ML20153C402
| ML20153C402 | |
| Person / Time | |
|---|---|
| Site: | Summer  |
| Issue date: | 08/24/1988 |
| From: | Bradham O SOUTH CAROLINA ELECTRIC & GAS CO. |
| To: | Hayes H NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM) |
| Shared Package | |
| ML20153C405 | List: |
| References | |
| NUDOCS 8809010124 | |
| Download: ML20153C402 (2) | |
Text
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South Caolina Electric & Gas Computy Ollie S. Bradham J ki yH 29065 uclear tiore -
l-SCE&G August 24, 1988 Document Control Desk U. S. Nuclear Regulatory Commission Washington, DC 20555 Attention: Mr. J. J. Hayes, Jr.
Subject:
Virgil C. Summer Nuclear Station Proposed Technical Specification Change, "D. C. Sources 3/4.8.2" Gentlemen:
This proposed change is to the Surveillance Requirements fo. D. C. Sources, 3/4.8.2 as shown in Attachment I.
The proposed change is to the average electrolyte temperature as referenced in Surveillance Requirement 4.8.2.1.b.3, and the battery capacity as referenced in Surveillance Requirement 4.8.2.1.e.
During an Emergency Power review, it was identified.by the licensee that the calculation for sizing ESF Batteries 1A & IB used derating factors for aging and temperature more conservative than those identified in the Technical Specification.
The calculations used an aging derating factor of 90% and a temperature derating factor of 94% (65'F) as opposed to 80% aging derating factor and 90% (60'F) temperature derating factor as presently stated in the L
Technical Specification.
j l
In respect to the "Aging Factor," it has been identified that 90% for the capacity of the battery at the end of its useful life was used in the original calculation, dated December 26, 1980, based on a letter from the manufacturer, l
In respect to the "Tem 7erature Derating Factor," a factor of 94% for battery capacity has been used to account for the effect of minimum temperature. As identified in the Final Safety Analysis Report (FSAR), Table 3.11-3, the minimum design temperature for the battery rooms is 65'F.
During normal plant operation, the battery room temperature is controlled by a thermostat which is set to maintain the room temperature at 75'F.
If the control system malfunctions, a bistable controller connected to a temperature element in the room will close the supply damper if the temperature falls below 70*F (the
)
dampers will re-open if the temperature increases).
1 The standard temperature for stating cell capacity is 77'F and temperature correction factors are used to determine the additional battery capacity required at lower temperatures to achieve the same battery performance as if it were 77'F.
Electrolyte temperature is assured to be at a temperature equal to or greater than ambient because of the heating effects of the float A
/
charge.
Thus the minimum room design temperature of 65'F has been used in P
conjunction with vendor supplied curves, for the specific battery in use, to (pgo !
I establish the derating factor of 94%.
8809010124 800824 PDR ADOCK 03000395
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Document Control Desk
' August 24, 1988 Page 2 Attachment II to this letter is SCE&G's "No Significant Hazards Determination." This change has been reviewed and approved by both the Plant Safety Review Committee and the Nuclear Safety Review Committee.
Please find enclosed the applications fee of $150.00 required by 10CFR170.
Very truly yours,
$b'
- 0. S. Bradham RJB/05B:bh Attachments c:
D. A. Nauman/J. G. Connelly, Jr./0. W. Dixon, Jr./T. C. Nichols, Jr.
E. C. Roberts W. A. Williams, Jr.
J. N. Grace J. J. Hayes, Jr.
General Managers C. A. Price /R. M. Campbell, Jr.
R. B. Clary K. E. Nodland J. C. Snelson G. O. Percival R. L. Prevatte J. B. Knotts, Jr.
H. G. Shealy i
File (813.20)
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