ML20064C106
| ML20064C106 | |
| Person / Time | |
|---|---|
| Site: | Sequoyah  |
| Issue date: | 12/29/1982 |
| From: | Mills L TENNESSEE VALLEY AUTHORITY |
| To: | Adensam E Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 8301040316 | |
| Download: ML20064C106 (2) | |
Text
__
e e
.e TENNESSEE VdLLEt AUTHORITY CH ATTANOOG A, TENNESSEC 374o1 400 Chestnut Street Tower II December 29, 1982 Director of Nuclear Reactor Regulation Attention:
Ms. E. Adensam, Chief Licensing Branch No. 4 Division of Licensing U.S. Nuclear Regulatory Commission Washington, D.C.
20555
Dear Ms. Adensam:
In the Matter of
)
Docket No.
50-327 Tennessee Valley Authority
)
50-328 As requested by Melanie Miller of your staff, we are providing a revised response to an NEC verbal question and request for additional information.
The enclosure provides the revised response to the question concerning change No. 3 of TVA-SQN-TS-36, Proposed Change in the Instrumentation Surveillance Requirement Test Frequency of Tables 4.3-1 and 4.3-2.
If you have any questions concerning this matter, please get in touch with J. E. Wills at FTS 858-2682.
Very truly yours, TENNESSEE VALLEY AUTHORITY L. M. Mills, Manager Nuclear Licensing i
Sworn d subscr ea before me this
' day of 1982
(
Notary Public g
My Commission Expires 7 h i
Enclosure cc:
U.S. Nuclear Regulatory Commission (Enclosure)
Region II Attn:
Mr. James P. O'Reilly Administrator 101 Marietta Street, Suite 3100 Atlanta, Georgia 30303 307/
8301040316 821229 PDR ADOCK 05000327 P
PDR l
., n o e n c.
a, t.
+
4
3
.s r
a-w$
s
~
an.vy)
. ~
~-
ENCLOSURE 1
-C d
- P
.y
,?
NRC Question e
/
s,.'
Did TVA evaluate the calibration data for trends?
JV' 5:
TVA Response
/
[.[
2 Recalibration of the SSPS bistables at Sequoy'ah is not'perforr/d unless the b"
j setpoint has drifted more than 50 perc'ent.of the tole.1ance-values.. The 1
tolerance values are specified to be 2.S' perdent of tt:e instrudsent span.
The drift allowed by technical specifications, defined ss the differerne v
r between the trip setpoint and the allowable valus is 1 1 percent.
." /)
7"'
, C ~,b. ;
/
Reviewofplantfunctionaltest.datapackagssjindicgtedthaton%3aemqll
/
fraction of the bistables tested even exceeded the r=.25 percer.t recalibra-
'J,@
tion criteria during the one-year period th2t yas evaluated. None exceeded i
the specified tolerance or tech spec valuc,5/ $ Th'e data shows Atg bistables to be extremely stable. Drift, where measurd, was random,iirjnatuje and no drift pattern (high or low) was indicated. The magnitude of,the observed monthly drift was small, typically much smaller than 0.25. percent. The
~
total bistable setpoint drift for any three-month period, d,uring the one-year period that was evaluated,'did not exceed the 1 percent allowed by,
the technical s?ecifications.
9
/
~
r J
1 i
/
/ '
. s, ; *..
r*
p=
ryf~'
,e t
/;
o,f 1.-
j
's L
~
s t
)
4
,an
-l sp * ~ ? S l'
o J
s 5
8 g
f'?
g d
)
1 '
r
, i
[
4 g.
s' 1
e
- w
,=
^
t
,r x
f
,o a
r o
~,
/
'W-
- /
l
}
m
/i
- - _.,