ML20207C692

Proposed Tech Specs Bases,Reflecting Removal of SI Signal on Low Steamline Pressure on Page B 3.3.2-16 & Adding Clarification for Increasing Hydrogen Recombiner Power During Testing on Page B 3.6.7-4

ML20207C692
Person / Time
Site:	Mcguire, McGuire
Issue date:	02/22/1999
From:	DUKE POWER CO.
To:
Shared Package
ML20207C688	List: ML20207C685 ML20207C692
References
NUDOCS 9903090079
Download: ML20207C692 (2)

Text

1

/- ESFAS Instrum:ntition I o B 3.3.2 l 1

BASES l

l 1

APPLICABLE SAFETY ANALYSES, LCO, and APPLICABILITY (continued) l l

Manual and automatic initiation of steam line isolation must be l OPERABLE in MODES 1,2, and 3 when there is sufficient energy in the RCS and SGs to have an SLB or other accident. This could result in the release of significant quantities of energy and cause a cooldown of the primary system. The Steam Line isolation Function is required in MODES 2 and 3 unless all MSIVs are closed and de-activated. In MODES 4,5, and 6, there is insufficient energy in the RCS and SGs to experience an SLB or other accident releasing significant quantities of energy.

c. Steam Line isolation-Containment Pressure-Hiah Hiah s

This Function actuates closure of the MSIVs in the event of a '

LOCA or an SLB inside containment to maintain three unfaulted SGs as a heat sink for the reactor, and to limit the l mass and energy release to containment. The Containment

{

Pressure - High High function is described in ESFAS  ;

Function 2.C. '

Containment Pressure-High High must be OPERABLE in MODES 1,2, and 3, when there is sufficient energy in the l primary and secondary side to pressurize the containment following a pipe break. This would cause a significant increase in the containment pressure, thus allowing detection i and closure of the MSIVs. The Steam Line isolation Function remains OPERABLE in MODES 2 and 3 unless all MSIVs are closed and de-activated. in MODES 4,5, and 6, there is not enough energy in the primary and secondary sides to pressurize the containment to the Containment Pressure-High High setpoint.

d. Steam Line Isolation-Steam Line Pressure (1) Steam Line Pressure-Low Steam Line Pressure-Low provides closure of the MSIVs in the event of an SLB to maintain three unfaulted SGs as a heat sink for the reactor, and to limit the mass and energy release to containment.

This Function provides closure of the MSIVs in the event of a feed line break to ensure a supply of steam for the turbine driven AFW pump:

McGuire Units 1 and 2 B 3.3.2-16 Revision No. 2 9903090079 990222 PDR ADOCK 05000369 p PDR _

o ,/ , Hydrog:n Recombiners c' B 3.6.7 BASES

. SURVEILLANCE SR 3.6.7.1 REQUIREMENTS Performance of a system functional test for each hydrogen recombiner ensures the recombiners are operational and can attain and sustain the temperature necessary for hydrogen recombination. In particular, this SR verifies that the minimum heater sheath temperature increases to 2 700*F in s 90 minutes. After reaching 700 F, the power is increased to maximum power (not to exceed maximum rated power) for approximately l 2 minutes and power is verified to be 2 60 kW.

Industry operating experience has shown that these components usually pass the Surveillance when performed at the 18 month Frequency.

Therefore, the Frequency was concluded to be acceptable from a reliability standpoint.

SR 3.6.7.2 This SR ensures there are no physical problems that could affect recombiner operation. Since the recombiners are mechanically passive, they are not subject to mechanical failure. The only credible failure involves loose wiring or structural connections, deposits of foreign materials, etc.

A visual inspection is sufficient to determine abnormal conditions that could cause such failures. The 18 month Frequency for this SR was developed considering the incidence of hydrogen recombiners failing the SR in the past is low.

SR 3.6.7.3 This SR requires performance of a resistance to ground test for each heater phase to ensure that there are no detectable grounds in any heater phase. This SR should be performed following SR 3.6.7.1. This is accomplished by verifying that the resistance to ground for any heater phase is 210,000 ohms.

The 18 month Frequency for this Surveillance was developed considering the incidence of hydrogen recombiners failing the SR in the past is low.

l McGuire Units 1 and 2 B 3.6.7-4 Revision No. 3