ML20245B913
| ML20245B913 | |
| Person / Time | |
|---|---|
| Site: | Sequoyah  |
| Issue date: | 04/19/1989 |
| From: | NRC |
| To: | |
| Shared Package | |
| ML20245B915 | List: |
| References | |
| NUDOCS 8904260368 | |
| Download: ML20245B913 (2) | |
Text
_ _ _ _ _ _
o S j
.c POWER DISTRIBUTION LIMITS SURVEILLANCE REQUIREMENTS (Continued) 1 4.2.2.2 F (z)'shall be evaluated to determine if F (Z) is within its limit q
q by:
a.
Using the movable incore detectors to obtain a power distribution map at any THERMAL POWER greater than 5% of RATED THERMAL POWER.
b.
Increasing the measured F (z) component of the power distribution 9
map by 3 percent to account for manufacturing tolerances and further increasing the value by 5% to account for. measurement uncertainties.
c.
Satisfying the following relationship:
F (z) 5 2.237 x K(z) for P > 0.5 P x W(z)
F (z) 1 2.237 x K(z) for P i 0.5 W(z) x 0.5 where F (z) is measured F (z) increased by the allowances for q
manufacturing tolerances and measurement uncertainty, F limit is q
the F limit, K(z) is given in Figure 3.2-2, P is the relative q
THERMAL POWER, and W(z) is the cycle dependent function that accounts for power distribution transients encountered during normal operation.
This function is given in the Peaking Factor Limit Report as per Specification 6.9.1.14.
d.
Measuring F (z) according to the following schedule:
1.
Upon achieving equilibrium conditions after exceeding by 10 percent or more of RATED THERMAL F0WER, the THERMAL POWER at which F (z) was last determined,* or q
l 2.
At least once per 31 effective full power days, whichever occurs first.
l
- During power escalation at the beginning of each cycle, power level may be increased until a power level for extended operation has been achieved and a power distribution map obtained.
- See Page 3/4 2-6a SEQUOYAH - UNIT 2 3/4 2-5 Amendment No. 21, 95 8904260368 890419 PDR ADOCK 05000328 i
P PDC t________._____
)
'I POWER DISTRIBUTION LIMITS SURVEILLANCE REQUIREMENTS (Continued)
-l e.
With measurements indicating g
maximum F (z) q over z K(z) has increased since the previous determination of F (z) either of the'following actions shall be taken:
1.
F (z) shall be increased by 2 percent over that specified in 4.2.2.2.c, or 2.
F (z) shall be measured at least once per 7 effective full power days until 2 successive maps indicate that i
maximum F"(z) is not increasing.
over z K(z) j f.
With the relationships specified in 4.2.2.2.c above not being satisfied:
1.
Calculate the percent F (z) exceeds its limit by the 9
following expression:
e
~
D M
F (z) x W(z) maximum g
-1p x 100 for P > 0.5 over z 2.237 x K(z)
)
P
,/
j w
(
M q
F (z) x W(z)
)
maximum 9
-1,x 100 for P < 0.5 f
over z 2.237# x K(z)
- 0. 5 J
2.
Either of the following actions shall be taken:
a.
Place the core in an equilibrium condition where the limit in 4.2.2.2.c is satisfied.
Power level may then be increased provided the AFD limits of Figure 3.2-1 are reduced 1% AFD for each percent F (z) exceeded its limit, or q
b.
Comply with the requirements of Specification 3.2.2 for F (z) exceeding its limit by the percent calculated 9
l above
- See page 3/4 2-6a.
SEQUOYAH - UNIT 2 3/4 2-6 Amendment No. 21, 95 a______-
_