOCS 8509090037
Download: ML20134P739 (2)

Text

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. Dm6 l TEXAS ENGINEERING EXPElllM ENT STATION THE TEXAS A&M UNIVERSITY SYSTEM COLLEGE STATION, TEXAS 77843-3575 #

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10 January 1985 -

NUCLEAR SCIENCF CENTER 409/845-7551 Mr. E. Johnson Office of Inspection and Enforcement a DUM  %'

Region IV

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I U.S. Nuclear Regulatory Commission A lSl%5 i n xa b12 J l

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Dear Mr. Johnson:

I am forwarding the final report of the reportable occurrence of 8 January 1985. This report is being submitted in accordance with NSC Technical Specifi-cation Section 6.6.2 for License R-83, Texas A&M University.

Respectfully, il t ,%

Dale Rogers b Assistant Director DR/ym Enclosure I

1 8509090037 850110 hDR ADOCK 05000128 eDe y

RESEARCH AND DEVELOPMENT FOR MANKIND 1

Reportable Occurrence #85-1 Failure of Reactor Safety System Channel (Fuel Temperature Instrument) During Reactor Operation REPORTABLE OCCURRENCE On 8 January 1985 at 1038 the reactor operator observed that the fuel temperature recorder indicated approximately 600 F which did not agree with the normal 1 Mw temperature of approximately 720*F. Reactor power had just been lowered to position a sample and upon returning to 1 Mw at 1033 the fuel temperature recorder stuck. A check of other digital temperature indications l' and reactor power verified that the reactor was indeed at 1 Mw. At 1040 l

during investigation the operator touched the slidewire contact arm in the ,

! recorder and the reading returned to normal. Over the next fifteen minutes the reactor power was lowered and returned to 1 Mw several times to observe the temperature recorder response and no problems were noted. The reactor i was shutdown at 1058 for further investigation.

CORRECTIVE ACTION Fuel temperature responded normally on the recorder during the reactor shutdown. The slidewire assembly was inspected and the contact arm points i appeared to be worn. The slidewire and contact arm were replaced and the l fuel temperature instrument semi-annual maintenance was completed satisfactorily. The reactor was started up and returned to power at 1206.

! The recorder response was normal and no further problems were noted.

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