ML20207C472
| ML20207C472 | |
| Person / Time | |
|---|---|
| Site: | South Texas  |
| Issue date: | 02/24/1999 |
| From: | HOUSTON LIGHTING & POWER CO. |
| To: | |
| Shared Package | |
| ML20207C470 | List: |
| References | |
| NUDOCS 9903090036 | |
| Download: ML20207C472 (1) | |
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' POWER DISTRIBImON LIMITS BASES 3/4.2.5 DNB PARAMETERS (Continued) initial FSAR assumptions and have been analytically demonstrated adequate to maintain a minimum DNBR of greater than or equal to the design limit throughout each analyzed transient. The T,yg value of 598 F and the pressurizer pressure value of 2189 psig are analytical values. The readings from at least three channels will be averaged and then adjusted to account for measurement uncertainties l
before comparing with the required limit. The flow requirement (392,300 gpm) includes a measurement uncertainty of 2.8%.
Technical Specification 3.2.5 provides for an alternate minimum measured Reactor Coolant System flow limit consistent with plugging up to 10% of steam generator tubes and Departure from Nucleate Boiling requirements. When using the alternate minimum flow limit, the Tavg limit is reduced to 595 F for Reactor Coolant System flow no less than 380,500 gpm. Setpoint and constant values for OPAT and OTAT are also revised accordingly when this alternate mode of operation is entered.
l The 12-hour periodic surveillance of these parameters through instrument readout is sufficient to ensure that the parameters are restored within their limits following load changes and other expected transient operation.
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9903090036 990224 PDR ADOCK 05000498-P ppg SOUTH TEXAS - UNITS 1 & 2 B 2-6 Unit 1 - Amendment No. 6h-97 Unit 2 - Amendment No. W,44 3429-98 owmmac.wmscswumour.mm.mwww
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