ML20235V158
| ML20235V158 | |
| Person / Time | |
|---|---|
| Site: | Callaway  |
| Issue date: | 10/05/1987 |
| From: | Schnell D UNION ELECTRIC CO. |
| To: | NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM) |
| References | |
| ULNRC-1639, NUDOCS 8710150019 | |
| Download: ML20235V158 (3) | |
Text
TT This letter is being reissued to UNION correct the letter date -
Etscruic 2M33 1901 Gratiot Street. St. Louis Donald F. SchneII Vte Praident '
October 5, 1987 U.S. Nuclear ~ Regulatory Commission ATTN Document Control Desk Washington,.D.C. 20555 Gentlemen:
ULNRC-1639 DOCKET NUMBER 50-483 CALLAWAY PLANT AMSAC GENERIC _ DESIGN PACKAGE
References:
- 1. OG-87-35 dated 8/3/87, WCAP-10858-P-A,' Revision 1, "AMSAC Generic Design Package"
- 2. OG-87-10 dated 2/26/87, WCAP-10858-P-A, Addendum 1
- 3. ULNRC-1472 dated 3/19/87
- 4. ULNRC-1492 dated 4/15/87 This correspondence is based upon a telephone conversation
]
held on 10/2/87 between NRC, WCNOC, and UE personnel during which the implications of Reference 1 were discussed.
Reference 1 revised the AMSAC Generic Design Package to address the'following:
1.
Incorporation of Addendum 1 (Reference 2) which provided the basis for the AMSAC C-20 setpoint (40% power) and changed the low feedwater flow setpoint for Option 2.
The former is applicable to Callaway Plant, as discussed in References 3 and 4, whereas the latter is not j
applicable since we are implementing Option 1 based on steam generator water level.
2.
Addition of a variable time delay for Options 2 and 3, described on pages 4-8, 4-9, 5-9, and 5-10 of Reference 1.
This variable time delay is dependent upon turbine impulse chamber pressure and was added to minimize spurious actuations and to allow the reactor protection j
system to provide the first trip signal at reduced power i
levels.
This is required only for Options 2 and 3.
Option 1, which is based on a reactor trip variable, does not require this variable time delay as stated in Reference 4.
3.
Revision of the C-20 permissive signal delay from 120 seconds to 360 seconds.
The Callaway AMSAC design will incorporate this change which allows AMSAC to remain armed for 360 seconds to allow time to perform its h0]Og{ h D
. a e,,.
O S,,,.,,c.
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}
function in the event of a turbine trip.
This change is based on AMSAC signal delays at reduced power levels, as discussed in Reference 1.
-Therefore, the only change to the Callaway AMSAC design as a result of Reference 1 is the increase in the C-20 delay.
The C-i 20 setpoint at 40% of NSSS thermal power was previously included in our design, as discussed in References 3 and 4.
l If you have any further questions, please contact us.
Very truly yours, l
l' Donald F.
Schnell GGY/ lad 1
l l
l i
u
)..
t f-1 cc:
Gerald Charnoff, Esq.
I Shaw, Pittman, Potts & Trowbridge 2300 N. Street, N.W.
Washington, D.C.
20037 Dr. J. O. Cermak CFA, Inc.
1 4 Professional Drive (Suite 110) l Gaithersburg, MD 20879 j
\\
W. L.
Forne y Chief, Reactor Project Branch 1
)
U.S. Nuclear Regulatory Commission Region III 799 Roosevelt Road Glen Ellyn, Illinois 60137 Bruce Little i
Callaway Resident Office U.S. Nuclear Regulatory Commission RR#1 Steedman, Missouri 65077 Tom Alexion (2)
Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Mail Stop 316 7920 Norfolk Avenue Bethesda, MD 20014 Manager, Electric Department Missouri Public Service Commission P.O. Box 360 Jefferson City, MO 65102
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