ML18012A130

Proposed Tech Specs Incorporating Inspection Guidance from NRC Inspection Procedure 61706, Core Thermal Power Evaluation.

ML18012A130
Person / Time
Site:	Harris
Issue date:	02/08/1996
From:	CAROLINA POWER & LIGHT CO.
To:
Shared Package
ML18012A129	List: ML18012A128 ML18012A130
References
HNP-96-014, HNP-96-14, NUDOCS 9602130081
Download: ML18012A130 (2)

Text

POWER DISTRIBUTION LIMITS BASES HEAT FLUX HOT CHANNEL FACTOR AND RCS FLOW RATE AND NUCLEAR ENTHALPY RISE HOT CHANNEL FACTOR Continued limit on the hot channel factor, F~(Z), is met. V(Z) accounts for the effects of normal operation transients and was determined from expected power control maneuvers over the full range of burnup conditions in the core. The V(Z) function is specified in the COLR.

The core thermal power is determined by calorimetric on a daily frequency.

The safety analysis is performed at 102K RATED THERMAL POWER to account for calorimetric uncertainty. Thermal power is considered to be within the 100.0X RATED THERMAL POWER limit of Figure 3.2-3 provided:

a) average thermal power for any shift does not exceed 100K RATED THERMAL POWER, and b) instantaneous thermal power does not exceed 102K RATED THERMAL POWER, and c) average thermal power is less than 102K RATED THERMAL POWER for a fifteen minute period. or 101K RATED THERMAL POWER for a thirty minute period. or 100.5X RATED THERMAL POWER for a sixty minute pel 1 od.

When RCS flow rate is measured, no additional allowance is necessary prior to comparison with the limit of Specification 3.2.3. A normal RCS flowrate er ror of 2.1X will be included in C,, which will be modified as discussed below.

The measurement error for RCS total flow rate is based upon performing a precision heat balance and using the result to calibrate the RCS flow rate indicators. Potential fouling of the feedwater venturi which might not be detected could bias the result from the precision heat balance in a non-conservative manner. Therefore, a penalty of 0.1X for undetected fouling of the feedwater venturi. raises the nominal flow measurement allowance, C,. to 2.2X for no venturi fouling. Any fouling which might bias the RCS flow rate measurement greater than 0. 1X can be detected by monitoring and trending various plant performance parameters. If detected. action shall be taken before performing subsequent precision heat balance measurements, i.e., either the effect of the fouling shall be quantified and compensated for in the RCS flow rate measurement or the venturi shall be cleaned to eliminate the fouling.

The upper limit on measured RCS flow rate in Figure 3.2-3

[321,300 gpm x (1.0 - C,)j protects the mechanical design flow of 321,300 gpm per FSAR Table 5.1.0-1.

The 12-hour periodic surveillance of indicated RCS flow is sufficient to detect only flow degradation that could lead to operation outside the acceptable region of operation.

SHEARON HARRIS - UNIT 1 B 3/4 2-5 HNP-96-014 February 8, 1996 vsoaisooaz ~soaos PDR ADQCK 05000400 P PDR

POWER DISTRIBUTION LIMITS BASES 3/4.2.4 UADRANT POWER TILT RATIO The QUADRANT POWER TILT RATIO limit assures that the radial power distribution satisfies the design values used in the power capability analysis. Radial power distribution measurements are made during STARTUP testing and periodically during power operation.

The limit of 1.02, at which corrective action is required, provides DNB and linear heat generation rate protection with x-y plane power tilts. A limiting tilt of 1.025 can be tolerated before the margin for uncertainty in F is depleted. A limit of 1.02 was selected to provide an allowance for t5e uncertainty associated with the indicated power tilt.

The 2-hour time allowance for operation with a tilt condition greater than 1.02 but less than 1.09 is provided to allow identification and correction of a dropped or misaligned control rod. In the event such action does not correct the tilt. the margin for uncertainty on F, is reinstated by reducing the maximum allowed power by 3X for each percent of tilt in excess of 1.

For purposes of monitoring QUADRANT POWER TILT RATIO when one excore detector is inoperable, the movable incore detectors are used to confirm that the normalized symmetric power distribution is consistent with the QUADRANT POWER TILT RATIO. The incore detector monitoring is done with a full incore*flux map or two sets of four symmetric thimbles. The preferred sets of four symmetric thimbles is a unique set of eight detector locations. These locations are C-8, E-5. E-ll, H-3, H-13. L-5, L-11. N-8. If other locations must be used, a special report to NRC should be submitted within 30 days in accordance with 10CFR50.4.

3/4.2.5 DNB PARAMETERS The limits on the DNB-related parameters assure that each of the parameters are maintained within the normal steady-state envelope of operation assumed in the transient and accident analyses. The limits are consistent with the initial FSAR assumptions and have been analytically demonstrated adequate to maintain a minimum DNBR that is equal to or greater than the design DNBR value throughout each analyzed transient. The indicated T , value and the indicated pressurizer pressure value are compared to analyticaT limits of 586. 1'F and 2185 psig, respectively, after an allowance for measurement uncertainty is included.

The 12-hour periodic surveillance of these parameters through instrument read-out is sufficient to ensur e that the parameters are restored within their limits following load changes and other expected transient operation.

SHEARON HARRIS - UNIT 1 B 3/4 2-6 HNP-96-014 February 8, 1996