ML20035D090
| ML20035D090 | |
| Person / Time | |
|---|---|
| Site: | University of Michigan |
| Issue date: | 04/06/1993 |
| From: | Fleming R MICHIGAN, UNIV. OF, ANN ARBOR, MI |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| 17, NUDOCS 9304120129 | |
| Download: ML20035D090 (2) | |
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i Nuclear Reactor Laboratory l
'a The University of Michigan Ford Nuclear Reactor Phoenix Memorial Laboratory 2301 Bonisteel Boulevard i
I April 6, 1993 Docket 50-2 License R-28 United States Nuclear Regulatory Commission Attn: Document Control Desk Washington, D.C.
20555 Reportable Occurrence No. 17 Operation of the Ford Reactor at 2.3 Hw for Between 10 and 11 Minutes Centlemen:
This letter is Reportable Occurrence No. 17, operation of the Ford Nuclear Reactor at 2.3 Mw for between 10 and 11 minutes. The event occurred in the morning of March 24, 1993, following a calorimetric l
power level determination.
1 Sequence of Events On Wednesday, March 24, 1993, during the startup, calorimetric power level determination, and escalation to full power at the beginning i
of a ten-day operating cycle, power was increased to 2.3 Mw.
The shift crew had completed a routine reactor checkout and startup to an indicated reactor power of 100% on the Linear Level system 1 Mw range.
The reactor was in automatic control with the control system setpoint at 100%.
A calorimetric determination of reactor power was conducted utilizing Operating Procedure 106, Power Level Determination.
Actual thermal power was determined to be 1.156 Mw.
At this point, the shift crew should have reduced the automatic control system setpoint and Linear Level indication to 86%
(100%*[1.0/1.156]) to reduce thermal power to 1 Mw.
At 0705, the Shift Supervisor directed power to be raised i
to an indicated power to 2 Mw (100% on the 2 Mw Linear Level range).
When indicated power reached 2 Mw, actual thermal power was 2.3 Mw.
At approximately 0715, the Assistant Reactor Manager for Operations arrived.
After a review of the calorimeter data, he immediately ordered the reactor to be returned to 1 Mw indicated power.
At 1 Mw, corrective actions were taken to adjust indicated power on the neutron measurement channels to actual thermal power.
1 9304120129 930406 PDR S
ADDCK 05000002 l @)-
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Report.able Occurrence No. 17 United States Nuclear Regulatory Commission
)
April 6,
1993 i
Corrective Act. ion Operating Procedure 106 has been modified and retitled, power Level Determination and Increase to Full Power.
Dry runs have been conducted by the three shift crews.
The modifications were approved by the Safety Review Committee on April G,
1993, and the procedure will be utilized during the routine reactor startup on April 7,
1993, under the supervision of reactor management.
The revised procedure specifically requires that the automatic control syst em setpoint be adjusted to 1 Mw before going to full power, and that neutron detection chambers be adjusted to within their prescribed ranges at 1 Mw, if chamber adjustments are necessary.
A review of the calorimetric power level determination and chamber adjustments must be conducted by reactor management before power is increased to 2 Mw.
The s e n i c> r reactor operator who was the Shift Supervisor on the shift crew has been removed from all licensed dutles.
Sincerely.
[
Ronald F.
Fleming
/
Director
/
xe:
Dr ki11iam C.
Eelly, Vice president for Research Safety Review Committee Members Reactor Operations Staff United States Nuclear Re g u l a t o r.v Commission Attn: Charles Norelius 799 Roosevelt Road Glen Ellyn, Illinoic. 60137 l
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