ML17254A890
| ML17254A890 | |
| Person / Time | |
|---|---|
| Site: | Ginna  |
| Issue date: | 06/26/1984 |
| From: | ROCHESTER GAS & ELECTRIC CORP. |
| To: | |
| Shared Package | |
| ML17254A889 | List: |
| References | |
| NUDOCS 8408070526 | |
| Download: ML17254A890 (8) | |
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June 26, 1984 Startup Physics Testing Program Cycle 14 Startup Physics Testing Program was conducted during the period from May 11, 1984 to June 88, 1984. The stated dates span from initial criticality to attainment of 188% power.
The results of the physics testing program showed that all measured data was within the bounds of the acceptance criteria tolerances with exceptions as noted below. The PT-34 series of procedures was used to perform the low power physics testing measurements in conjunction with the S-15 series for fluxmapping.
The program consisted of determining the following parameters:
- l. All rods out critical boron concentration
- 2. Isothermal Temperature coefficient
- 3. Control Rod Worths for Banks "D", "C" and "B"
- 4. Boron endpoints
- 5. Core symmetry and power distribution measurements
- 6. Critical boron concentration Full Power Initial criticality was achieved on 85/12/84 at 8458 hours0.0979 days <br />2.349 hours <br />0.014 weeks <br />0.00322 months <br />.
The Hot Zero Power parameters as listed in 1 thru 4 above were then measured. The flux symmetry mapping and subsequent power escalation and measurement of power distribution and hot channel factors was delayed until 5/23/84 due to the plant return to cold shutdown for secondary chemistry concerns. The following data summarizes the results of the testing program.
Critical Measurements a ~ Nuclear t Determination: Nuclear heat was observed at 4 x
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H~e 18 amps on Channel N-41. It was determined from this that alL reactivity measurements would be performed below 2 x 18 Full Scale amps to stay below nuclear heat.
- b. Reactiv~it Computer Checkout: The reactor was placed on varying periods to provide a comparison of indicated reactivity with that derived from period measurements. The following table summarizes the computer checkout:
Control BankT Measured 1 Reactivity (PCM) Tt Difference D Steps I Reactor I l(M-P) x 188 Withdrawn IPeriod/SecondslMeasured (M)IPredicted (P)l P 6
18 268 '3 157.2 23.16 35.S6 23 45
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.665 26 98 '5 52.52 53.1 -1.11%
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qc ~ 'Isothermal Temp ature Coe fficient: Heat p and cooldown rates of approximately 18 P7hr . were established to determine the isothermal temperature coefficient. The following data summarizes the results of the average of two acceptable traces.
Core ~ MTC ConfigurationIPredicted (P)I Criteria TAcce p tance I MTC I Difference IMeasured (M)I (M-P) s
-4.9 1 l r +2.685 ARO INot PositiveI -2.215 I I NOTE: Moderator Temperature Coefficient = ITC (-1.66)
- d. Control Rod Worth: Control Rod worth was measured by adjusting rod position to compensate for dilution. The following table summarizes the integral rod worth data.
Predict Measured Difference Ctrl I (P) (M) I Accept. I (M-P) x 188 I PredictI MeasureI Diff BankI (PCM) (PCM) ICriter. P PPM PPM IM-P 946 914.5 + 182 123 +21
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C 1842 1882 995.5 827.5
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-17.42 114 183 183 98
-ll5 Sum 2998 2737.5 + 18% 8.44 319 324 + 5 Acceptance Criteria: The acceptance criteria is that the measured individual bank integral worth be within 15% of the predicted values and that the total worth of three banks be within 185 of the predicted value. If the criterion on individual bank worth is not met, an evaluation will be performed to determine the cause and any potential impacts. If the criterion in total worth of the three banks is not met, additional banks will be measured until the measurement is within 18% of the prediction.
This will be continued, if necessary, to measurement at an N-1 rod inserted condition. The result of an N-l measurement, with appropriate allowance for measurement uncertainty, will be compared to the value assumed in the Safety Analyses.
As summarized above, Bank "B" indicated a deviation of predicted rod worth that exceeded the acceptance criteria of
+ 15%. The total rod worth for the three banks however, did satisfy the acceptance criteria of + 18'
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'The deviation ha been evaluated by nuclear 'engineering, and, it has been determined that proceeding to f ull power is acceptable for the following reasons.
The total rod worth for the three banks measured is within + 18% of predicted values, therefore, satisfying the assumptions outlined in the shutdown margin calcu-lation.
2 ~ The shutdown margin calculation (Table 6.3 of the Nuclear Design Report) indicates that excess shutdown margin of 818 pcm exists to the required shutdown margin of 1888 pcm at BOL.
3 ~ The measured ARO, D, D+C and, estimated D+C+B boron endpoint data compare well to the predicted values indicating that the B bank deviation does not represent an unanticipated core reactivity anomaly.
The Westinghouse nuclear designer is conducting his own evaluation to determine the cause of the deviation. Based on this evaluation, additional fluxmap data and comparison of overall core per formance versus predicted through the cycle, be determined at a later date whether to impose a higher D bank it can insertion limit toward end of cycle where the shutdown margin is at the minimum.
Con~icauration r(predicated r T Difference (p)(acceptance(Measured (M)( (M-p)
ARO 1329 + 75 1329 8 D Inserted 1227 + 75 1286 -21 D+C Inserted 1113 + 75. 1183 -18
- D+C+B Insertedl 1818 + 75 1885 5 Acceptance Criteria: The average critical boron concentration for a given configuration will be compared to the predicted concentration for that configuration. The acceptance criterion will be +75 ppm. If this acceptance criterion is not met, the measurement data will be reviewed and the fuel supplier will be asked to review his predictions. Concurrent with this review the remainder of the zero power physics testing will be completed to see if any other differences are present that could aid in determining the cause of not meeting the acceptance criteria.
If after the above actions, the acceptance criterion still cannot be met an evaluation will be performed on the effect of this difference on parameters used in the accident analysis'f the accident analysis is unaffected by this difference, the core will be allowed to go above 5% rated power.
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.~NOTE: Although the testing program did not specify measurement of Control Bank "B" PPM Boron North or the Boron Endpoint for D+C+B Inserted, suf ficient acquired boron sample data existed to include the stated value with reasonable confidence.
Flux Symmetry and Power Distribution: The flux symmetry fluxmap was performed at 23.6% rated power. All locations were evaluated to the acceptance criteria as listed below.
The only locations to fall out of the acceptance bounds, were locations I-5 and I-6, which recorded -14.231% and
-14.233% respectively. The thimble used to predict these locations is I-5. This specific assembly location is a Mixed Oxide Assembly (Plutonium enriched). The results were evaluated and it was determined that modeling of the power distribution for this assembly was the reason for the difference. The remainder of the map was in good agreement with predictions and verified the core was properly loaded.
All Nuclear Hot Channel factors were well within the bounds of Plant Technical Specifications.
During subsequent power escalation, fluxmaps were generated at 46$ , 71.5% with Incore/Excore calibration performed at 83% power. Following a reactor/turbine trip due to an exciter failure, power escalation to 188% was achieved.
The 188% map was then taken on 6/8/84, with all Hot Channel Factors well within the bounds of Plant Technical Specifi-cations.
A~cce tance Criteria: The acceptance criterion for a flux map is that the plant Technical Specification on peaking factors be met. As an aid in evaluating the power distribution maps, the differences between measured and predicted assembly power levels are reviewed. General criteria for these comparisons are that the difference for assemblies with relative power <1 '
be less than 15% and the difference for assemblies with relative power >1.8 be less than 18%. If these differences are exceeded, an evaluation shall be performed to ensure that the peaking factor Technical Specifications will be met. If such an evaluation indicates that the peaking factor limits will be met, no further action is necessary.
ge Critical Boron Concentration Full Power: Due to the numerous delays as a result of secondary concerns encountered during startup, Hot Full Power Steady state conditions were not attained until 6/8/84, which represents an exposure of "388 MWD/MTU. The calculated boron concentration at that point was 888 PPM with a predicated value of 828 PPM.
Subsequent Boron measurements to date indicate the predicated to closely approximate the actual values obtained.
RECElVEO-REGlON 1 l2 Plil l: 52
$ 85 JUL
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