ML031080065

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PNPS Table 3.2.A, Instrumentation That Initiates Primary Containment Isolation
ML031080065
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Site: Pilgrim
Issue date: 04/17/2003
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TAC MB3613
Download: ML031080065 (9)
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PNPS TABLE 3.2.A INSTRUMENTATION THAT INITIATES PRIMARY CONTAINMENT ISOLATION Minimum # of Operable Instrument Channels Per Trip System (1) Instrument Trip Level Setting Action (2) 2(7) Reactor Low Water Level 2 11.6" indicated level (3) A and D 1 Reactor High Pressure 5 76 psig D 2 Reactor Low-Low Water Level at or above - 46.4 in. indicated A level (4) 2 Reactor High Water Level *55.4" indicated level (5) B 2(7) High Drywell Pressure

  • 175' F B Temperature 2 Turbine Basement Exhaust Duct High Temperature
  • 300% of rated flow C 1 RWCU Back Wash Receiver Tank Room High 5 148 F C Temperature 1 RWCU Heat Exchanger and Pump Rooms High
  • 148 F C Temperature 1 RWCU Line in RHR Valve Room "A"High Temperature *1480 F C 1 RWCU Line Near East CRD Modules High Temperature <1480 F C Amendment No. 31, 42, 86,147,-150,151,154,162,161, 198 314.2-7

PNPS TABLE 3.2.B (Cont)

INSTRUMENTATION THAT INITIATES OR CONTROLS THE CORE AND CONTAINMENT COOLING SYSTEMS Minimum # of Operable Instrument Channels Per Trip System (1) Trip Function Trip Level Setting Remarks 2 Condensate Storage Tank Low Level > 18" above tank zero Provides interlock to HPCI pump suction valves.

2 Suppression Chamber High Level < 1'11 " below torus zero 1 RCIC Turbine Steam Line High Flow s 300% of rated steam flow (2) 2 RCIC Turbine Compartment Wall (2) 5 1680 F 2 RCIC Exhaust Duct Torus Cavity S 1480 F (2) 2 RCIC Valve Station Area Wall

  • 1980 F (2) 4 RCIC Steam Line Low Pressure 77> P> 63 psig (2)(5)(6) 1 HPCI Turbine Steam Line High Flow
  • 296% of rated flow (3) 2 HPCI Turbine Compartment Exhaust Duct (3)
  • 168'F 2 HPCI Exhaust Duct Torus Cavity (3)
  • 198 0 F 2 HPCI/RHR Valve Station Area Exhaust Duct (3)

< 1680 F Amendment No. 0,148, 198 3/4.2-16

NOTES FOR TABLE 3.2.B

1. Whenever any CSCS subsystem is required by Section 3.5 to be operable, there shall be two (Note 5) operable trip systems. If the first column cannot be met for one of the trip systems, that system shall be repaired or the reactor shall be placed in the Cold Shutdown Condition within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> after this trip system is made or found to be inoperable.
2. Close isolation valves in RCIC subsystem.
3. Close isolation valves in HPCI subsystem.
4. Instrument set point corresponds to 79.96 inches above top of active fuel.
5. RCIC has only one trip system for these sensors.
6. Does not include static head of 17.5 psi.

Amendment No. 108, 118, 151, 198 3/4.2-1 7

PNPS TABLE 4.2.A MINIMUM TEST AND CALIBRATION FREQUENCY FOR PCIS Instrument Channel (5) Instrument Functional Test Calibration Frequency Instrument Check

1) Reactor High Pressure (1) Once/3 months None
2) Reactor Low-Low Water Level Once/3 months (7) (7) Once/day
3) Reactor High Water Level Once/3 months (7) (7) Once/day
4) Main Steam High Temp. (1) Once/24 months None
5) Main Steam High Flow Once/3 months (7) (7) Once/day
6) Main Steam Low Pressure Once/3 months (7) (7) Once/day
7) Reactor Water Cleanup System (RWCU) (1) Once/3 months Once/day High Flow
8) RWCU Back Wash Receiver Tank (1) Once/24 months None Room High Temperature
9) RWCU Heat Exchanger and Pump (1) Once/24 months None Rooms High Temperature
10) RWCU Line in RHR Valve Room "A" (1) Once/24 months None High Temperature
11) RWCU Line Near East CRD Modules (1) Once/24 months None High Temperature Logic System Functional Test (4)(6) Frequency
1) Main Steam Line Isolation Vvs. Once/Operating Cycle Main Steam Line Drain Vvs.

Reactor Water Sample Vvs.

2) RHR - Isolation Vv. Control Once/Operating Cycle Shutdown Cooling Vvs.

Head Spray Discharge to Radwaste

3) Reactor Water Cleanup Isolation Once/Operating Cycle
4) Drywell Isolation Vvs. Once/Operating Cycle TIP Withdrawal Atmospheric Control Vvs.

Sump Drain Valves

5) Standby Gas Treatment System Once/Operating Cycle Reactor Building Isolation Amendment No. 90, 107,130, 151, 198 3/4.2-31

PNPS TABLE 4.2.B MINIIMUM TEST AND CALIBRATION FREQUENCY FOR CSCS Instrument Channel Instrument Functional Test Calibration Frequency Instrument Check

1) Reactor Water Level (1) (7) (7) Once/day
2) Drywell Pressure (1) (7) (7) Once/day
3) Reactor Pressure (1) (7) (7) Once/day
4) Auto Sequencing Timers NA Once/Operating Cyc ale None
5) ADS - LPCI or CS Pump Disch.

Pressure Interlock (1) Once/3 months None

6) Start-up Transf. (41 60V) a) Loss of Voltage Relays Monthly Once/Operating Cycle None b) Degraded Voltage Relays Monthly Once/Operating Cycle None
7) Trip System Bus Power Monitors Once/Operating Cycle NA Once/day
8) Recirculation System d/p (1) Once/3 months Once/day
9) Core Spray Sparger d/p NA Once/18 months Once/day
10) Steam Line High Flow (HPCI & RCIC) (1) Once/3 months None
11) Steam Line High Temp. (HPCI & RCIC) (1) Once/24 months None
12) Safeguards Area High Temp. (1) Once/24 months None Amendment No. 142, 61, 90, 118, 151, 198 314.2-32

PNPS TABLE 4.2.B (Cont)

MINIMUM TEST AND CALIBRATION FREQUENCY FOR CSCS Instrument Channel Instrument Functional Test Calibration FrequencV Instrument Check

13) RCIC Steam Line Low Pressure (1) Once/12 months None
14) HPCI Suction Tank Levels (1) Once/3 months None
15) Emergency 4160V Buses AS & A6 Monthly Once/Operating Cycle None Loss of Voltage Relays Amendment No. 42, 61, 9X, 148, 161, 198 314.2-33

NOTES FOR TABLES 4.2.A THROUGH 4.2.G

1. Initially once per month until exposure hours (M as defined on Figure 4.2-1) is 2.0 x 105; thereafter, according to Figure 4.2-1 with an interval not less than one month nor more than three months.
2. Functional tests, calibrations and instrument checks are not required when these instruments are not required to be operable or are tripped. Functional tests shall be performed before each startup with a required frequency not to exceed once per week. Calibrations of IRMs and SRMs shall be performed during each startup or during controlled shutdowns with a required frequency not to exceed once per week. Instrument checks shall be performed at least once per day during those periods when the instruments are required to be operable.
3. Deleted.
4. Simulated automatic actuation shall be performed once each operating cycle. Where possible, all logic system functional tests will be performed using the test jacks.
5. Reactor low water level and high drywell pressure are not included on Table 4.2.A since they are tested on Tables 4.1.1 and 4.1.2.
6. The logic system functional tests shall include a calibration of time delay relays and timers necessary for proper functioning of the trip systems.
7. Calibration of analog trip units will be performed concurrent with functional testing. The functional test will consist of injecting a simulated electrical signal into the measurement channel. Calibration of associated analog transmitters will be performed each refueling outage.

Amendment No. 12,99,110, 117, 151,-196, 198 3/4.2-41

BASES:

3.2 PROTECTIVE INSTRUMENTATION (Cont) up to the complete circumferential break of a 28-inch recirculation line and with the trip setting given above, CSCS initiation, and primary system isolation are initiated in time to meet the above criteria.

The high drywell pressure instrumentation is a diverse signal to the water level instrumentation and in addition to initiating CSCS, it causes isolation of Group 2 isolation valves. For the breaks discussed above, this instrumentation will initiate CSCS operation at about the same time as the low low water level instrumentation; thus the results given above are applicable here also. The low low water level instrumentation initiates protection for the full spectrum of loss-of-coolant accidents and causes isolation of Group 1 isolation valves.

Venturis are provided in the main steam lines as a means of measuring steam flow and also limiting the loss of mass inventory from the vessel during a steam line break accident. The primary function of the instrumentation is to detect a break in the main steam line. For the worst case accident, main steam line break outside the drywell, steam flow trip setting in conjunction with the flow limiters and main steam line valve closure, limits the mass inventory loss such that fuel is not uncovered, fuel temperatures remain approximately 1000OF and release of radioactivity to the environs is well below 10CFR1 00 guidelines.

Temperature monitoring instrumentation is provided in the main steam line tunnel and the turbine basement to detect leaks in these areas. Trips are provided on this instrumentation and when exceeded, cause closure of isolation valves. The setting of 1750 F for the main steam line tunnel detector is low enough to detect leaks on the order of 2 20 gpm; thus, it is capable of covering the entire spectrum of breaks. For large breaks, the high steam flow instrumentation is a backup to the temperature instrumentation.

Pressure instrumentation is provided to close the main steam isolation valves in the RUN mode before the reactor pressure drops below 785 psig. This function is primarily intended to prevent excessive vessel depressurization in the event of a malfunction of the nuclear system pressure regulator. This function also provides automatic protection of the low-pressure core-thermal-power safety limit (25% of rated core thermal power for reactor pressure < 785 psig). In the Refuel or Startup Mode, the inventory loss associated with such a malfunction would be limited by closure of the Main Steam Isolation Valves due to either high or low reactor water level; no fuel would be uncovered. This function is not required to satisfy any safety design bases.

Amendment No. 34, 113, 151, 154, 198 B3/4.2-2

BASES:

3.2 PROTECTIVE INSTRUMENTATION (Cont)

The HPCI high flow and temperature instrumentation is provided to detect a break in the HPCI steam piping. Tripping of this instrumentation results in actuation of HPCI isolation valves.

Tripping logic for the high flow is a 1 out of 2 logic, and all sensors are required to be operable.

Temperature is monitored at three (3) locations with four (4) temperature sensors at each location. Two (2) sensors at each location are powered by "A" direct current control bus and two (2) by "B" direct current control bus. Each pair of sensors, e.g., "A"or "B", at each location is physically separated and the tripping of either "A"or "B" bus sensor will actuate HPCI isolation valves.

The trip settings of < 296% of design flow for high flow and < 1980 F or < 1680 F. depending on sensor location, for high temperature are such that core uncovery is prevented and fission product release is within limits.

The RCIC high flow and temperature instrumentation is arranged the same as that for the HPCI.

The trip setting of < 300% for high flow and, depending on sensor location, < 1980 F, < 1680 F, or < 1480 F for temperature are based on the same criteria as the HPCI.

The Reactor Water Cleanup System high flow and temperature instrumentation is arranged with one instrument in each trip system for each area. The trip settings are such that core uncovery is prevented and fission product release is within limits.

The instrumentation which initiates CSCS action is arranged in a dual bus system. As for other vital instrumentation arranged in this fashion, the Specification preserves the effectiveness of the system even during periods when maintenance or testing is being performed. An exception to this is when logic functional testing is being performed.

The control rod block functions are provided to prevent excessive control rod withdrawal. The trip logic for this function is 1 out of n: e.g., any trip on one of two RBM's will result in a rod block.

The minimum instrument channel requirements assure sufficient instrumentation to assure the single failure criteria is met. The minimum instrument channel requirements for the RBM may be reduced by one for not longer than 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> without significantly increasing the risk of an inadvertent control rod withdrawal.

Amendment No.440,150,454, 198 133/4.2-3

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