ML17319A832

Proposed Tech Specs 3/4.2 Re Power Distribution Limits Axial Flux Difference

ML17319A832
Person / Time
Site:	Cook
Issue date:	05/01/1981
From:	INDIANA MICHIGAN POWER CO. (FORMERLY INDIANA & MICHIG
To:
Shared Package
ML17319A831	List: ML17319A830 ML17319A832
References
NUDOCS 8105070176
Download: ML17319A832 (11)

Text

3/4.2 POWER DISTRIBUTION L IM ITS AXIAL FLUX DIFFERENCE (AFD LIMITING CONDITION FOR OPERATION 3.2.1 The indicated AXIAL FLUX DIFFERENCE (AFD) shall be maintained within a

+55 target band (flux difference units) about the target flux difference.

APPLICABILITY: MODE 1 ABOVE 50K RATED THERMAL POWER*

I ACTION:

a. With the indicated AXIAL FLUX DIFFERENCE outside of the +5 ~

,target band about the target flux difference and with THERMAL POWER:

l. Above 81/ of RATED THERMAL POWER, within 15 minutes:

a) Either restore the indicated AFD to within the target band limits, or b) Reduce THERMAL= POWER to less than 815 of RATED THERMAL POWER.

2. Between 50'. and 81 /. of RATED THERMAL POWER:

a) POWER OPERATION may continue provided:

1) The indicated AFD has not been outside of the

+5/ target band for more than 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> penalty deviation cumulative during the previous 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, and

2) The indicated AFD is within the limits shown on Figure 3. 2-1. 0therwi se, reduce THERMAL POWER to less than 505 of RATED THERMAL POWER within 30 minutes and reduce the Power Range Neutron Flux-High Trip Setpoints to < 555 of RATED THERMAL POWER within the next 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />.

b) Surveillance testing of the Power Range Neuter on Flux Channels may be performed pursuant to Specification 4.3.1.1.1 provided the indicated AFD is maintained within the limits of Figure 3.2-1. A total of 16 hours1.851852e-4 days <br />0.00444 hours <br />2.645503e-5 weeks <br />6.088e-6 months <br /> operation may be accumulated with the AFD out-side of the target band during this testing without penal ty devia tion.

I I .I .I D. C. COOK - UNIT 2 3/4 2-1

OWER DISTRIBUTION LIMITS C CTIOH: (Continued) c) Surveillance. testing of the APDMS may be performed pursuant to Specification 4.3.3.7.1 provided the indicated AFD is maintained within the limits of Figure 3.2-1. A total of 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> of operation may accumulated with the AFD outside of the'target

'e band duri ng this testing without penalty deviation.

b. THERMAL POWER shall not be increased above 81Ã of RATED THERMAL POWER unless the indicated AFD is within the +5K target band and,ACTION 2.a) 1), above has been satisfied.

'c. THERMAl POWER shall not be increased above 50% of RATED THERMAL POWER unless the indicated AFD has not been outside of the

+5'arget band for. more than 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> penalty deviation cumulative during the previous 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

SURVEILLANCE RE UIREMEHTS C

4.2;1.1 The indicated AXIAL FLUX DIFFERENCE shall be determined to be within its limits during POWER OPERATION above 15K of RATED THERMAL POWER by:

a. Monitoring the indicated AFO for each OPERABLE excore channel:

At least once per 7 days when the AFD Monitor Alarm is OPERABLE, and

2. At least once per hour for the first 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> after restoring the AFD Monitor A'larm to OPERABLE status.

b. Monitoring and logging the indicated AXIAL FLUX DIFFERENCE for each OPERABLE excore channel at least once per hour for the first, 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> and at least once per 30 minutes thereafter, when the AXIAL FLUX DIFFERENCE Monitor Alarm is inoperable.

The logged values of the indicated AXIAL FLUX DIFFERENCE shall be assumed, to exist during the interval preceding each logging.

D. C. COOK '- UNIT 2 3/4 2-2

Unacceptable Unacceptable Operation Oper ation Acceptab'I e 60 0 per tion

(-2s,so) ~ (25,50) 40 20 0

-50 -40 - 30 . -20 - IO 0 10 .20 30 '0 50 FLUX DIFFERENCE {bl) %

FIGURE 3.2-1 AXIALFLUX DIFFERENCE LIMITS AS A FUNCTION OF RATED THERMAL POWER O. C. COOK' UNIT 2 3/4 2-4

(L POWER DISTRIBUTION LIMITS AXIAL POWER DIS1RIBUTION LIMITING COflDITION FOR OPERATION 3.2.6 The axial power distribution shall be 'limited by the following-relationship:

1.99 V, Z CF (Z)] =

{R .)(PL)(1.03){1 + a ){1.07)

Where:

a. is the norma lized axial distribution from thimble F

j.(Z) power j at core elevation Z.

b. PL is the fraction of RATED THERMAL POWER.

c. K{Z) is the function obtained from Figure 3.2-2 for a given core height location'.

R., for thimble j, is determined from at least n=6 in-core flux maps. covering the full configuration of permissib'le rod patterns above 91! of RATED THERMAL POWER in accordance with: I n

R. = ~ R..

j n ~

1 ij Where:

R..=

ij ~ij Z~>iax and [F..

1J (Z)]f< t fax is the maximum value'of the normalized axial distribution at elevation Z from thimble j in map i which had a measured peaking factor without uncertainties or densification allowance of F~Meas

0. C. COOK - UfllT 2 3/zl 2-17 Amendment No. 17

~ 'OWER DISTRIBUTION LIMITS LIMITING COND I I ION FOR OPERATION Continued

o. is the standard deviation associated with thimble j, expressed as a fraction or percentage of R., and is derived from n flux maps from the relationship below, or 0.02, (2X) whichever is greater.

o =

f ~(R -R.) ]

, R.

The factor 1.07 is comprised of 1.02 and 1.05 to account for the axial power distribution instrumentation accuracy and the measure-ment uncertainty associated with F using the movable detector system respectively.

The factor 1.03 is the engineering uncertainty factor.

APPLICABILITY: MODE 1 above 91/ OF RATED THERMAL POWER .

. ACTION;

a. With a F (Z), factor exceeding [F.(Z)]

j S by < 4 percent, reduce J

THERMAL POWER one percent for every percent by which the F.(Z) factor exceeds its limit within 15 minutes and within the next two hours either reduce the F.(Z) factor to within its limit J

or reduce THERMAL POWER to Slà or less of RATED THERMAL POWER.

b. With a F.(Z) factor exceeding [F-(Z)]S J

by > 4 percent, reduce J

THERMAL POWER to 915 or less of RATED THERMAL POWER within 15 minutes.

à The APDHS may be out of service when surveillance for determini ng power'istribution maps is being performed.

D. C. COOK - UNIT 2 3/4 2-18

POWER DISTRIBUTION LIMITS SURVEILLANCE RE UIREMENTS 4.2.6.1 F.(Z) shall be determined to be within its limit by:

J a'. Either using the APDMS to monitor the thimbles required per Specification 3.3.3.6 at the following frequencies.

1. At least once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />, and

2. Immediately and at intervals of 10, 30, 60, 90, 120, 240 C

and.480 minutes following:

a)'Increasing the THERMAL POWER above 91K of RATED THERMAL POWER, or b) Movement of control bank "D" more than an accumulated total of 5 steps in any one direction.

b. Or using the movable incore detectors at the following fre-quencies when the APDMS is inoperable:

l. At least once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />, and

2. At intervals of 30, 60, 90, 120, 240 and 480 minutes following:

a) Increasing the THERMAL POWER above 91Ã of RATED THERMAL POWER, or b) Movement of control bank "0" more than an accumulated total of 5 steps in any one direction.

4 .2.6.2 When the movable incore detectors are used to moni tor F .(Z),

J at least 2 thimbles shall be monitored and an F.(Z) accuracy equivalent J

to that obtained from the APDMS shall be maintained.

D. C. COOK - UNIT 2 3/4 2-19 II f '

I

~ ~

POWER DISTRIBUTION LIMITS BASES Although it is intended that the plant will be operated with the AXIAL FLUX DIFFERENCE within the +5" target band about the target flux difference, during rapid plant THERIQL POWER reductions, control rod motion will cause the AFD to deviate outside of the tar get band at re-duced THERMAL POWER levels. This deviation will not affect the xenon redistribution sufficiently to change the envelope of peaking factors which may be reached on a subsequent return to RATED THERMAL POWER (with the AFD within the target band) provided the time duration of the devi-ation is limited. 'ccordingly, a 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> penalty deviation limit cumu-lative during the previous 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> is provided or operation outside of the target band but within the limits of Figure 3.2-1 while at THERtlAL POWER levels between 50% and 81% of RATED THERtQL POWER. For THERIQL POWER levels between 15% and 50% of RATED THERHAL POWER, deviations of the AFD outside of the target band are less significant. The penalty of 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> actual time reflects this reduced significance.

Provisions for monitoring the AFD on. an. automatic basis are derived from the plant process computer through the AFD Monitor Alarm. The computer determines the one minute average of each of the OPERABLE excore detector outputs and provides an alarm message immediately i the AFD for at least 2 of 4 or 2 of 3 OPERABLE excore channels are outside the target band and the THERI)AL" POWER is gr eater than 81% of RATED THERMAL PO'WER. During operation at THERMAL POWER levels between SOll and 81% and between,15,. and 50% RATED THEfNAL POWER, the computer outputs an alarm message when the penalty deviation accumulat'es beyond the limits of 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> and 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />, respectively.

Figure B 3/4 2-1 shows a typical monthly target band.

D.C. COOK - UNIT 2 B-3/4 2-2

5 4 g

ATTACHMENT No. 2 to AEP:NRC:0564 A modification was made to the high pressure turbine in Unit 2 during the current refueling outage to improve overall turbine efficiency.

The current Technical Specification setpoint for the P-7 permissive in the logic of the Reactor Protection System (RPS) is low and needs to be increased to the new value of the first stage turbine impulse chamber pressure corresponding to 10/,'power (66 psia). Our calculations indicate that the current P-7 setpoint may cause unnecessary tripping of the reactor since Reactor Trip from a Turbine Trip could occur during the turbine overspeed tests with the current (low) setpoint of the impulse chamber pressure. Raising, the setpoint of the P-7 permissive to 66 psia will I

avoid possible unnecessary reactor trips, is consistent with the FSAR value for Reactor Trip/Turbine Trip at o) above 10$ power, and will not adversely affect the health and safety of the public.

The proposed revision is indicated on the attached page by a vertical line in the right margin.

TABLE 3. 3-1 Continued DESIGNATION CONDITION AND SETPOINT FUNCTION P-7 With 2 of 4 Power Range Neutron P-7 prevents or defeats Flux Channels > 11% of RATED the automatic block of THERMAL POWER or 1 of 2 Turbine reactor trip on: Low impulse chamber pressure channels flow in more than one

> 66 psia. primary coolant loop, reactor coolant pump under-voltage and under-frequency, turbine trip,

'pressurizer low pressure, and pressurizer high level.

P-8 With 2 of 4 Power Range Neutron P-8 prevents or defeats Flux channels > 51% of RATED .the automatic block of THERMAL POWER. reactor trip on low coolant flow in a single loop.

P-10 With 3 of 4 Power range neutron P-10 prevents or defeats flux channels ( 9% of RATED the manual block of: Power THERMAL POWER. range low setpoint reactor trip, Intermediate range reactor trip, and intermediate range rod stops.

Provides input to P-7.

D. C. COOK - UNIT 2 3/4 3-8

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