ML20235T815
| ML20235T815 | |
| Person / Time | |
|---|---|
| Site: | Wolf Creek  |
| Issue date: | 10/05/1987 |
| From: | Bailey J WOLF CREEK NUCLEAR OPERATING CORP. |
| To: | NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM) |
| References | |
| ET-87-0310, ET-87-310, NUDOCS 8710130234 | |
| Download: ML20235T815 (2) | |
Text
1 I
W4$LF CREEK 1
NUCLEAR OPERATING CORPORATION John A. Bailey
.i NEYand T.chnic i s.rvie October 5,1987 ET 87-0310 U.S. Nuclear Regulatory Commission l
. ATTN:
Document Control Desk Washington, D.C.
20555
Subject:
Docket No. 50-482:
Response to Request -for l
Additional Information Concerning AMSAC Generic Design Package',
j
Reference:
- 1). Letter '0G-87-35 date'd 8/3/87 ' from RANewton,-
I WOG,.to JLyons, NRC, WCAP-10858-P-A, Revision 1-l
- 2) Letter OG-87-10 dated 2/26/87 from'RANewton,
'WOG, to JLyons, NRC, WCAP-10858-P-A, Addendum 1
- 3) Letter WM 87-0100 dated 3/20/87 from BDWithers, WCNOC, to NRC
- 4) Letter WM 87-0127 dated 4/16/87 from BDWithers, l
WCN00, to NRC l
l Gentlemen:
{
l This letter is being provided as a result of discussions on October '2,
-1987 with Mr. P. O'Connor of the NRC, Mr. D. Shafer of. Union Electric Company' and Mr. K. Petersen of Wolf Creek Nuclear Operating Corporation'(WCNOC).. WCNOC' was. requested to provide additional information concerning the proposed Anticipated Transient Without Scram ( A'IWS) Mitigation -System Actuation Circuitry ( AMSAC) design specifically. addressing the impact of the recently issued Revision 1 to WCAP-10858-P-A, "AMSAC Generic Design Package".
Revision 1 to WCAP-10858-P-A (Reference 1) revised the AMSAC Generic Design Package to address the following:
1.
Addendum 1 to WCAP-10858-P-A (Reference 2) which provided the basis for the AMSAC C-20 setpoint (405 power) and changed the low feedwater flow setpoint for Option 2 was incorporated in Revision 1.
The former is applicable to WCGS 'as discussed in References-3 and 4,
whereas the. latter is not applicable since we are implementing Option 1 based on steam generator' water level.
2.
A variable time delay was added for Options 2 and 3, described on pages. 4-8, 4-9, 5-9, and 5-10 of WCAP-10858-P-A, Revision -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 system to provide the first trip signal at reduced' power 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.
8710130234 871005 PDR ADOCK 05000482 0
... _,,. I / Budington, KS 66839 / Phone: (316) 364-8831 l}
An Equal opportunity Employer hW/He/ VET l
ET 87-0310 Page 2 October 5,1987 3.
The C-20 permissive signal delay was revised from 120 seconds to 360 seconds.
The WCGS AMSAC design will incorporate thir change which allows AMSAC to remain armed for 360 seconds to allow time to perform its function in the event of a turbine trip.
This change is based on AMSAC signal delays at reduced power levels, as discussed in WCAP-10858-P-A, Revision 1.
Therefore, the only change to the WCGS AMSAC design as a result of the issuance of Revision 1 to WCAP-10858-P-A is the increase in the C-20 time delay.
The C-20 setpoint at 40% of NSSS thermal power was previously included in ou-1esign, as discussed in References 3 and 4 If you have any questions conceraing this submittal, please contact me or Mr. O. L. Maynard of my :taff.
Very truly yours, to John A. Bailey L
Vice Prosident Engineering & Technical Services JAB /jad cc:
P. O'Connor (2)
R. Martin J. Cummins I
i I
4 J