3902 (6/3/14 - 6/6/14) Flashcards

Question

Describe the Normal Flowpath for the Unit 1 Stator Cooling Water System.

Answer 1

1. The two stator cooling water pumps take suction from the stator cooling water storage tank. 2. Water flows from the pump discharge into the two-pass stator water coolers. 3. After leaving the coolers, the water passes through a pressure regulating valve, through one of the two filters, and through a double-basket strainer. 4. The water then flows through the generator.

Answer 2

1. Provide the necessary height of water above the pump suction to ensure Net Positive Suction Head requirements are met. 2. Accommodate surges in system volume. 3. Provide a means of venting H2 that becomes entrained in the system.

Answer 3

725 gpm @ 140 psig.

Answer 4

In-Service pump discharge pressure @ 120 psig decreasing.

Answer 5

* Preferred: Demin Water * Backup: Condensate

Answer 6

Cold gas temp - should be 3-5 ℃ colder than Stator Water Inlet to prevent condensation from moisture in gas from occurring along outside of Teflon tubes - conductor.

Answer 7

1. Low Pressure (2 of 3 Pressure Switches @ 13 psig lowering) 2. Low Flow (2 of 3 Flow Switches @ 195 gpm lowering) 3. High Temperature (2 of 3 Temp Switches @ 95 ℃ for 15 sec) 4. If conductivity reaches 18 µmhos, then the Main Turbine must be tripped manually. * A Generator Trip will occur 30 sec after a Turbine Trip to prevent steam from overspeeding the Main Turbine.

Answer 8

1. To remove heat produced by electrical losses in the generator stator and rotor field windings 2. Safely fill the generator casing with hydrogen. 3. Continually measure the purity of hydrogen while operating. 4. Maintain hydrogen pressure in the generator. 5. Safely remove hydrogen from the generator casing.

Answer 9

1. Its low density (minimal windage losses.) 2. It’s high thermal conductivity.

Answer 10

The purpose of the bulk hydrogen storage is to store the hydrogen used for system fill and makeup of the Main Generator.

Answer 11

* A control cabinet north of the storage tanks contains the regulators, valves, and associated pressure gauges. * Dual pressure regulators reduce the pressure of the gas to approximately 90 PSIG on the supply lines. * A relief valve set at 200 PSIG provides protection for the low-pressure header.

Answer 12

* Automatically closes @ 50 psig lowering. * Protects H₂ inventory & minimizes the possibility of an explosive Turbine Building atmosphere in case of a line break. * Hold the reset button until pressure builds back to \>50 psig to enable reopening.

Answer 13

* 6, 200 SCF H₂ bottles @ 2000 psig. * Located on 591' level. * Used if bulk supply is not available or if accurate hydrogen usage rates are to be determined. * Two pressure regulators in parallel. * Relief valve just downstream of the manifold set at 110 psig. * Relieves to atmosphere thru a line to the roof. * Line to roof is "shared" with other H₂ reliefs and vents.

Answer 14

* Machine Gas Regulator set for~ 60 psigis normally aligned for service but can be bypassed. * Use bypass if regulator has failed.

Answer 15

* Allows CO₂ to be supplied to generator or vented to atmosphere. * Normally positioned for CO2 supply.

Answer 16

Less mixing during purges (H₂ rise, CO₂ is heavy, etc.)

Answer 17

* Provides sufficient volume to perform Normal/Emergency Main Generator Degas. * Normal/Emergency Degas requires 15-20% of Tank Level.

Answer 18

* Provide CO₂ gas supply. * Heat liquid CO₂ using aux. steam. * Design capacity 4000 lb/hr of CO₂.

Answer 19

* The function of the seal oil system is to provide a seal on the generator shaft to contain the pressurized hydrogen within the generator casing. * This minimizes the amount of hydrogen makeup and prevents explosive concentrations of hydrogen from developing around the main generator.

Answer 20

3-8 psig higher than the machine gas pressure.

Answer 21

1. Main Seal Oil Pump (Normal) 2. Emergency Seal Oil Pump (Auto starts @ 125 psig of the MSOP) 3. 120 psig supply from the Main Turbine Shaft Driven L/O Pump (Main Turbine must be \> 1300 rpm) 4. 25 psig supply from the Bearing Oil Header (Can only maintain Seal Oil Pressure @ 8 psig)

Answer 22

Bearings #9 & #10.

Answer 23

The seal oil tank provides a vacuum atmosphere in which entrained air, water vapor, or any other gases can be removed from the seal oil makeup flow before the oil comes in contact with hydrogen in the generator. The vacuum system eliminates the need for frequent purging and reduces the amount of hydrogen required to make up for system losses.

Answer 24

Loss of pump will allow purity of seal oil to degrade over time. No longer degassing or removing moisture.

Answer 25

NESW via the Main Turbine Lube Oil Tank.

Answer 26

The SOVP maintains pressure in the seal oil tank around 1 inch HgA. Absolute pressure less than or equal to 1 inch HgA results in a generator H2 purity of 97% or better.

Answer 27

High oil level in seal oil tank.

Answer 28

The RSOP continuously circulates the contents of the seal oil tank. By spraying the oil through the vacuum space, the RSOP helps to completely strip the air from the oil before it is used for generator sealing.

Answer 29

* Provides a backup supply of seal oil. * Automatically starts when the main seal oil pump discharge pressure falls to 125 psig. * Relief Valve lifts at the discharge of the pump to maintain 130 psig.

Answer 30

* Maintain seal oil supply 3-8 psig above hydrogen pressure. * Two valves in parallel, one is normally in service. * Alarm actuates at 2.5 psid decreasing pressure.

Answer 31

* Gas Sensing Line – Fail Close * Seal Oil Sensing Line – Fail Open * Diaphragm – Fail Open * Spring – Fail Close

Answer 32

* These full flow cartridge filters, again, filter any particulate material from the oil before flowing to the seal rings. * Two in parallel, 1 normally in service. * Maximum differential pressure of 9 psid seen on 2 press gages per filter.

Answer 33

* Separates the Seal Oil return from the Main Turbine L/O when the MTLO System isn't in service. * The tank is vented to atmosphere with a 6 inch pipe to allow air or hydrogen entrained in the oil to bubble out.

Answer 34

* Allows the Oil on the Gas Side of the Generator to drain and release any entrained H_2. * A vertical partition divides the tank into two compartments which are connected through a loop seal. This prevents the circulation of oil vapor through the seal drain piping because of the differential in the fan pressure between the two ends of the generator.

Answer 35

The float trap ensures that hydrogen does not blow by into the seal oil system.

Answer 36

* A stuck open float trap will allow blow-through. * A stuck shut float trap will bring in a high level alarm for the Seal Drain Enlargement. * Must take manual level control if it is a float problem. * Continuously manned while in manual.

Answer 37

SOVP may burn up if the oil supply is lost from the separator tank.

Answer 38

Penetrations into and out of Containment must be closed or capable of being closed in the event of an irradiated fuel accident. Modes 1-4 this is maintained with the Containment System being Operable. Mode 6, with fuel movement in progress, this is maintained wth STP 41 (Containment Closure Capability).

Answer 39

* Hatch is closed and held in place by four bolts. * One door of each air lock is capable of being closed * Each penetration into/out of Containment is either closed by a manual or automatic isolation valve, blind flange or equivalent, or capable of being closed by an Operable Containment Purge Supply/Exhaust System.

Answer 40

If one or more Containment Penetrations is not in required status fuel movement must be suspended immediately.

Answer 41

Verify the following (in order of preference): 1. The required flanges are in place. 2. All valves are Closed, except as noted. 3. All pipe caps, plugs, locks, or seals are in place. 4. Penetration is pressurized.

Answer 42

1. Obtain SRO-CA's permission prior to. 2. Obtain a Data Sheet 1. 3. Perform/verify lineup to ensure Refueling Integrity is being maintained. 4. Attach new page to the front of the original 5. Check off option on the original page that was changed and get SRO to sign off.

Answer 43

* One circuit verifies level and sends a signal to the annunciator panel and level indication on the Sub-panel. * The other controls level as necessary.

Answer 44

There is a Radar sensor that emits short radar pulses of 1 nano second in length that continuously sends a level measurement.

Answer 45

* Two AC Motor Driven Pumps will replace the Shaft-Driven & the Aux AC L/O Pumps. * They will be sized so that only one pump will be in service while the other in standby. * An accumulator will be included to maintain pressure during swaps.

Answer 46

They will be controled from the DSC HMI for the Main Feed Pumps in the Control Room.

Answer 47

2250 **_PSIA_** @ 571℉ to reduce wearing on the Steam Generator Tubes.

Answer 48

* The CTS Pump start delay time will change from 2 sec to 244 sec. * The CEQ fan start delay time will change from 2 inutes to 5.5 minutes. * This will allow for a slower blowdown rate during an accident so that we can keep the peak cladding temperature at a minimum despite the new higher Normal Operating Temperaures in the RCS.

Answer 49

To the Main Transformer on the high voltage side and out through the low voltage side. The 26Kv is then fed through the bus ducts to the Aux Transformers and stepped down to 4Kv and in to the 4Kv room to feed the PCP bus.

Answer 50

1. 69KV (Derby/Bridgman) → TR-7→AB Breaker. 2. Livingston Road

Answer 51

1. Training Center 2. Office Building (New-New Office Building) 3. Service Building (New Office Building) 4. Includes Power to the Reverse Osmosis Unit 5. Containment Access Building (RPAC) 6. South Security Access / MOF 7. Fire Pump House

Answer 52

1. The Unit Aux Transformer. 2. The Reserve Aux Transformers.

Answer 53

1. Unit and Overall Differential Relays 2. Overload/Overcurrent

Answer 54

1. UAT must be energized to close. 2. Must be in Sync to close.

Answer 55

1. Overload/Overcurrent 2. Transformer Fault (RAT)

Answer 56

1. RAT must be energized to close. 2. Must be in Sync to close.

Answer 57

Unit and Overall Differential Relays (Main Generator Trip, Transformer Fault, etc.)

Answer 58

1. RCP – 6000HP 2. Circ Pump – 2750 HP 3. Hotwell Pump 4. Condensate Booster Pump 5. BMC/CMC (on 1(2)B and 1(2)C only) 6. T-Bus

Answer 59

* If powered from the UAT, at 88% of Nominal voltage, for 99 sec a fast transfer to RAT happens for the associated train. * If Degraded voltage continues for 21 Seconds (After Transfer to RAT) the associated RCP Bus Tie Breakers trip.

Answer 60

If power supplied to the RCP busses from the RAT, at 88% of Nominal voltage, following a time delay of 2 Minutes (9 seconds with SI or lo SG level) the RCP Bus Tie Breakers Trip.

Answer 61

Provide water to the steam generators during: 1. Loss of main feedwater. 2. Unit trip. 3. Feedwater or steamline break. 4. Loss of off-site power. 5. Loss of coolant accident. The Auxiliary Feedwater System also provides water during start-ups and shutdowns when insufficient steam is available for the main feed pumps.

Answer 62

182,000 gallons, which is enough to maintain the unit at hot shutdown for nine hours.

Answer 63

1. CST 2. Opposite Unit's CST through the cross-tie (CRV-51) 3. ESW

Answer 64

* East: 2&3 or Opposite unit's 1&4 * West: 1&4 or Oppsite Unit's 2&3 * Turbine Driven: 1-4 of Own Unit's only

Answer 65

**_EDWA_**: East:T11D/T21D West: T11A/T21A Turbine Driven: Steam from 2&3 SG's, electricity from N-Train Battery/Charger.

Answer 66

**_BALLS:_** 1. **_B_**oth Main Feed Water Pumps tripped. 2. **_A_**MSAC 3. **_L_**o-Lo SG Level (1 out of 4 steam generators). 4. **_L_**oad Shed (**_Blackout Sequence!!!!_**) 5. **_S_**afety Injection

Answer 67

1. Overload. 2. Instantaneous overcurrent. 3. Load shed (from respective bus).

Answer 68

NESW. Valved in at 140℉ to maintain less than 160℉.

Answer 69

**_USA:_** 1. **_U_**nder voltage on Reactor Coolant Pump 4kv buses. 2. **_S_**team generator low-low level 2 out of 4 steam generators. 3. **_A_**MSAC Initiated.

Answer 70

1. Electronic overspeed (108%). 2. Mechanical overspeed (111 %). 3. Manual (local, HSD panel and Control Room).

Answer 71

## Footnote By pushing the connecting rod toward the outboard turbine bearing (Stabbing the Turbine).

Answer 72

* The Shaft driven oil pump supplies oil through cooler to the two turbine bearings. * The TDAFP discharge line upstream of ELO supplies cooling water to the Governor and Oil Cooler, and returns to pump suction.

Answer 73

Initiated by signals that automatically start the MDAFP: 1. Seals in for 45 seconds 2. Steam Generator blow down isolation valves close 3. AFW Test valves close 4. The MDAFP FMO's open 5. The Unit 2 TDAFP steam generator supply valves open, the Unit 1 Valves remain in the throttled position.

Answer 74

* Designed to protect against pump run-out conditions following a Main Steam or Feed Water line break. * Pump discharge valves (FMO's) are throttled closed: 1. Affected MDAFP receives a signal at flow of 575 GPM. 2. Affected TDAFP receives a signal at flow of 975 GPM.

Answer 75

The East NESW Valve Gallery.

Answer 76

That Startup Flash Tank area.

Answer 77

Offsite: 1. Reserve Feed (via RCP Bus) & EP (Affected Unit) 2. Reserve Feed OR EP (Opposite Unit) Onsite: 1. Two EDGs (Affected Unit) 2. Which ever EDG needed to support ESW, depending on if the cross ties are open. Could be one, both or neither (Oppostie Unit).

Answer 78

The Main Generator Lockout Relays simultaneously: 1. Trip feed from the UAT's. 2. Close feed from the RAT's. The RAT's: 1. Automatically adjust voltage to maintain 4kV via the Auto Tap Changer.

Answer 79

**_If initially aligned to the Unit Aux Transformers (UAT's):_** * If 88% of rated voltage is sensed on the **_T11(21)A AND T11(21)D_** for 99 sec a fast transfer to the Reserve Aux Transformers (RAT's) is initiated for all four RCP Buses. If Degraded Voltage is still present for 21 seconds following the transfer to the RAT's the tie breakers from the RCP Buses to the T-Buses trip open. **_If initially aligned to the RAT's:_** After 88% of Nominal Voltage is sensed on the **_T11(21)A AND T11(21)D_** for 2 minutes (9 sec if an SI or Lo-Lo SG Level signal present) all four T-Buses divorce from the RCP Buses. **_Once the T-Buses divorce from the RCP Buses (in either case, whether initially aligned to the UAT's or the RAT's):_** 1. Load Shed Actuated 2. EDG Starts – Reenergizes the bus 3. Loads sequence on

Answer 80

* 55# is the normal operating header pressure * 43# the S/B AC Oil pump starts * 36# Emergency DC Oil pump starts * 4# MFP Trips

Answer 81

**_If voltage lowers to less than 80% of nominal voltage on the T-Buses for 2 sec on 2 of 3 undervoltage relays:_** 1. Load Shed Initiated 2. The EDG's start 3. Once EDG's are up to rated speed & voltage, the loads sequence on.

Answer 82

1. After Undervoltage is sensed on the 69kV EP bus for 150 secs. 2. An Open signal to the MDS. 3. After MDS is open, a start signal is sent to the SDGs. 4. The first SDG to reach speed and voltage closes its breaker onto the dead bus. 5. The remaining SDG auto synchronizes to the bus and closes its output breaker. 6. Then the 12-52-SDGS-4 tie breaker is closed to the EP bus.

Answer 83

1. Report to the Control Room. 2. Receive a review of the applicable radiological and safety hazards. 3. Obtain portable lighting and cutting pliers. 4. Perform operational checks on accessible equipment which started as a result of the event (Assuming no SI): * EDGs * AFW pumps * CCW Pumps * ESW pumps * NESW pumps.

3902 (6/3/14 - 6/6/14) Flashcards

(111 cards)